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Watch it vimeo.com/28304264

  

I combined everyday soap bubbles with exotic ferrofluid liquid to create an eerie tale, using macro lenses and time lapse techniques. Black ferrofluid and dye race through bubble structures, drawn through by the invisible forces of capillary action and magnetism.

 

Time-lapse sequences: Nikon D90, Nikkor 60mm macro lens and custom built intervalometer.

Motion-control: Arduino driven scanner platform and mirror rigs

Score: Ableton Live

This species happens in premontane very wet forest, from 1200 to 1800 meters, but most of time, the plants are hanging from a few roots to some trunk, that is why this is a very tricky species to grow.

 

The flower is 8 to 10mm across and the plant, at this time, is 30cms (pendent as shown). It was very difficult to shot the plant!

Rewarding my sprained ankle with a decent view after a surprisingly successful 8-hour day on it. VA10.

Netherlands, Scheveningen, HTM Bus.

 

In transit to the 'Netkous' RandstadRail station with Leun.

+++ DISCLAIMER +++

Nothing you see here is real, even though the conversion or the presented background story might be based historical facts. BEWARE!

 

Some background

After Mil Helicopters' Mi-28 combat helicopter did not find takers, the design bureau decided in the 2000s to take a huge development step forward and question the basic helicopter layout. The result was the Mil Mi-62 (NATO reporting name: Hepcat), a single-seat attack gyrodyne/compound helicopter: a VTOL aircraft with a helicopter-like rotor system that is driven by its engine for take-off and landing but basically relies on conventional means of propulsion to provide forward thrust during cruising flight. Lift during forward flight is provided by a combination of the rotor, like an autogyro, as well as conventional wings, even though these alone would not keep the aircraft in the air.

 

The Mi-62 featured a tip-jet-powered rotor that burned a mixture of fuel and compressed air, bled from two wing-root-mounted jet engines. The rotor was only driven during the start/landing phase and at low speed. The air for the rotor was produced by compressors driven through a clutch off the main engines, though, which was fed through ducting up to the rotor head. Two Progress AI-222-25 turbofans, each rated at 24.52 KN (5.512 lbf), provided thrust for translational flight while the rotor autorotated, enabling VTOL and STOL start with overload. The cockpit controls included a cyclic and collective pitch lever, as in a conventional helicopter.

 

Each engine supplied air for a pair of opposite rotor blades. The rotor blades were a symmetrical airfoil around a load-bearing spar. The airfoil was made of carbon fiber and light alloy because of center of gravity concerns. The compressed air was channeled through three tubes within the blade to tip-jet combustion chambers, where the compressed air was mixed with fuel and burned, driving the rotor. As a torque-less rotor system, no anti-torque correction system was required. Propeller pitch was controlled by the rudder pedals for low-speed yaw control. To support handling at low speed, bleed air from the main engines was also ducted to a control vent system in the tail.

 

Transition from helicopter to autogiro took place at around 60 mph by extinguishing the tip-jets, and at higher speeds up to half the lift was provided by the fixed wings. At high cruising speed, the Mi-62 almost behaved like a standard aircraft. Cruising speed was to be at about 500 km/h (312 mph), coupled with a range of up to 1400 km (870 ml).

 

Since the speed of the advancing rotor tip is a primary limitation to the maximum speed of a helicopter, this arrangement allowed a faster maximum speed than pure helicopters such as the Mi-24/35 or the AH-64. The elimination of the tail rotor is a qualitative advantage, too, because the torque-countering tail rotor can use up to 30% of engine power. Furthermore, the vulnerable boom and rear gearbox are fairly common causes of helicopter losses in combat. The Mi-62’s entire transmission presents a comparatively small target to ground fire, and is a rather simple/rigid arrangement with much less moving parts than a standard helicopter.

