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Model - Kine
I wonder if maybe the people who lived in this house travelled to America? If anyone knows the story, chuck me an e-mail or something..
In the 1980s, scientists started discovering a new class of extremely bright sources of X-rays in galaxies. These sources were a surprise, as they were clearly located away from the supermassive black holes found in the center of galaxies. At first, researchers thought that many of these ultraluminous X-ray sources, or ULXs, were black holes containing masses between about a hundred and a hundred thousand times that of the sun. Later work has shown some of them may be stellar-mass black holes, containing up to a few tens of times the mass of the sun.
In 2014, observations with NASA's NuSTAR (Nuclear Spectroscopic Telescope Array) and Chandra X-ray Observatory showed that a few ULXs, which glow with X-ray light equal in luminosity to the total output at all wavelengths of millions of suns, are even less massive objects called neutron stars. These are the burnt-out cores of massive stars that exploded. Neutron stars typically contain only about 1.5 times the mass of the sun. Three such ULXs were identified as neutron stars in the last few years. Scientists discovered regular variations, or "pulsations," in the X-ray emission from ULXs, behavior that is exhibited by neutron stars but not black holes.
Now, researchers using data from NASA's Chandra X-ray Observatory have identified a fourth ULX as being a neutron star, and found new clues about how these objects can shine so brightly. The newly characterized ULX is located in the Whirlpool galaxy, also known as M51. This composite image of the Whirlpool contains X-rays from Chandra (purple) and optical data from the Hubble Space Telescope (red, green, and blue). The ULX is marked with a circle.
Image credit: X-ray: NASA/CXC/Caltech/M. Brightman et al.; Optical: NASA/STScI
VICTORY LINER, INC. 7059
Body: Almazora Tourist Star RE Deluxe
Engine: MAN D2066LOH12
Chassis: MAN R39 18.350 HOCL-CIB (PBMR39xxxxMXC00xx)
Route: Cubao, Quezon City - Baguio City, Benguet
Seating: C29Ft (for more on seating codes pls. check www.britishmodelbuses.com/Glossary.htm)
Date Taken: November 9, 2018
Location: EDSA cor. New York Ave., Brgy. Immaculate Conception, Cubao, Quezon City
:: In Explore: 2019-03-21 ::
52 weeks of 2024/week 51 Chiaroscuro
This is an Italian term which literally means 'light-dark'. In paintings the description refers to clear tonal contrasts which are often used to suggest the volume and modelling of the subjects depicted. Artists who are famed for the use of chiaroscuro include Leonardo da Vinci and Caravaggio.
nationalgallery.org.uk/paintings/glossary/chiaroscuro
354/366
Dictionary (noun).
1. A book containing a selection of the words of a language, usually arranged alphabetically, giving information about their meanings, pronunciations, etymologies, inflected forms, etc., expressed in either the same or another language; lexicon; glossary.
2. A book giving information on particular subjects or on a particular class of words, names, or facts, usually arranged alphabetically.
3. A list of codes, terms, keys, etc., and their meanings, used by a computer program or system.
So... it’s official definitions of word DICTIONARY taken from the Dictionary. Sounds not so nice for well educated ears. But nothing to do... I’m “selling what I bought before”...
Any letter in Western Alphabet is a code hiding some sound, letters and numbers in Kabbalah explain the relationship between an eternal and mysterious Creator and the mortal and finite universe (His creation). Any word is encoded subject or meaning. Letter and word are always abstract, you have to know the key to decode it to visual image, simply speak the language. If you came from different country or using different language... you’re helpless... What to do? Use the pictures. They are always international and go strait to your mind.
My DICTIONARY is pictorial. I’m trying to define abstract meanings using my tools, my images, sometimes widening official definition, sometimes arguing or going opposite. My DICTIONARY of IMAGE is... me, my life, my education, my feelings, my existing in art, my collection of Japanese antiques, my CABINETS OF WONDER with all their curiosities.
When I’m surfing through the endless ocean of words, I’m getting a lot but missing also a lot and I never know what’s more...
The second name of my Dictionary of Image is MY CABINETS OF WONDER. It’s dedicated to CABINETS OF WONDER by great American artist Joseph Cornell (1903-1972) who lived not so far from me, also in Queens, New York, but many years ago. He created here his amazing shadow boxes...
My “shadow boxes” are my digital collages inside TTV screen. All my CABINETS OF WONDER with all my good and evil... all for you.
Much better viewed large View On Black
Explore #437, 08/13/2010
lamb curry mixed with okra, sweet red pepper, mushrooms, onion and kale, alongside wholegrain rice and homemade pickled beetroot, centred with chilli sauce, all sprinkled with chilli pepper and seasoned with salt
lamb curry was cooked in the slowcooker a while ago, boxed for the freezer. this was a portion. when reheating this portion i added lemon juice no water
pickled beetroot i cooked the beetroot until soft, cooled, decanted the water, removed the skin, sliced the beetroot, placed in a glass wire topped jar, covered with pickling vinegar and placed in the fridge to be eaten as and when
pickled vegetables www.sarsons.co.uk/recipes/coloured-pickled-vegetables/
okra www.bbcgoodfood.com/glossary/okra-glossary
how to cook okra www.bbcgoodfood.com/howto/guide/how-cook-okra
chilli sauce www.smh.com.au/goodfood/recipes/tomato-and-chilli-jam-201...
7 days 30 different plant based foods flic.kr/p/2pDzPii
olive oil www.bbc.co.uk/sounds/play/m001y2z6
Michael Mosley discovers that enjoying more olive oil in your daily diet can come with a whole host of surprising benefits, including protecting your brain, improving your memory and reducing chronic inflammation. The Mediterranean diet has been shown to be one of the healthiest in the world, and a major component of this is olive oil. Dr Bill Mullen from the University of Glasgow tells Michael about his recent research, which found that two tablespoons of olive oil a day can significantly reduce biological markers of heart disease. Meanwhile our volunteer Ellen, an avid home cook, reaps the benefits of switching to olive oil.
The secret to making great curry
www.theguardian.com/lifeandstyle/2014/oct/31/how-to-make-...
6 Common Cooking Mistakes While Preparing Chicken Curry
Tips To Make It Perfect
www.ndtv.com/food/6-common-cooking-mistakes-while-prepari...
Varieties of Dahl Curry
food.ndtv.com/lists/10-best-dal-recipes-how-to-cook-it-to...
types of curry
curryculture.co.uk/types-of-curry/
how to thicken curry
lianaskitchen.co.uk/how-to-thicken-curry/
spices & ingredients
curryculture.co.uk/category/spices-ingredients/
How to Cook Spices for Chicken Curry | Indian Food
www.youtube.com/watch?v=FV6Elm3gdRA
tamarind sauce
greatcurryrecipes.net/2018/03/26/tamarind-sauce/
more curry information
lamb bhuna
www.kitchensanctuary.com/lamb-bhuna/
what is a bhuna?
www.seasonedpioneers.com/what-is-a-bhuna/
indian restaurant bhuna curry
glebekitchen.com/indian-restaurant-bhuna-curry/
chicken bhuna curry
searchingforspice.com/chicken-bhuna-curry-indian-takeaway...
dhal curry www.youtube.com/watch?v=X1PLIckQebs
Varieties of Dahl Curry
food.ndtv.com/lists/10-best-dal-recipes-how-to-cook-it-to...
types of curry
curryculture.co.uk/types-of-curry/
how to thicken curry
lianaskitchen.co.uk/how-to-thicken-curry/
ps i'm not recommending any of these cookery adventures. they suit my personal taste. photographing to encourage myself to eat more healthily ...
i've created a new group www.flickr.com/groups/cooking_is_my_hobby/ to gather ideas and encourage myself to continue with healthy eating by learning from others if you're interested in cooking, sometimes or a lot, or enjoy the cooking of others, you're always welcome ...
Anthony Burgess - A Clockwork Orange
Penguin Books 3219, 1985
Cover Artist: David Pelham
Revised edition with 21st chapter. No Nadsat glossary.
Alms houses in Polebarn Road, Trowbridge Wiltshire UK.
'Alms means money given to the poor. Almshouses were built by rich people to provide a home for poor people, usually those who were too old or sick to carry on working. These almshouses on Polebarn Road were built in the Victorian period by local cloth manufacturer Roger Brown in memory of his wife. They are called Lady Brown's Almshouses after her.'
Body: Santarosa Modulo 2016-present
Engine: MAN D2066LOH12
Chassis: MAN R39 18.350 HOCL
Route: Pasay City - Baguio City
Seating: C49F (for more on seating codes pls. check www.britishmodelbuses.com/Glossary.htm)
Date Taken: December 28, 2019
Location: Victory Liner Cubao Terminal, Quezon City
There was a faint breeze and the sun was shining through the branches of this large Rhododendron bush in the Botanic Gardens. Perfect conditions to practice some Macro photography.
Since antiquity, wreaths have symbolized the cycle of life, death, and rebirth. It is fitting then that one of the best places for astronomers to learn more about the stellar lifecycle resembles a giant holiday wreath itself.