 

The Mi-62 was designed as an alternative to Kamov's successful Ka-50/52 program, and regarded as a heavier alternative. While the Ka-50 was designed to be small, fast and agile to improve survivability and lethality, the Mi-62 was to rely on speed, quick acceleration and decelleration as well as on good low altitude handling, coupled with sufficient protection against small caliber weapons. Since operation would be primarily at low level and using the landscape as cover, not much emphasis was put on stealth features, even though many passive protection elements like RAM were incorporated into the aircraft.

 

One of the program priorities was to enhance the helicopter's survivability. With this goal in mind, the configuration and systems' arrangement were chosen, assemblies designed, and structural materials tested, beyond the robust rotor propulsion system. The following measures to enhance pilot survivability were taken:

 

• Engines were placed on both sides of the airframe to prevent a single hit from destroying both engines

• The gyroplane could fly on a single engine in various modes – even with a damaged rotor a controlled landing glide was possible

• The cockpit was armored and screened with combined steel/aluminum armor and armored Plexiglas

• The hydraulic steering system compartment was armored and screened

• Vital units were screened by less important ones

• Self-sealing fuel tanks were filled with polyurethane foam

• Composites were used to preserve the helicopter's efficiency when its load-carrying elements are damaged

• A two-contour rotor-blade spar was developed, integrating the air ducts

• Control rod diameter was increased by positioning most of them inside the armored cockpit

• The powerplant and compartments adjacent to the fuel tanks were fire-protected

• The hydraulic system is capable of operating for 30 minutes if the oil system is damaged

• The power supply systems, control circuits etc. were made redundant and placed on opposite sides of the airframe

 

The armor consisted of spaced-aluminum plates with a total weight of more than 300 kg. The armor is fitted into the fuselage load-bearing structure, which reduces the total weight of the helicopter. GosNIIAS tests confirmed the pilot's protection up to 20mm caliber cannon rounds and shell fragments.

 

Another unique feature of the Mi-62 is the use of a rocket-parachute ejection system in case of an emergency. The helicopter emergency-escape system uses the K-37-800 ejection seat that was developed by the Zvezda Scientific Production Association (Chief Designer Guy Severin). The pilot's safety was also ensured by the undercarriage design. The undercarriage is capable of absorbing large loads in an emergency landing, and the cockpit has a crunch zone of up to 10-15% upon impact.

 

Basic armament consists of a twin-barreled Sh2A42 30-mm gun. The gun is mounted in a shallow turret which can rotate full 360° near the center of fuselage. It has 460 rounds of ammunition, firing high-fragmentation, explosive incendiary rounds and armor-piercing rounds.

The cannon has a dual-feed, which allows for a cyclic rate of fire between 300 to 900 RPM. Its effective range varies from 1500 meters for ground vehicles to 2,500 meters for air targets. Stated penetration for the 3UBR8 is 25 mm of RHA at 1,500 meters.

 

Beyond that, the aircraft carries a substantial load of weapons in six external hardpoints under the stub wings. An total of some 2.000 kg mixed ordnance, including AAMs, AGMs, gun and unguided rocket pods which include the S-13 and S-8 rockets, can be carried. Even unguided and guided (IR, optical, laser) bombs have been successfully tested, so that the Mi-62 could eventually replace early Su-25 combat aircraft in the CAS role. The "dumb" rocket pods can be upgraded to laser guided with the proposed Ugroza system.

 

The main armament against moving ground targets consists of up to sixteen laser-guided Vikhr anti-tank missiles (transl. Vortex or whirlwind) with a maximum range of some 8 km. The laser guidance is reported to be virtually jam-proof and the system features automatic guidance to target, enabling evasive action immediately after missile launch.

 

Like the Ka-50, the Mil gyrodyne was from the outset to be operated by a single pilot only. Mil’s designers concluded after thorough research of helicopter combat in Afghanistan and other war zones that the typical attack mission phases of low-level approach, pop-up target acquisition and weapon launch would not simultaneously demand navigation, maneuvering and weapons operation of the pilot. Thus, with well-designed support automation, a single pilot was expected to carry out the entire mission alone.

 

During operational testing from 1995 to 1996 the workload on the pilot was found to be similar to that of a fighter-bomber pilot, and the pilot could perform both flying and navigation duties. Later flight tests of the Mi-62 prototypes proved that its handling was more like an aircraft with VTOL capabilities than a standard helicopter, so that jet pilots could master it with some training.

 

Initially the Mi-62 was to be have been fitted with the Merkury Low-Light TV (LLTV) system. Due to a lack of funding, the system was late and experienced reliability and capability issues. As a result, focus shifted to Forward Looking Infra-Red (FLIR) systems, including the Shkval-N sighting system with an infrared sensor. Many versions were tried; on some the original "Shkval" was supplemented by a thermal imaging system, while others saw a complete replacement by the "Samshit" day-and-night system, which has become the final sensor standard, mounted in a chin sensor turret.

 

The fire control system automatically shares all target information among the four Mi-62 of a typical flight in real time, allowing one helicopter to engage a target spotted by another, and the system can also input target information from ground-based forward scouts with personnel-carried target designation gear.

 

The Mi-62 was, after a lengthy development and constant lack of funds, eventually adopted for service in the Russian army in 2015. It is currently manufactured by the new Russian Helicopters company that was founded in 2009 in Moscow, and built at the Mil Moscow Helicopter Plant. It has been introduced to both Air Force (Mi-62 sans suffix, ‘Hepcat A’) and Naval Aviation (Mi-62K, ‘Hepcat B’) and is being used as a heavily armed attack helicopter against both ground and airborne targets.

 

The navalized Mi-62K derivative has been selected as the new ship-borne attack type for the Russian Naval Aviation (Aviatsiya Voenno-morskogo Flota Rossii). It will feature folding rotor blades and life-support systems for the crew, who will fly in immersion suits. The fuselage and systems will be given special anti-corrosion treatment and a new fire-control radar will be capable of operating in "Sea Mode" and of supporting anti-ship missiles. Aviatsiya Voenno-morskogo Flota Rossii will need no fewer than 20 Mi-62, which will be operated together with Ka-52Ks.

 

The first Mi-62K is tentatively slated to enter squadron service by late 2014 or early 2015, coinciding with the delivery of the first carrier of the new Mistral class amphibious assault ships, ordered by the Russian Defense Ministry. These small carriers will contain rotary-wing assets, formed into aviation groups, and each of these groups is planned to include eight attack and eight assault/transport helicopters.

  

General characteristics

Crew: One

Length (fuselage only): 13,46 m (44 ft 1 in)

Rotor diameter: 15,40 m (50 ft 5 1/2 in)

Height: 4.60 m (15 ft 1 in)

Disc area: 186.3 m² (1.998 ft²)

Empty weight: 7,700 kg (17,000 lb)

Loaded weight: 9,800 kg / 10,400 kg (21,600 lb / 22,930 lb)

Max. takeoff weight: 10,800 kg (23,810 lb)

Powerplant

2× Progress AI-222-25 turbofans, 24.52 KN (5.512 lbf) each plus

4× rotor tip jet burning compressed air/fuel, 4.4 kN (1,000 lbf) thrust each

Performance

Never exceed speed: 550 km/h (297 knots, 342 mph) in dive

Maximum speed: 515 km/h (278 knots, 320 mph) in level flight

Cruise speed: 370 km/h (200 knots, 230 mph)

Range: 545 km (339 ml)

Combat radius: 800 km (500 ml)

Ferry range: 1400 km (870 ml) with 4 drop tanks

Service ceiling: 5,500 m (18,000 ft)

Rate of climb: 10.7 m/s (2,105 ft/min)

 

Armament

1× turret-mounted, wtin-barreled 30 mm Shipunov Sh2A42 cannon (460 rounds total, dual feeding AP or HE-Frag) under the fuselage