The star cluster NGC 602 lies on the outskirts of the Small Magellanic Cloud, which is one of the closest galaxies to the Milky Way, about 200,000 light-years from Earth. The stars in NGC 602 have fewer heavier elements compared to the Sun and most of the rest of the galaxy. Instead, the conditions within NGC 602 mimic those for stars found billions of years ago when the universe was much younger.
This new image combines data from NASA's Chandra X-ray Observatory with a previously released image from the agency's James Webb Space Telescope. The dark ring-like outline of the wreath seen in Webb data (represented as orange, yellow, green, and blue) is made up of dense clouds of filled dust.
Meanwhile, X-rays from Chandra (red) show young, massive stars that are illuminating the wreath, sending high-energy light into interstellar space. These X-rays are powered by winds flowing from the young, massive stars that are sprinkled throughout the cluster. The extended cloud in the Chandra data likely comes from the overlapping X-ray glow of thousands of young, low-mass stars in the cluster.
Credit: X-ray: NASA/CXC; Infrared: ESA/Webb, NASA & CSA, P. Zeilder, E.Sabbi, A. Nota, M. Zamani; Image Processing: NASA/CXC/SAO/L. Frattare and K. Arcand
#NASAMarshall #NASA #astrophysics #NASAChandra #NASA #JWST #NASAWebb #star #starcluster #SmallMagellanicCloud
This twig segment is about 5+ cm. long and 1.5+ cm. in diameter. The little red apothecia (microlichen?) on the lower right end of stick look quite different from main big growth with cilia on its fringes and black dots of cephalodia (pockets of cyanobacteria). This short segment came from a much bigger twig I noticed on the ground when walking on the greenway this morning. iPhone 6+ photo.
Here's a glossary of descriptive terms of lichens:
last week,
i bought june taylor's lemon marmalade at rainbow glossary.
it lemon peel is square cut.
i love it . yum yellows !
Book 1 of 12 Volumes.
Each volume of over 1,2000 uncut pages contains upwards of 50 full-colour photographs.
Coming soon to all good (damp-free) bookstores.
Glossary
Boreen: An idyllic Irish country lane.
Excerpt from www.luminatofestival.com: Acclaimed Brazilian artist Regina Silveira reimagines this year’s Luminato Festival Hub at David Pecaut Square with her installation Glossary, a large-scale play on the word “light.” Best known for her explorations of space through optical illusions and geometric constructions, Glossary touches on Silveira’s interest in light and shadow, and the interaction of images with constructed spaces.
Commissioned specially for Luminato Festival, Glossary incorporates a series of coloured, translucent marquees that form a playful pathway bathing Festivalgoers in countless words for light from dialects and languages from across Canada and around the world. At night, the city is illuminated with lasers, as handwritten words for “light” dance across buildings in the downtown core. Visit the Festival Hub and engage with Glossary as it interacts with the cityscape around David Pecaut Square.
Astronomers have directed NASA's James Webb Space Telescope to examine the outskirts of our Milky Way galaxy. Scientists call this region the Extreme Outer Galaxy due to its location more than 58,000 light-years away from the Galactic Center. (For comparison, Earth is approximately 26,000 light-years from the center.)
A team of scientists used Webb's NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) to image select regions within two molecular clouds known as Digel Clouds 1 and 2. With its high degree of sensitivity and sharp resolution, the Webb data resolved these areas, which are hosts to star clusters undergoing bursts of star formation, in unprecedented detail. Details of this data include components of the clusters such as very young (Class 0) protostars, outflows and jets, and distinctive nebular structures.
Credit: NASA, ESA, CSA, STScI, M. Ressler (JPL)
#NASA #STScI #jwst #jameswebbspacetelescope #NASAGoddard #NASAMarshall #astrophysics #space #galaxy
Bumpy grass mounds by the Craven Way track which connects Dentdale to Ribblehead. Meadow ants create such bumps but they tend to be more separated so these are likely to be thufurs caused by freezing of the soil and the micro-movement of soil over many years.
When he closed his eyes, he could still see her face; her smile still haunted him in the darkness behind lids closed tight against the world.
Her name was Tran. Little girl. She had always come in with the others. The older ones. Walking the long and muddy road into the firebase. Past the barbed wire of the perimeter, the sentries with their M16's. The women had done their washing, erasing the grime from green fatigues, never smiling.
She had smiled though. The child running little errands. Bringing them sweet tea, and carting off their laundry. Coyly begging for sweets. He remembered her smile. Tiny teeth stained brown from chewing Betel nut, dirt on her face, eyes like deep, dark pools. Jet-black hair hanging straight and shining, framing her pretty, round and ruddy cheeks. She had smiled for them, lighting her still-innocent, open, grimy little face. Lighting their dusty, olive-drab world. They guessed her age at around 12, but thinking back on it, she had probably been more like seven or eight. War child.
The humidity dripped fat, languid drops of water from the canvas and palm-frond camouflage coverings of the bunker where they hung out, exhausted from the patrol, just before nightfall. A gentle 'pat' sound into the red mud beside green ammo crates. Then darkness would claim it's inevitable supremacy; darkness into which they deeply feared to venture.
They did not own the night; the night belonged to Charlie. And the night was long.
For countless and uneventful weeks they would walk the jungle paths, hearing the squawk and chatter of birds, the rustle of leaves in the canopy and the crunch and slop of their own footfalls through muddy undergrowth. And the heave of their own nervous breathing as they kept tight in formation, pointman out front, treading as nervously as long-tailed cats in a room full of rocking chairs: "Lima Papa niner-zero, this is Whisky Tango two Actual, sector seven clear, over", and the scratchy-tin radio response from the LT at the forward OP: "Roger WT-2, copy, proceed." Day after goddamn monsoon-drenched day.
At the end of each, they'd return to lounge nervously in the dust back at base, clean weapons and drink shitty coffee or warm beer. If they were lucky to have had it brought in with the weekly Huey dump. The bird was always welcome: in the wake of it's clattering blades it brought letters, chow, ammo, and hope (hope that there was still a world out there). Not the World (that was back home; a million miles away), but just a world more normal than this. Dakto, Da Nang, Hanoi, Saigon. They'd shoot the shit, play their Hendrix tapes and try to 'Relax'. Until the next one: another day, another patrol. Another shit-your-pants fuckin' stroll in the bush. Locked and loaded.
But back at base, before the bloated orange orb of the sun dipped into the humid-haze horizon shimmer, there was always the cheerful little smile that would greet them. The village-child, with the dark pool eyes. And hers was the innocence that remained in this torn, stained land.
LRRP detail. The long range patrol. Dreaded orders. Perhaps a follow-up after an arc-light mission. Such devastation could not possibly leave anything alive? But amazingly, it always did. Days and nights deep in jungle's realm. Dirty fingernails, sweat-salt encrusted webbing, fear-dilated pupils in paint-smeared eyes. Tight bellies never warmed by the C-rations they ate when night fell; no bunker, no base, no refuge but the vigilance of their own loose perimeter sentry duty. They'd alternate watch, a whisper in the ear their awakening, "you're up... 0400... two hours 'till dawn." Quivering, sweating, mosquito tormented nights in which every noise was a nightmare come to kill. After four days, nerves frayed like taught cords, rat-ass-sleep-deprived jumpy with fingers clenched on black triggers slick with perspiration.
On the fifth day, they reached a village. A little palm-frond roof covering one stilted hooch. No bird sounds. No jungle noise at all. All wrong. Tension like a drum-drawn canvas over the nerves of the patrol. The hiss and beat of blood in their veins screaming in their ears.
And as he'd kicked open the door, they saw only the rifle barrel pointing out, the trip-wire on the threshold. Slow motion then, as in a dream, he felt the grenades tumbling past, flung by his squad into the hut. And as the sarge tore him to one side, out of the blast radius, just before the white-hot flash of noise and flame torched the inside of the hooch and it's occupants, roaring it's death destruction, he saw one more thing.
He saw a small, round face, jet black hair framing eyes like dark pools, a little grime-stained face, and pretty grin. Looking at him.
Years after, when he closed his eyes, he could still see her face; her smile still haunted him in the darkness behind lids closed tight against the world.
"Blue, blue windows behind the stars,
yellow moon on the rise.
Big birds flying across the sky,
thowing shadows on our eyes.
Leave us
helpless, helpless, helpless..."
- Crosby, Stills, Nash and Young - 1970.
A team of astronomers has used NASA's James Webb Space Telescope to survey the starburst galaxy Messier 82 (M82). Located 12 million light-years away in the constellation Ursa Major, this galaxy is relatively compact in size but hosts a frenzy of star formation activity. For comparison, M82 is sprouting new stars 10 times faster than the Milky Way galaxy.
Led by Alberto Bolatto at the University of Maryland, College Park, the team directed Webb's NIRCam (Near-Infrared Camera) instrument toward the starburst galaxy's center, attaining a closer look at the physical conditions that foster the formation of new stars.