6×wing hardpoints with a capacity of 2,000 kg and provisions to carry combinations of launch pods for 80 mm S-8 rockets or 122 mm S-13 rockets, APU-6 Missile racks or up to 20× 9K121 Vikhr anti-tank missiles, 6× Vympel R-73 (NATO: AA-11 Archer) air-to-air missiles, Kh-25 semi-active laser guided tactical air-to-ground missiles, 4× 250 kg (550 lb) bombs or 2x 500 kg (1,100 lb) bombs, plus 23 mm UPK-23-250 gun pods (240 rounds each) or 500 l (130 US gal) external fuel tanks.

Two compartments in the lower fuselage with flare and chaff countermeasure dispensers, typically 4× UV-26 dispensers each (total 512 chaff/flare cartridges in each pod)

  

The kit and its assembly:

Another entry for the “Za Rodinu - The Anthony P Memorial Build” at whatifmodelers.com, and this time it’s a modern and rather exotic whif. Helicopters are rare among whiffers, so I thought I’d give that subject a chance, and I actually had the basis kit in store for some time, as I intended to build it for another GB but never got that kick to start it.

 

The fictional Mi-62 is a conversion of a snap-fit kit from Kotobukiya from a series of generic, roughly 1:72 scale mecha vehicles that do not belong to a specific series or movie, but they seem to be intended to go well with Gundam or Dougram. These are rather toy-like, sturdy things, but they have potential for more – especially the gyroplanes (two different types exist).

 

These seem to be unmanned drones/UAVs, though, and that immediately leads to the conversions I made. Most important change is a manned cockpit with a clear canopy (from a KP Su-25) and the respective, scratched interior.

 

Another big change was the deletion of the original, gigantic gatling gun under the fuselage, replaced by a much smaller twin cannon turret. That left a lot of ground clearance – as a late modification I decided to chop the landing gear and the respective fin/wing endplates by more than 1cm, so that the gyroplane would sit closer to the ground.

 

Further small cosmetics include an asymmetrical radome and a protruding pitot boom, some antenna bulges, new engine exhausts, chaff dispensers in the fuselage flanks, and free-standing main wheels.

 

The ordnance comes from a Dragon Soviet-Air-To-Ground-Ordnance kit, hung onto six new wing hardpoints (from a 1:144 F-4E and an ESCI Ka-34 in 1:72, IIRC).

  

Painting and markings:

Choosing a proper scheme was tricky. The helicopter was to look realistic, but still exotic, at least for Russian standards. I considered various options:

● An all-mid-grey livery, inspired by current Mi-35 attack helicopters. Too dull & simple!

● A trefoil-style scheme in khaki and olive drab, with blue undersides. Flashy, but IMHO rather old-school.

 

I finally found an original scheme on a Ka-62 prototype (shown at MAKS-2009): a wraparound scheme in olive drab, medium grey and chocolate brown. The colors are enamels, I used Olive Drab ANA 613 (ModelMaster #2050), German Uniform “Feldgrau” (ModelMaster #2014) Grey and German Armor Red Brown (Humbrol 160), later highlighted through dry-brushing with lighter shades of the basic tones and a black ink wash, standard process.

 

The interior was to be Russian-style, too, but instead of the eye-boggling turquoise I went for PRU Blue (Humbrol 230) inside of the cockpit. Still looks odd, but it’s not so bright.

 

As a twist I decided to use Russian Navy markings – and the real world introduction of Mistral Class ships was a good excuse for a naval version of this attack helicopter. The Naval Aviation used to and does employ many land-based aircraft and helicopters, incl. e. g. the Mi-24, in similar liveries to the Air Force or Army cousins.

 

The markings were puzzled together from various aftermarket decal sheets from Begemot , Authentic Decals and TL Modellbau, as well as from the scrap box. After some additional dry-brushing with medium grey overall, the kit was sealed with a coat of matt acrylic varnish.

Camera: Leica M10

Lens: SUMMILUX-M 1:1.4/50 ASPH. E46 4203500

Retouch: Lightroom Classic CC 7.2

Option: VISOFLEX

Still frame from final cut of Compressed 02 vimeo.com/28304264

The black sphere waits.

 

Still frame from final cut of Compressed 02 short.

Piping system with valves for compressed air. Ended up looking very creepy and strange after processing.

 

Featured in Explore January 13, 2008 #287

 

Gear:

Canon 30D

Canon EF 24-70 f/2.8L USM

Test scene.

 

High-quality JPEG exported from a compressed RAW file.

 

See the full article on Analog Senses:

www.analogsenses.com/2015/11/18/first-impressions-on-the-...

Taken from right-to-left, as I was sitting on the north side of the train, headed west.

 

I really like what happened when I set the camera on my phone to 'panorama' and then held it stationary against the window of the train: (from an email I wrote) "The camera accrues the image unevenly: it's looking for motion but its internal gyroscope ("accelerometer") is confused. If things aren't changing much in the foreground, the picture 'piles up' and the horizon stutters, but water or trees close-by trigger a richer capture

This was just after sunrise. Fall colours here, and lots of standing water."

Las Vegas Skyline

 

City of Las Vegas

 

Location: Las Vegas, Nevada, United States of America

 

Landscape Shots of Las Vegas

 

Taken with Olympus OM-D Camera

 

Taken in November 2020

 

#LasVegas

#Vegas

#LasVegasNevada

#SinCity

#GamblingCapital

#GamblingParadise

#GamblingMecca

#PartyCity

#Landscape

#LandscapePhotos

#LandscapePhotography

#LandscapePictures

#LandscapeShots

#Olympus

#OlympusCamera

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#OlympusOMD

#OlympusPhotos

#City

#CityScape

#CityScapes

#CitySkylines

#Skylines

#Urban

#UrbanSkylines

#UrbanJungle

 

All photos are compressed and resolution is reduced.

  

Taken by Claude T. Photography - linktr.ee/Claude_T_Photography - www.flickr.com/people/claude_t_photography/ - Instagram: claude_t_photography - www.instagram.com/claude_t_photography

   

Residential architecture.

wooden dutch houses reflected

Tube trailer used to transport compressed gases.

Compressed at 145% speed to meet the maximum 3 minutes.

PENTAX K-1

ASAHI OPT. SMC PENTAX 1:1.4/50

How to create an encrypted zip file on Linux

 

If you would like to use this photo, be sure to place a proper attribution linking to xmodulo.com

Early juveniles in August when all or most adults dead. Similar form to adults, but periostracum thinner and paler, and spire protrudes less.

Maximum dimension 4.1 mm and 3.3 mm, Portlethen, north-east Scotland, August 1970.

 

Full SPECIES DESCRIPTION BELOW

Revised PDF available at www.researchgate.net/publication/372768813_Lacuna_pallidu....

Sets of OTHER SPECIES at: www.flickr.com/photos/56388191@N08/collections/

  

Lacuna pallidula (da Costa, 1778)

 

Synonyms: Cochlea pallidula da Costa, 1778; Lacuna neritoidea Gould, 1840; Lacuna patula Thorpe, 1844; Lacuna retusa Brown.

Current taxonomy: WoRMS www.marinespecies.org/aphia.php?p=taxdetails&id=140168

Vernacular: Pallid chink shell; Pale lacuna; Gwichiad agennog gwelw (Welsh); Lacuna pâle (French); Lavspiret grubesnegl (Danish); Bleke scheefhoren (Dutch); Blek lagunsnäcka (Swedish).