Credit: NASA, ESA, CSA, STScI, A. Bolatto (University of Maryland)
#NASA #STScI #jwst #jameswebbspacetelescope #NASAGoddard #NASAMarshall #astrophysics #space #galaxy
Some of you may not know just how hard it really is to be an "INFLUENCER" . When you're making "CONTENT" for your "FOLLOWERS" you have to be willing to put personal safety aside for the shot. Personally I appreciate their dedication to duty and loyalty to their sheeple!
If you should recognize these folks please let them know I'm open to having a "COLLAB" with them even though I think they're self absorbed narcissistic twits! 😄
Rosa “INGRID WEIBULL” al roserar del Parc de Cervantes, Barcelona.
Rosa “INGRID WEIBULL” en la rosaleda del Parque de Cervantes, Barcelona .
QUOTATION:
Medium red Floribunda.
Registration name: TANweieke
Exhibition name: Showbiz
Bred by Mathias Tantau, Jr. (1912 - 2006) (Germany, 1980).
Floribunda.
Red. Mild, sweet fragrance. 28 to 30 petals. Average diameter 3". Medium, very double, in large clusters, flat bloom form. Blooms in flushes throughout the season.
Short, well-branched. Large, dense, leathery foliage. 5 leaflets.
Height of 16" to 2' (40 to 60 cm).
USDA zone 6b and warmer. Spring Pruning: Remove old canes and dead or diseased wood and cut back canes that cross. In warmer climates, cut back the remaining canes by about one-third. In colder areas, you'll probably find you'll have to prune a little more than that. Requires spring freeze protection (see glossary - Spring freeze protection) . Can be grown in the ground or in a container (container requires winter protection).
SOURCE: www.helpmefind.com/rose/pl.php?n=11154
See/Veure/Ver:
Well of Shiuan - book 2 of the Morgaine cycle - C.J. Cherryh [fantasy novel - November 12, 2015 - 0656]
The Morgaine book series by C.J. Cherryh consist of four novels. The second book "Well of Ivrel"(1976) is commented upon in this report.
The following is my synopsis of the back-story for these four novels:
The ancient Qhal Empire expanded and dominated civilizations throughout the Galaxy. The Qhal are human in appearance and can breed, if desired, with other humanoid beings. The teleportation Gates technology the Qhal reversed engineered and utilized for interstellar travel were discovered in ruins on a dead world. The Qhal did not invent the Gates. Using the Gates the ruthless Qhal who despised other "native" beings imposed their wills without remorse. In the end the downfall of the Qhal was in the nature of the Gates. The Gates in addition to providing instantaneous travel between star systems could also be used to travel forward in time. It is speculated from analysis of ancient Qhal artifacts on many worlds that travel back in time unraveled the Qhal civilization. Qujalin are human offspring that have bred with Qhal beings. Morgaine is a Qujalin who has undertaken a quest to go from world to world destroying the master Gates since there influence corrupts societies, nature and individuals. It should be noted that all worlds contain many Gates but only one Master Gate. Shutting down the Master renders them all just dead stone monuments.
I have not been able to definitely determine the motivation that propels Morgaine to go from world to world closing the Gates. Certainly the Gates are inherently evil but I was she given a mandate by some council or organization or is she self - motivated, the latter appears to be the case as best I can determine. Her journeys are difficult and dangerous yet her persistence and dedication never waivers. There is enormous opposition to her task since those in power lose all when the Gates is sealed. Fortunately she is in possession of an incredibly magical sword - Changling by name - that is partnered with the mystical evil of the Gates and provides her a weapon that can irrevocably draws individuals to oblivion. How she aquired this incredibly powerful weapon is unknown. Use of the sword takes a psychic toll on her. All the books take place in medieval type world. The technologies evident are body armor and cross bows; horses are the only means of transportation. These pre industrial revolution locals makes for interesting stories but I question if the Qhal who were interstellar travelers what happened to their technology?
Vanye the bastard son of Nhi Rijan killed his half-brother Nhi Kandrys and cut off several fingers of his other half-brother Nhi Erij in a fight he was goaded into by the half-brothers. His father was incensed with grief and anger and cursed his son and pronounced him an "ilin" an outcast. Vanye was "claimed" by the Qujalin Morgaine to assist her in defeating a clan leader who aspires for the forbidden knowledge of the Gates. At the story unfolds her becomes her assistant is riding worlds of Master Gates.
Well of Shiuan - book 2 of the Morgaine cycle:
The setting for this book is alien planet that had in the distant past been an outpost of the Qhal. The planet has earth-like conditions and is populated with men and descendants of the Qhal who have breed with the humans. The planet's moon had experienced a cataclysmic event that results in a steadily rising sea level and a forbidding sense of dread among the inhabitants. The society is pre-industrial and feudal ruled by clans who maintain uneasy alliances and truces with adjoining clans. Warriors are respected for their skills with bows and swords and their horsemanship. Anything to do with the Qhal - the Gates or beings with Qhal blood - Qujalin - is an object of justified superstitious dread. Nonetheless some individual's lust for the powers Qhal items can provide. Morgaine and her sworn assistant Vanyn appear intent on closing the Master Gate. Degenerate Qhal, a being masquerading as Vanye's cousin and angry locals conspire to thwart their plan.
This book screams for a glossary of terms - alas there isn't one. The author with a masters of arts in mythology fills her books with cryptic terms for places and locations that, frankly, were unfamiliar to this reader. Alas I had to slow down take a few notes and use some page index tabs to refer back too and I was ok and good to go. It was worth the effort - this is a many-layered story with several very strong personalities competing for the reader attention. The climax of this story, a stand-alone book as published, begs for sequel. Fortunately for us there was one.
I have read several of Ms. Cherryh's books and to be honest they are an acquired taste and put demands on the reader not accustomed to her writing style and narrative pacing. In this book the narrative pacing proceeded glacially. Nonetheless I enjoyed this book and will eventually read the two remaining sequels.
A layout from the 1946 CBS/Hastings House publication on radio terminology. These sketches are sadly lacking any information on artist or designer, which is a shame. I like "Make Local" - and "give the network cue" - "This is CBS..."
Done for Macro Mondays 'Games' theme.
Glossary:
Chanukah: Feast of Lights in Judaism, usually in December.
Dreidel: A 4-sided top for spinning and game playing, usually on Chanukah.
Gelt: Money, originally in coins, given to the kids on Chanukah.
The 4 Hebrew letters on the dreidel's sides stand for: Nes Gadol Haya Poh. A great miracle happened here [in the Holy Land].
The letters you see in the image, direct the person spinning the dreidel on how much to take from the central 'pot' or kitty, how much to put in, or just to pass. For more dreidel folklore, see link:
Nikon D5100, AF-S Nikkor 50/1.8g. The items in the image are about twice life size.
Note: The dreidel resting on the coins in the image was included for illustrative clarity,
and because it looks good ;-)
Another nod to RuPaul's glossary. No glamour, cosplay or flamboyance...just going for natural feminine realness. I like this one because I look so relaxed and natural.
Lowest profile (H/L 18%) in sample of eighteen.
It is often asserted that interior shell-layers conceal the outer shell so that, internally, “marginal rays are never conspicuous” (Fretter and Graham, 1994), but this does not apply to many shells below 40 mm length, such as this one from a shore in North Yorkshire where the majority have thin inner layers revealing exterior colour rays.
SPECIES DESCRIPTION part A BELOW
SPECIES DESCRIPTION part B 3Pu flic.kr/p/BRHsiR
Key id. features 4Pu flic.kr/p/BG8hhs
OTHER SPECIES ALBUMS www.flickr.com/photos/56388191@N08/collections/
PDF available at www.researchgate.net/profile/Ian_Smith19/research
Terms in text used with restricted or specialised meaning are marked with hashtag#; refer to GLOSSARY below.
Patella_ulyssiponensis Gmelin, 1791.
Current taxonomy: World Register of Marine Species (WoRMS)
www.marinespecies.org/aphia.php?p=taxdetails&id=140684
Synonyms: Patella aspera Lamarck,1819 (widely used by many authors until 1970s but now considered by WoRMS to be separate Macaronesian species P. aspera Röding, 1798); Patella_athletica Bean, 1844; P. depressa auct.
Jeffreys (1865) mistakenly took the rudimentary description of P. depressa by Pennant (1777) to be what is currently (2015) called P. ulyssiponensis. Until 1923, most authors followed Jeffreys in applying the name P. depressa Pennant to the wrong species, and in using the name P. intermedia Jeffreys for what is now recognised as P. depressa Pennant. Examination of Pennant's type specimen by Tomlin (1923) exposed the error and authors started to use the name P. athletica Bean, 1844, for what is now called P.ulyssiponensis but, probably to avoid confusion, many retained use of P. intermedia Jeffreys for the true P. depressa Pennant, despite Pennant's priority, until the 1970s (e.g.Yonge & Thompson, 1976).
Vernacular names: China limpet (English); Brenigen dorfelen (Welsh); Ruwe schaalhoren (Dutch);
Meaning of name: Patella (Latin) = little pan, ulyssiponensis (Latin) = from Lisbon.
Shell Description
Patellid limpets have great geographical variation within and between species; this account refers to British specimens.
Up to 50mm long and 20mm high 1Pu flic.kr/p/BpzHx5 . Strong. Conoid; apex to anterior of centre, base ovoid, widest and sometimes angulated at posterior. Profile usually low (H/L 18-34%, sample of 18) 2Pu flic.kr/p/BG8mKq & 3Pu flic.kr/p/BRHsiR . In profile, anterior and posterior straight 4Pu flic.kr/p/BG8hhs , varying to slightly convex 3Pu flic.kr/p/BRHsiR or slightly concave 5Pu flic.kr/p/AUccwq . When not eroded, often sculpture of single, narrow, pale radiating ribs with varying numbers of intervening weaker ribs 6Pu flic.kr/p/AUicEZ but often obscured by algal growths 7Pu flic.kr/p/AUibCP & 8Pu flic.kr/p/BpznqS . Sometimes ribs project from aperture-rim as points 9Pu flic.kr/p/Bicbta & 10Pu flic.kr/p/BRH5pv , but frequently eroded down 11Pu flic.kr/p/BPsC4f . Dark radiating rays between strong ribs often coalesce into bands 11Pu flic.kr/p/BPsC4f .
Most published descriptions and illustrations are confined to specimens with well-developed, thick, porcellaneous layers on the shell-interior e.g. www.conchsoc.net/spAccount/patella-ulyssiponensis . Some of this form show features defined by differences of orange staining 14 Pu flic.kr/p/BpCkES and/or reflectivity Pu1 flic.kr/p/BpzHx5 resulting from differences in crystal-form of shell-material made by different parts of mantle. Following regions may then be recognised: 1) aperture rim, minute part (or none) of pigmented exterior shell-layer; secreted by mantle-edge, 2) wide peripheral “skirt layer” that reflects light, often iridescing blue, from many short crystalline lines parallel to rim; secreted by mantle-skirt, 3) narrower, matt, opaque, “pallial groove-band”; secreted by mantle roofing groove that contains gills, 4) translucent, horseshoe-shape “pedal-retractor muscle scar”; mark left by muscle attachment, 5) very thin “anterior mantle-attachment scar” connecting ends of pedal-retractor scar; mark left by mantle attachment, 6) central “amphora area” enclosed by scars 4 & 5; secreted by mantle over visceral hump, 7) short mark across pallial groove-band where efferent pallial vessel enters nuchal cavity through gap in pallial gills. On this form, interior layers conceal outer shell so, internally, “marginal rays are never conspicuous” (Fretter and Graham, 1994).
However, on some shores , e.g. in north Yorkshire, majority have thin inner layers revealing exterior colour rays 2Pu flic.kr/p/BG8mKq & 11Pu flic.kr/p/BPsC4f , sometimes across whole shell 16Pu flic.kr/p/BpChy1 (apart from some with length c.40mm and over 12Pu flic.kr/p/AUfeNo ) . On these, the structural features 1-7 described above are usually indiscernible or ill-defined, apart from frequently orange-stained amphora area 13Pu flic.kr/p/BRLd2Z and iridescent lines in skirt-layer 15Pu flic.kr/p/AUm6kt .
Spat, length 1mm, lack ridges on main anteroposterior axis and have broad, prominent, mid-lateral pigment lines running straight (not swept forwards or backwards) from apex to lip.
Body description
Translucent white head, with pink internal odontophore showing through 17Pu flic.kr/p/BJtvfi ; has substantial snout , folds in at posterior, with large mouth (transverse when shut) fringed by thick, yellow, outer lips (whitish when small); inner lips darker yellow, open laterally for protrusion of radula 18Pu flic.kr/p/Bif5cB . Cephalic tentacles similar colour to head and/or mantle-skirt 19Pu flic.kr/p/AUeYf9 & 18Pu flic.kr/p/Bif5cB , with small black eye in slight swelling at base. Eye is primitive (or degenerate) cavity, open to seawater and lined with black retina cells 17Pu flic.kr/p/BJtvfi & 18Pu flic.kr/p/Bif5cB . Mantle skirt translucent, usually darker than body colour; buff-white/cream 5Pu flic.kr/p/AUccwq , buff-grey 20Pu flic.kr/p/AUeX8j , or yellow 21Pu flic.kr/p/AUuNww ; colour most saturated when skirt retracted from shell-periphery 22Pu flic.kr/p/BGqz3N . Skirt contains efferent pallial vessel 23Pu flic.kr/p/BGqwhs . Mantle cavity consists of nuchal cavity over head, and pallial groove filled with pallial gills around entire periphery of foot-head 24Pu flic.kr/p/BS1DhR ; no ctenidium. Each gill is tongue-shaped leaflet attached by stalk to distal wall of pallial-groove and has densely ciliated groove on stalk and thickened rim 25Pu flic.kr/p/BGqt5A (Fretter & Graham, 1994). Mantle-edge has many white, off-white , cream or, on large specimens, yellow or orange pallial tentacles 26Pu flic.kr/p/BGqszN ; basal half opaque becoming translucent and less intensely coloured distally; opaque basal parts distinct from translucent mantle-skirt that they arise from. Length of pallial tentacles alternates around perimeter with two or three short ones between each pair of long ones; length varies with extension 27Pu flic.kr/p/AUuCc3 & 28Pu flic.kr/p/BPGWSQ . Visibility of pallial tentacles, and their position relative to shell, vary with degree of extension of mantle skirt 10Pu flic.kr/p/BRH5pv . Pedal-retractor muscle, a U of white muscle bundles 28Pu flic.kr/p/BPGWSQ demarcated by gaps 24Pu flic.kr/p/BS1DhR , attaches body/foot to shell 22Pu flic.kr/p/BGqz3N . Sole of foot approximately circular with flattened anterior 29Pu flic.kr/p/AUAAHD to broadly elliptical 5Pu flic.kr/p/AUccwq . Colour of sole varies: small whitish ones may have shadow of dark viscera if gonads undeveloped 30Pu flic.kr/p/BGqk4q ; adults, pale-yellow/cream, yellow 31Pu flic.kr/p/BGrKw1 or orange 21Pu flic.kr/p/AUuNww ; sometimes slightly-greenish tinted median zone where foot thinnest if greenish female gonads resting on inner surface of foot. White or yellowish-white 32Pu flic.kr/p/BpU3pC sides of foot lack features such as epipodial tentacles. When crawling, usually only extended pallial tentacles and, perhaps, tips of cephalic tentacles protrude beyond shelter of shell. No penis as fertilization external.
Further detail visible with simple dissection
Shell removal by severing pedal-retractor muscle shows muscle-bundles clearly 28Pu flic.kr/p/BPGWSQ ; anterior bundle on each side is largest and strongest as must firmly pull down shell further to anterior where bundles are absent. Shell removal exposes entire mantle 33Pu flic.kr/p/BJKhmk subdivided into a) pale translucent mantle-skirt, b) narrow black band over pallial-groove containing gills, c) large black amphora-shaped area, sometimes paler near vertex, over viscera and nuchal cavity containing the head 34Pu flic.kr/p/BGrCQW and d) pale anterior mantle-attachment. Removal of black amphora area of mantle reveals viscera 35Pu flic.kr/p/BivTv4 including heart, digestive gland, intestine and, if in breeding condition, gonads protruding from below. When roof of nuchal cavity removed, translucent white head, usually showing pink of internal odontophore, is visible 35Pu flic.kr/p/BivTv4 , and removal of viscera reveals radula, folded to fit in body 36Pu flic.kr/p/AUvMhW . Removal of head's epithelium reveals odontophore and anterior of radula 37Pu flic.kr/p/BGrzwG . Radula long, relative to shell length, ( R/S 80-140%); shorter on average (but with overlapping range) than those of P. vulgata (113-230%) and P. depressa (140-270%) (Fretter & Graham, 1962, p.172). Fully mineralized, rust-coloured radular teeth, ready for action, clearly visible on hyaline shield at anterior; those further back partly obscured as in white radular sac. At anterior of radula, a white chitinous unarticulated jaw#, and white, cuticularized, triangular licker divided into plate-like ridges by deep transverse grooves 38Pu flic.kr/p/BJKboP . Each row of teeth arranged in docoglossan formula, 3+D+2+R+2+D+3: at centre, two pairs of large, unicuspid, pigmented lateral teeth (with small, unpigmented rachidian/median tooth hidden from easy view at their base), and near each margin of ribbon a single, tricuspid, pigmented, dominant-marginal tooth with, close-by, three inconspicuous, unicuspid, marginal teeth. Before and during summer breeding season, large gonads occur in mature adults between viscera and foot; female ovaries granular and yellow to green; male testes pink/orange with numerous interconnected tubules 39Pu flic.kr/p/BGrxio .When fully developed, gonads spread up around periphery of visceral mass 35Pu flic.kr/p/BivTv4 .
SPECIES DESCRIPTION part B at 3Pu flic.kr/p/BRHsiR
GLOSSARY
amphora – (on interior of limpet shell) Roman amphora-shaped area enclosed by scars of pedal-retractor muscle and anterior mantle-attachment.
anteroposterior – (of linear feature) aligned from anterior to posterior.
aperture – mouth of gastropod shell; outlet for head and foot.
apex - earliest formed part of a gastropod shell, the summit of the cone. (In this limpet-account restricted to the exterior of the shell, and “vertex” used for the interior.)
auct. - (abbreviation of “auctorum” = “of authors”) name, often of another valid species, used in error for this one by other author(s). en.wikipedia.org/wiki/Auctorum
cephalic – (adj.) of or on the head.
cilia – (pl.) microscopic linear extensions of membrane that move in rhythmic waves to create locomotion, or move particles and liquids e.g. inhalent water currents. (“cilium” singular). (Electron scanning microscope image at flic.kr/p/qQB5zj )
ciliary – (adj.) relating to or involving cilia.
coll. – in the collection of (named person or institution) (compare with legit).
conoid – shaped like a cone.
ctenidium – comb-like molluscan gill; usually an axis with a row of filaments either side.
ELWS – extreme low water spring tide (usually near March and September equinoxes).
epipodial - (adj.) of the epipodium (collar or circlet running round sides of foot of some gastropods).
epithelium – membranous covering of internal and external surfaces of animal's body, e.g. skin and lining of tubes and cavities.
head scar – term used by many British authors for patch of different shell-material, and often different colour, near vertex of interior of limpet shell; misnomer as the mobile head, free of any attachment to the shell or mantle-roof of the nuchal cavity cannot make a scar. A preferable term is “vertex patch”.
height – (of limpet) perpendicular distance from apex to plane of aperture-rim (best measured with callipers).
hyaline shield – transparent sheet of chitin at anterior of radula that rests on bolsters of odontophore; attachment point for retractor muscles of radula; helps guide food particles into mouth.
jaw - unarticulated chitinous structure that encloses inner lips of Patella spp. at sides and anterior.
legit – (abbreviation; leg.) collected/ found by (compare with coll.)
licker - cuticularized structure with plate-like ridges and deep transverse grooves at tip of radula of Patella spp.; retains and sweeps up food particles.
Macaronesia – Madeira, Canary Islands, Cape Verde Islands and Azores.
mantle – sheet of tissue covering visceral mass of molluscs. Secretes shell of shelled species, and forms part or all of dorsal body surface (notum) of those without shells. (See mantle skirt.)
mantle skirt – extension on gastropods of mantle proper as a flap roofing a cavity containing gills, genital and renal openings, anus etc. On limpets, skirt and cavity extend around periphery of animal.
MLWS - mean low water spring tide level (mean level reached by lowest low tides for a few days every fortnight; Laminaria or Coralline zone on rocky coasts).
nuchal – (adj.) of nape of the neck.
nuchal cavity – cavity roofed by mantle skirt that contains head of limpet; part of mantle cavity (remainder consists of pallial groove on each side of body).
ovoid – egg-shaped, (as a solid or in outline).
ovate – egg-shaped, (as a solid or in outline).
pallial groove band – shell material deposited on interior of shell by strip of black mantle roofing the pallial groove that contains the gills. On British Patella spp. it is often clouded-white.
pedal retractor muscle – strong muscle that retracts foot into shell of most gastropods, but on limpets is used to clamp shell to substrate, a.k.a. “foot muscle”.
porcellaneous – resembling vitreous glazed ceramic material.
retrograde - (of locomotion waves on foot) waves travel from anterior to posterior.
scar – mark on shell made by attachment point of muscle or other body part.
skirt shell layer - shell material deposited on interior of shell by mantle skirt. On British Patella spp. colourless when deposited, and clouded white, or transparent showing the colours of the outer layer. Crystalline structure causes short lines of blue iridescence parallel to the aperture rim on all four British species of Patella when the light is right.
tricuspid - (of tooth) having three points.
trochophore – spherical or pear-shaped larva that swims with aid of girdle of cilia. Stage preceding veliger, passed within gastropod egg in most spp. but free in plankton for patellid limpets, most Trochidae and Tricolia pullus.
unicuspid - (of tooth) having a single point.
veliger – shelled larva of marine gastropod or bivalve mollusc which swims by beating cilia of a velum (bilobed flap).
vertex – angle at highest point on interior of limpet-shell. [Synonym of “apex”, chosen (by IFS) to help avoid confusion with the highest point, apex, on the exterior. In classical Latin “vertex” was used for the “pole of the heavens”, obviously only seen from below.]
vertex patch –layer of different shell-material, and often different colour, at vertex of interior of limpet shell. (See “head scar”.)
Ed Benguiat (1927–2020, RIP) tossed together a spread in Ed Rondthaler’s 1981 book, “Life With Letters”, that arguably remains the best type anatomy diagram ever. One could quibble about a few omissions and the odd definition for “tittle” (maybe one of his jokes), but it’s damn near perfect. I should have just put this at the front of my book and been done with it.
Littorina fabalis male. A large obvious penis, positioned at the posterior of the head on the right side, is present on mature males in all seasons, and can be exposed on dead or living specimens of both species.
Shell height 12.5mm. Llŷn, North Wales. September 2015.
FULL ACCOUNT BELOW
Sets of OTHER SPECIES:
www.flickr.com/photos/56388191@N08/collections/
PDF available at www.researchgate.net/publication/351037569_Differentiatin... .
Differentiating Littorina obtusata sensu stricto (Linnaeus, 1758)
from Littorina fabalis (Turton, 1825).
Ian F. Smith
Abstract
Adult males of Littorina obtusata sensu stricto and L. fabalis (synonym L. mariae) can be reliably differentiated by the forms of the penes on both extracted dead specimens and unsedated intact animals. Differentiation can often be made within a local population on the basis of shell form, size and colour after these features have been correlated with penis forms in a sample of specimens. The shell features can then be used to identify further local specimens, but cannot be relied on at other localities without confirming penis forms there.
Materials, methods, protocols for acquiring experience, environmental associations of phenotypes, and some sample sites are described and illustrated.
Contents
1. Preliminary check.
2. Taxonomic history.
3. Identification resources.
4. Penis examination methods.
5. Differences in penis morphology.
6. Differences in female anatomy.
7. Differences in shell morphology and colour.
7a. Shell colours.
7b. Shell sizes.
7c. Shell spires.
7d. Shell apertures.
8. Phenotypes of different wave exposures.
8a. Sheltered shores.
8b. Semi-exposed shores.
8c. More exposed shores.
9. Collecting and reliable recording.
10. Acknowledgements.
11. References and web links.
12. Glossary.
1. Preliminary check
Lacuna pallidula, detailed account below image flic.kr/p/hTnxJa , has a similar low spire, very similar spawn, and occurs with L. fabalis on Fucus serratus . It has a much thinner shell with widely open umbilicus, contrasting with the thick columella of L. fabalis.
2. Taxonomic history of L. obtusata and L. fabalis.
1758 to 1914: multiple species and varieties named.
1915 to 1965: all species, except Arctic varieties with spires, combined into one species referred to as Littorina obtusata (Linnaeus, 1758) or, mainly by British workers, as L. littoralis auct. For detail of historic nomenclature confusion see caption below image 1Dof flic.kr/p/QFCUWm .
1966 to 1988: gradual acceptance of two species, based on penis differences, named L. obtusata sensu stricto (Linnaeus, 1758) and L. fabalis (Turton, 1825), synonym L. mariae Sacchi & Rastelli, 1966. Arctic varieties with pointed spires were included in one or other of the pair on the basis of their penes.
In the following account, any use of “L. obtusata” in the now unaccepted sense of including both species has “sensu lato” or “s.l.” after it. The name with no addition, or sometimes for emphasis with “sensu stricto” or “s.s.”, refers to the now accepted segregated sense.
3. Identification resources
Differentiation of the two species by penis form was first published in 1966 by Sacchi & Rastelli, but did not appear in many identification guides until the late 1980s. Consequently, most pre 1988 works, apart from post 1966 specialist papers, are of limited use. Some later publications, such as Graham (1988), recognise the two species but provide insufficient information and images for discrimination of the many phenotypes. Hayward & Ryland (1990) and Hayward & Ryland (1995 & reprints to 2009), have images www.seawater.no/fauna/mollusca/fabalis.html that confuse www.ispotnature.org/node/646985 as the only L. mariae shell illustrated has features frequent on juveniles of both species, and the L. obtusata image has thick aperture walls more typical of L. fabalis.
Williams (1990) has useful information on forms and ecology. The authoritative volume Systematics and evolution of Littorina by Reid (1996) has fifty A4 pages of detailed description and comparison of all phenotypes and geographical variations of these two species. It is essential reading for those undertaking scientific study of Littorina species www.raysociety.org.uk/publications/zoology/the-systematic... .
4. Penis examination
“...only the characters of the adult reproductive system are unequivocal... . ...identifications using [shell features] should be confirmed by dissection before routine application in the field” (Reid, 1996). A rare ambiguity in penes linked to hybridization has been reported at one site in Portugal (Carvalho et al., 2016). An obvious penis, positioned at the posterior of the head on the right side 2Dof flic.kr/p/RcvnFf , is present on mature males in all seasons, and can be exposed on dead or living specimens.
Dead material
Specimens can be killed instantly by plunging into boiling water, or by leaving in a freezer overnight, or by gradually adding Magnesium chloride or Magnesium sulphate crystals to the water in a small container to first anaesthetize and then kill them. The only dissection required is to carefully crush the shell in a tabletop vice with any rubber protectors removed 3Dof flic.kr/p/QFCUmy , avoiding damage to the soft parts, and to pick off the broken fragmets. This method allows unrestricted view of all the necessary details and is quick and reliable, but requires killing of the specimen and destruction of the shell. Alternatively, if boiled for several minutes, the animal can be extracted with a pin from the unbroken shell. Though the penis as a whole is likely to contract on death, especially if boiled, and will be fixed in one of several possible expansions and positions 4Dof flic.kr/p/QFCUab , its glands are often distended and more easily discerned, and it is likely to resemble published images of dead specimens 4Dof flic.kr/p/QFCUab .
Living unsedated specimens
Penes can be examined and photographed on live specimens without harm or anaesthesia using the techniques described in Smith (2012 & 2016 flic.kr/s/aHskNP6GoL ). While live, the penis can be held in a variety of positions 5aDof flic.kr/p/Q2jb82 & 5bDof flic.kr/p/Rcvmo5 and will often be generally more expanded than on dead material, but the glands are often less prominent than on dissected penes and frequently hidden when held against the body. Time and patience will be required as this pair of species may be reluctant to extend from their shells, and several views or images may be needed to accumulate the necessary detail. Best results are obtained if the examination can be within 48 hours of capture. When not being examined, keep in a refrigerator at about 6°C in tightly closed plastic boxes dampened by, but not awash with, seawater. L. fabalis will extend when immersed and restrained 7Dof flic.kr/p/Q2jabc as described in Smith (2012 & 2016), but L. obtusata s.s. exposes itself more readily when damp than when submerged 8Dof flic.kr/p/RcvkCY & 9Dof flic.kr/p/Q2j9un .
5. Differences in penis morphology,
Mamilliform penial glands
L. fabalis has 3 to 17 large glands in a single row along 40% to 70% of the ventral edge of its penis 10Dof flic.kr/p/Rcvk2Y . The glands are usually visible on live unsedated specimens 7Dof flic.kr/p/Q2jabc .
L. obtusata has 10 to 54 closely packed small glands, in one or more irregular rows along 75% to 90% of the length of its penis 10Dof flic.kr/p/Rcvk2Y near its ventral edge and on the mesial face usually held against the body 9Dof flic.kr/p/Q2j9un ; sometimes multiple rows occupy 60% of the width of the penis. The small glands often do not protrude into view on live unsedated specimens unless the penis is twisted to expose the proximal face 11Dof flic.kr/p/RfXgF8 .
Filament (glandless tip of penis).
L. fabalis has long and vermiform filament. On dead or anaesthetized specimens filament is 30% to over 60% of total length of penis 10Dof flic.kr/p/Rcvk2Y . Growth is allometric; small individuals frequently have filaments 30% to 40%, while the largest usually have filaments of 50% to >60% of penis length 6Dof flic.kr/p/RTWK1i . Penis is motile and varying in length on any individual unsedated specimen 5bDof flic.kr/p/Rcvmo5 , and the appearance is affected by positioning/angle of view, so it is advisable to take several observations or photographs when examining live specimens.
L. obtusata has short triangular filament. On dead or anaesthetized specimens 10% to 25% of total length of penis 10Dof flic.kr/p/Rcvk2Y . On live unsedated specimens it may be difficult to discern the precise limit (distal gland) of the filament because the small glands are hidden. However, being short, wide and triangular, it is obviously different 12Dof flic.kr/p/RfXgop & 13Dof flic.kr/p/RfXg8z from the vermiform filament of L. fabalis.
Size of penis depends on the size of the individual male and is not diagnostic of species. On the sheltered Menai Strait, most adult male L. obtusata are larger, and so have larger penes, than most male L. fabalis. On more exposed shores in North Wales, the sizes of the two species can be almost equal.
6. Difference in female anatomy
The copulatory bursa, requires skilled dissection and cannot be examined without killing. It is not illustrated here, see Reid (1996) for details and diagrams.
L. fabalis; half length of jelly gland, not reaching capsule gland.
L. obtusata; extends full length of jelly gland to capsule gland.
The ovipositor can be observed on live females restrained as described in Smith (2012 & 2016). Goodwin & Fish (1977) stated that, in 99% of cases examined by them in Wales, its colour is “to varying degrees black pigmented” on L. obtusata 14Dof flic.kr/p/RfXfWn , while L. fabalis “lacks pigmentation” 15Dof flic.kr/p/RfXfGp , but this was not my experience in Wales 16Dof flic.kr/p/Q2j6nF , and Reid (1996) also found it not always so . The colour is often lost on preserved specimens as the surface frequently sloughs off.
To identify females without dissection, the shell forms and shore zone of each species on the same shore need to be ascertained by examination of some penes on males. This information can also be used to find if local ovipositor colours conform with Goodwin and Fish (1977).
7. Differences in shell morphology and colour
No single shell feature is diagnostic in all situations, and some features intergrade. When several features are considered in combination with habitat detail, it is often possible to give a probable identification, but, for certainty, confirmation by examination of penes is required. Some shores, such as in Denmark and from Kent to Dorset, have problematic shell forms, so penis examination is especially necessary (Reid, 1996). Correlations, validated by penis examination, of species with shell form and colour on specific shores can be found in published previous studies, but should be used with caution as shell form may vary on different parts of the same shore (Reimchen, 1981) and may change from year to year with variation in the climate. Shells of Arctic and subarctic populations differ from those south of the Lofoten Islands; they are less well known and are excluded from this account except where specifically mentioned; further detail in Reid (1996).
7a. Shell colours of both species are often classified with the terms below; percentages are of specimens in a large collection of a mixture of both species from across Britain (Smith, 1976, in Reid, 1996). Some authors give slightly different interpretations of a colour term for each species, and it can be difficult to define the limits of fusca, brownish olivacea and faintly marked dark reticulata. Colours are best viewed on live specimens in water as the shell and the periostracum, which often contributes to the colour, erode and fade readily on dead shells 17Dof flic.kr/p/R5n3xZ .
Olivacea: 55%. Exterior olive green 18Dof flic.kr/p/RfXeZ2 to olive brown 19Dof flic.kr/p/R5mYDB , interior often purplish to brownish. Usually the commonest colour form, and almost diagnostic, of L. obtusata on shores well sheltered from waves. An algal coating on L. fabalis 20Dof flic.kr/p/R2FMv5 may confuse unless scraped off; true olivacea L. fabalis are extremely rare or absent in Britain, but they do exist in at least two places in Galicia, Spain on Zostera.
Reticulata: 33%. Exterior yellow to brown with darker reticulate 21Dof flic.kr/p/PYwgVE , chequered 22Dof flic.kr/p/R2FKwW or zig zag 23Dof flic.kr/p/Rcvdds pattern; interior varied, can be white 21Dof flic.kr/p/PYwgVE , sometimes tinted pink or violet and sometimes with exterior pattern showing near rim within aperture 24Dof flic.kr/p/R2FJeL . Usually the commonest colour form of both species on shores exposed to wave action.
Citrina: 10%. Exterior yellow 25Dof flic.kr/p/Rcvc5A grading to white; interior white 26Dof flic.kr/p/R3LhL5 . Usually the commonest colour of L. fabalis on shores well sheltered from waves, but not diagnostic as it also occurs on L. obtusata 27Dof flic.kr/p/R3Lhcj on the same shores.
Fusca: dark brown to black on L. obtusata 19Dof fig.5 flic.kr/p/R5mYDB ; dark chestnut brown on L. fabalis (Reid, 1996). Rare, generally less than 1%, but 100% of sample of 14 L. obtusata s.l. from a site on brackish Isefjord, Denmark (Rasmussen, 1973). A sample of 8 thin shelled, dwarf, L. fabalis from exposed cliff near Aberdeen all appear to be form fusca, but the specimens, at 28Dof flic.kr/p/PZBeay , were photographed 45 years after death, so the colour may have altered.
Each of following less than 1%.
Aurantia: orange. 29Dof flic.kr/p/PZBdiU
Rubens: red or brick red. 30Dof flic.kr/p/QGHGD9
Inversicolor: two broad dark bands. 31Dof flic.kr/p/PZBccW
Zonata: single pale band around periphery (“equator”) of bodywhorl. 33Dof flic.kr/p/R6s4Fe (right specimen).
Alternata: two pale bands. 33Dof flic.kr/p/R6s4Fe (left specimen).
On some shores, juvenile L. fabalis up to 4mm diameter are pure white resembling the 3.5mm diameter spiral tubes of spirorbid worms living on the fronds of Fucus serratus frequented by L. fabalis. With later growth of another colour, the juvenile shell is preserved as a pure white early spire 23Dof flic.kr/p/Rcvdds & 34Dof flic.kr/p/QGHFW7 . Care is required as the spire of L. obtusata is often eroded to dingy whitish, though careful examination will often show traces of the eroded colour 35Dof flic.kr/p/Rdzcqb . And populations of L. fabalis lacking white spirorbid like spires can weather to dingy white with traces of colour in the same way as L. obtusata 36Dof flic.kr/p/R6s3wF .
7b. Shell sizes
On most shores, L. obtusata has a larger mean height than L. fabalis, but there is usually a large overlap in sizes of the largest L. fabalis specimens and young specimens of L. obtusata 37Dof flic.kr/p/R3LbTo . The mean size of both species varies greatly with local conditions 44Dof flic.kr/p/Q3o4dM .
7c. Shell spires
In Britain and most of Atlantic Europe, generally, but not consistently enough for reliable differentiation, L. fabalis has a flat or very low spire 36Dof flic.kr/p/R6s3wF and L. obtusata a low 38Dof flic.kr/p/R6s1kr or slightly raised domed spire 18Dof flic.kr/p/RfXeZ2 , often with an angled shoulder on the body whorl giving a squared or barrel like profile 38Dof flic.kr/p/R6s1kr . Juveniles of both species usually have flatter spires than adults 31Dof flic.kr/p/PZBccW , 32Dof flic.kr/p/R6s4KH , 39Dof flic.kr/p/QGHEsW & 50Dof flic.kr/p/R3L2LW .
Occasional specimens 40Dof flic.kr/p/R6s1gD or local populations have a protruding pointed spire, especially in sheltered brackish conditions, e.g. L. obtusata var. aestuarii in the tidal River Deben, Suffolk, in Jeffreys (1869) fig. 8, plate CI at archive.org/stream/britishconcholog05jeffr#page/n489/mode... (now scarce or extinct at that locality). On Arctic and subarctic shores north of the Lofoten Islands, and in Greenland and most of Iceland, many of both species have protruding pointed spires. Only L. obtusata occurs in Atlantic North America; it often has a developed spire in northern Maine and Canada.
7d. Shell apertures
Aperture size is affected by the physical and biological environment, and juveniles have a less expanded body whorl and aperture. The shell walls thicken with maturity in both species, constricting the aperture internally, generally more markedly in L. fabalis, but varying in degree with environment. The most useful measure of shell thickness is that of the lip at the base of the columella (C) divided by the length of the aperture (LA) 41Dof flic.kr/p/R6rZHz . In a sample of 59 adult shells, including less frequent extreme forms, C/LA was usually less than 0.29 on L. obtusata and greater than 0.29 on L. fabalis, but only with a 75% accuracy (Reid, 1996). Accuracy was greater if extreme forms were excluded. Juveniles of the two species are often very similar with thin shell walls, a sharp, fragile aperture rim and an unconstricted opening, and often the anterior (base of aperture) is drawn out into a moderate spout. As small juveniles lack penes, identification cannot always be verified. Association with verified adults, and shell size and colour, if on a shore where there is a large interspecific difference in these features, are usually the best guide 31Dof flic.kr/p/PZBccW & 32Dof flic.kr/p/R6s4KH .
Graham (1988) states that “a notch where the outer lip and last whorl meet” is indicative of L. obtusata, but its presence varies with age/spire development and it is not a reliable predictor of species (D. Reid, in litt.) 42Dof flic.kr/p/QGHDiw & 43Dof flic.kr/p/PZB3Fs .
8. Phenotypes of different wave exposures
On British rocky shores that have full marine salinity and fucoid algal growth, shell sizes and dominant colours of L. obtusata and L. fabalis vary with the degree of wave exposure. Image 44Dof flic.kr/p/Q3o4dM and its caption summarise approximately the most frequent correlations.
8 a. Sheltered shores, not estuarine, scale 8, 7 or 6, are the best for initial experience of differentiating the two species, providing the tidal range is sufficient to clearly separate and define a zone of Ascophyllum nodosum on the middle/upper shore and a zone of Fucus serratus on the lower shore (low spring tide required to expose) 45Dof flic.kr/p/QGHCb1 . Olivacea L. obtusata at its largest will probably be on the Ascophyllum, and easily differentiated from citrina L. fabalis at its smallest with thick aperture walls on the Fucus serratus 46Dof flic.kr/p/R6rYa4 . Unbiased samples can be obtained by shaking plants into a bucket. Juveniles of both species may be yellow and have a similar shape with an anterior spout 37Dof flic.kr/p/R3LbTo , but juveniles from Ascophyllum with adult L. obtusata will likely be that species and be as large as adult L. fabalis, and far larger than tiny juveniles of L. fabalis. If findings are as described, the identifications will almost certainly be correct, but examining the penes will add to experience. Sites with phenotypes as described can be found on the narrow inner portion of the Menai Straits between the two bridges and probably extending to Bangor and Y Felinheli; aerial photograph at data.nbn.org.uk/imt/?mode=SPECIES&species=NHMSYS00210... .
L. fabalis does not eat Fucus serratus, but uses the flat fronds as suitable feeding platforms for its diet of micro epiphytes and detritus. It is sometimes absent in sheltered situations, despite the presence of F. serratus, if excess sediment coats the plants, e.g. possible cause of absence in upper reaches of Severn Estuary (Williams, 1994). Where turbidity and sediment in estuaries 47Dof flic.kr/p/Rh3x7n or impact of sand laden currents 48Dof flic.kr/p/Rh3wNX prevent the growth of intertidal fucoid algae, both mollusc species are usually absent or very scarce.
8 b. Semi exposed shores, Ballantine scale 4, will provide experience at the opposite end of the phenotype sequence. Ascophyllum, a favoured food of L. obtusata, will be absent or present as a few scattered stunted plants, and L. obtusata will likewise be absent or present as small specimens on scant Fucus vesiculosus or other algae. Fucus serratus is still usually common at scale 4 and L. fabalis usually achieves its largest size here, sometimes equalling or exceeding any L. obtusata present. Differentiating the species can be very difficult on such shores because their sizes are often similar, the predominant colour form of both species is reticulata, and both tend towards larger apertures with thinner shells. Examination of penes is very necessary. An aerial photograph of this sort of shore open to a fetch across the Irish Sea of 100km to 175km, with a wide wave cut platform and plenty of F. serratus but no observed Ascophyllum, is at data.nbn.org.uk/imt/?mode=SPECIES&species=NHMSYS00210...! 0951H+G!0851H+G Large, reticulate L. fabalis were common here (penes checked). The aperture lip of adults was strongly thickened and the opening correspondingly narrowed. The interior was white 21Dof flic.kr/p/PYwgVE , sometimes tinted pink or violet and the exterior pattern often showed within the rim 49Dof flic.kr/p/QGHAn1 . No L. obtusata were found because they were absent or not detected among very similar L. fabalis. A thin shelled, wide apertured, citrina juvenile L. fabalis was initially mistaken for L. obtusata, but the white spirorbid like initial whorls and its presence among adult L. fabalis strongly suggested it was L. fabalis 50Dof flic.kr/p/R3L2LW .
8 c. Exposed shores, Ballantine scale 3, 2 & 1, usually lack either species, but L. fabalis may occur in dwarf form on scale 3 shores 51Dof flic.kr/p/QGHA9q & 28Dof flic.kr/p/PZBeay if sufficiently moist micro habitats exist with secure refuges for dwarfs to retreat into from violent waves. On some Scottish exposed shores with frequent splash and spray, it “may be found further up on the shore on other fucoids where there is adequate protection from desiccation” (McKay & Smith, 1979). It even sometimes occurs at mean high water neap level on Fucus spiralis (Sacchi, 1969 in Reid, 1996). It also occurs in exposed positions on Mastocarpus stellatus in Galicia, Spain; Palmeria palmata at Grindvik, Iceland; Devaleraea stellatus on Achill Island, Ireland; and on red encrusting algae and bare rock in northern Norway (Reid, 1996). On exposed shores, usually, the aperture is larger and the shell thinner than in other situations, and may resemble L. obtusata s.s. from moderately exposed shores.
In a sample of eight from a scale 3 site near Aberdeen, aerial image at data.nbn.org.uk/imt/?mode=SPECIES&species=NBNSYS00001... , all were fusca dwarfs, height mode 4.2mm, max. 5.5mm, with large apertures and thin shells apart from the wide columellar lip 51Dof flic.kr/p/QGHA9q . The spires varied greatly, some, like many L. fabalis, almost flat , others with a large bulging penultimate whorl well proud of the aperture that resembles many L. obtusata s.s..
9. Collecting and reliable recording, suggestions.
# Disregard stranded shells; their anatomy cannot be verified, they lack helpful habitat detail, the periostracum containing much colour may be eroded, and the shell may be bleached and weathered 17Dof flic.kr/p/R5n3xZ .
# If possible, start with a sheltered shore and then a semi exposed shore to gain experience.
# An individual specimen may have atypical features 51Dof flic.kr/p/QGHA9q or be deformed 52Dof flic.kr/p/Q3nXct , so examine several; for inspection of penes, eight mature ones give a 99% chance of both sexes if there is a 50:50 ratio.
# To obtain all colours and sizes, collect the sample randomly, e.g. by shaking plants into a bucket. If only the largest are selected by eye, the sample may be biased to females as they are larger than males on average, especially L. fabalis on sheltered shores.
# Take separate clearly labelled samples from discrete habitats e.g. Ascophyllum and F. serratus zones. Be aware that some shores have more than one wave exposure; see Reimchen (1981), link in references.
# Transport specimens in sealed plastic boxes dampened, but not awash, with seawater.
Store in a fridge at about 6ºC and examine as soon as possible; L. obtusata s.s. exposes itself more readily when damp rather than when submerged.
# Check any shell based identification with examination of some penes.
# When submitting records to a recording scheme, make sure to include that the penes were examined so that at a future date your record can be separated from the mass of less reliable records. Check with the scheme organizer that the detail will be included
when entered. Records submitted to the Marine Recorder of the Conchological Society of G.B. & Ireland have anatomical notes included and uploaded as integral parts of the record; contact marine@conchsoc.org . Other detail such as shore exposure and algal zone are also helpful and welcomed. Clear photographs of shell aperture and penes, or preserved specimens, are valued by the Marine Recorder.
10. Acknowledgements
I am indebted to Dr David Reid for his careful examination of this account and for his highly valued advice, but any errors or omissions are my (IFS) responsibility.
I wish to thank Simon Taylor, Marine Recorder for the Conchological Society of G.B. and Ireland, for helpful discussion and the provision of specimens and photographs, and I am grateful to Dr Jan Light for help with literature and specimens.
11. References and web links
Ballantine, W.J. 1961. A biologically-defined exposure scale for comparative description of rocky shores. Field studies 1(3): 1-19. www.field-studies-council.org/resources/field-studies-jou...
Carvalho, J., Sotelo, G., Galindo, J. & Faria, R. 2016. Genetic characterization of flat periwinkles (Littorinidae) from the Iberian Peninsula reveals interspecific hybridization and different degrees of differentiation. Biol. J. Linn. Soc., 118: 503 to 519. onlinelibrary.wiley.com/doi/10.1111/bij.12762/abstract
Goodwin, B.J & Fish, J.D. 1977. Inter- and intraspecific variation in Littorina obtusata and L. mariae (Gastropoda, Prosobranchia). J. Moll. Stud. 43: 241 to 254. Extract at mollus.oxfordjournals.org/content/43/3/241.extract
Graham, A. 1988. Molluscs: prosobranch and pyramidellid gastropods: keys and notes for the identification of the species. Brill & Backhuys, for Linn. Soc. Lond. & Estuarine and Brackish-water Sciences Assoc. Synopses of the British Fauna (New Series) no.2. Edition 2 (662pages). Leiden.
Hayward, P.J. & Ryland, J.S. (eds.) 1990. The marine fauna of the British Isles and North-West Europe. Volume 2. Clarendon Press, Oxford.
Hayward, P.J. & Ryland, J.S. (eds.) 1995 and reprints to 2009. Handbook of the marine fauna of North-West Europe. Oxford University Press, Oxford.
Jeffreys, J.G. 1865. British conchology. vol.3. London, van Voorst. (L. fabalis included in L. obtusata as var. fabalis.)
archive.org/stream/britishconcholog03jeffr#page/356/mode/1up
Jeffreys, J.G. 1869.British conchology. vol.5. London, van Voorst. Plate ci, fig.8 of Littorina obtusata var. aestuarii (As Littorina aestuarii) from Shottisham Creek, R. Deben, near Felixstowe, Suffolk. Abundant there between tide marks. Well developed spire. (Now extinct or nearly so.) archive.org/stream/britishconcholog05jeffr#page/n489/mode...
McKay, D.W. & Smith, S.M. 1979. Marine Mollusca of East Scotland. Royal Scottish Museum, Edinburgh. [An early adoption of the differentiation as L. littoralis (for L. obtusata s.s.) and L. mariae (for L. fabalis) before nomenclature became settled. Maps reliable as all entries made or vetted by the experienced authors.]
Reid, D.G. 1996. Systematics and evolution of Littorina. Ray Society, London.
www.raysociety.org.uk/publications/zoology/the-systematic...
Reimchen, T.E. 1981. Microgeographical variation in Littorina mariae Sacchi & Rastelli and a taxonomic consideration. J. Conch. Lond. 30: 341 to 350.
www.web.uvic.ca/~reimlab/Microgeographical%20Variation-00...
Sacchi, C. F. & Rastelli, M. 1966. Littorina mariae, nov. sp.: les differences morphologiques et ecologiques entre "nains" et "normaux" chez l'espece L. obtusata (L.) (Gastr., Prosobr.) et leur signification adaptive et evolutive. Atti Soc. Ital. Sci. Nat. 105: 351 to 369.
Smith, D.A.S., 1976. Disruptive selection and morph-ratio clines in the polymorphic snail Littorina obtusata (L.) (Gastropoda: Prosobranchia). J. Mollus. Stud. 42: 114 to 135.
Smith, I.F. 2012. Anatomy of marine gastropods without dissection.
Mollusc World 28: 13 to 15. Conch. Soc. GB & Ireland.
Smith, I.F. 2016. Revision of Smith, I.F. 2012. Anatomy of marine gastropods without dissection. flic.kr/s/aHskNP6GoL and pdf version at www.researchgate.net/publication/310467378_Anatomy_of_mar...
Williams, G.A. 1990. The comparative ecology of the flat periwinkles, Littorina obtusata (L.) and L. mariae Sacchi et Rastelli in Field Studies 7: 469 to 482. fsj.field-studies-council.org/browse-by-category/marine-b... (scroll down to 1990) [Fig. 2 has an exposure scale in reverse order of Ballantine scale so 1 = Ballantine 8; and caption error: closed boxes are L. obtusata, open boxes are L. mariae/fabalis.]
Williams, G.A. 1994. Variation in populations of Littorina obtusata and Littorina mariae (Gastropoda) in the Severn Estuary. Biol J Linnean Soc 51: 189 to-198.
onlinelibrary.wiley.com/doi/10.1111/j.1095-8312.1994.tb00...
12. Glossary
3Dof = Image 3 in Flickr album.
allometric (adj.) = of disproportionate growth of a part or parts of an organism as the whole organism grows.
aperture = mouth of gastropod shell; outlet for head and foot.
coll. = in the collection of (named person or institution; compare with leg.).
columella = solid or hollow axial “little column” around which gastropod shell spirals; hidden inside shell, except on final whorl next to lower part of inner lip of aperture where hollow ones may end in an umbilicus or siphonal canal.
columellar (adj.) = of or near central axis of coiled gastropod.
columellar lip = lower (abapical) part of inner lip of aperture.
columellar muscle = large muscle connecting foot/head of gastropod to its shell at the columella.
distal = positioned or facing away from midline of body.
epiphyte = an organism growing on a larger plant for support, but not nutrition.
epizooic (adj.) = of non-parasitic organisms living on surface of animals.
filament = a slender threadlike object or fibre in animal or plant structures.
filament (in Reid, 1996) = glandless tip of penis a.k.a. distal tubule. Often not threadlike.
flagellum = threadlike organ or appendage.
height (of gastropod shells) = distance from apex of spire to base of aperture along/parallel to axis of coiling (see flic.kr/p/R6s1kr ).
in litt. (abbreviation of Latin “in litteris”) = in unpublished correspondence.
leg. (abbreviation of legit) = collected/ found by (compare with coll.)
mamilliform = shaped like a nipple.
mesial = facing towards the midline of the body.
mobile = able to move self, e.g. a horse, or to be moved by an agent, e.g. a wave or a cell phone.
motile = moves self spontaneously without volition; applicable to whole animals or to parts of them such as cells, gametes, penes or cilia.
penes (plural of penis) = male copulatory organs.
phenotype = form of a species resulting from influence of particular environmental factors.
proximal = towards the centre of the body or point of attachment.
sensu lato (abbreviation s.l.) = in the wide sense, possibly an aggregate of more than one species.
sensu stricto (abbreviation s.s.) = in the strict sense, excluding species that have been aggregated or confused with it.
spire = all whorls of a gastropod shell, except the final body whorl. But in this account, “spired shells” are taken to be those with a pointed apex protruding beyond the body whorl rather than the domed spire of some that extends beyond the body whorl.
taxonomic (adj.) = of or relating to taxonomy.
taxonomy = the description, identification, naming, and classification of organisms.
vermiform = shaped like a worm.
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