 

Shell description

The largest dimension of female shells is up to about 12 mm fig. 01 flic.kr/p/2kNQ7pc and males grow to 6 mm. The species has an annual life cycle; all or most adults are dead by June. Their small juvenile offspring occur in summer fig. 02 flic.kr/p/2kGH2G9 , growing to full size in winter. The body whorl forms the great majority of the shell, and the very small spire is sunk below the upper margin in most views. Juveniles are similar in form with a slightly lower spire. Sutures between the whorls are distinct. The smooth surface has no sculpture apart from numerous, growth lines.

One face of the hollow columella is missing, exposing a long wide columellar groove (lacuna, chink or canal), leading to a large funnel-like umbilicus fig. 03 flic.kr/p/2kNL1YB . On some specimens the columellar groove is indistinct and the umbilicus reduced fig. 04 flic.kr/p/2kNPCc9 and fig. 05 flic.kr/p/2oQ83ra .

The very large ‘D’ shape aperture is as high as the whole shell, and it occupies about 75% of the area in apertural-view images fig. 01 flic.kr/p/2kNQ7pc . The palatal lip is semi-circular, and it continues along the abapertural side of the columellar groove. The wide, white columellar lip forms the adapertural edge of the groove fig. 03 flic.kr/p/2kNL1YB .

The ‘D’ shape operculum is a rapidly expanding oligogyrous spiral with its off-centre nucleus close to the base of the columellar lip. It is transparent, tinted yellow fig. 04 flic.kr/p/2kNPCc9 & fig. 06 flic.kr/p/2kNL1Ut or nearly colourless fig. 05 flic.kr/p/2oQ83ra . The substantial periostracum is olive-brown with distinct growth lines on large specimens fig. 07 flic.kr/p/2kNQ773, and it usually extends beyond the lip of the aperture fig. 04 flic.kr/p/2kNPCc9 . Under the periostracum, the calcareous shell is white or yellowish white fig. 01 flic.kr/p/2kNQ7pc . Live adults with a thick opaque periostracum are olive-green/brown in water fig. 08 flic.kr/p/2kNPC3g becoming dull brown when dead and dried fig. 01 flic.kr/p/2kNQ7pc . There are no coloured bands or variegation at any stage.

 

Body description

The flesh is translucent white with varying amounts of yellow or pink tinting fig. 07 flic.kr/p/2kNQ773 and fig. 05 flic.kr/p/2oQ83ra . The snout is ventrally slit fig.06 flic.kr/p/2kNL1Ut and usually rolled into a cylinder fig. 09 flic.kr/p/2oQ92WM . The extended cephalic tentacles are long, smooth, translucent whitish and taper to a blunt tip. When contracted they wrinkle and any yellow tint is intensified fig. 08 flic.kr/p/2kNPC3g . There is a black eye on a slight bulge at the base of each tentacle fig. 07 flic.kr/p/2kNQ773 . The roof of the mantle cavity is whitish translucent showing the colour of the shell except for the mantle edge which is thick and sometimes yellowish fig. 09 flic.kr/p/2oQ92WM . The foot is white with varying amounts of yellow or pink fig. 07 flic.kr/p/2kNQ773 , especially on the opercular disc which supports, and is visible under and through, the transparent operculum fig. 05 flic.kr/p/2oQ83ra and fig. 09 flic.kr/p/2oQ92WM . The two small, flat metapodial tentacles protrude beyond the posterior of the operculum fig. 09 flic.kr/p/2oQ92WM .

 

Key identification features

Lacuna pallidula

1) Columellar groove (lacuna or chink) leads to umbilicus fig. 01 flic.kr/p/2kNQ7pc but is sometimes sealed over fig. 04 flic.kr/p/2kNPCc9 .

2) Largest dimensions up to 12 mm (female) and 6 mm (male). Hardly any of the spire protrudes beyond the body whorl fig. 01 flic.kr/p/2kNQ7pc

3) Very large ‘D’ shape aperture equals shell height and occupies about 75% of area in apertural view fig. 01 flic.kr/p/2kNQ7pc.

4) Shell olive-brown with no spiral bands fig. 08 flic.kr/p/2kNPC3g .

5) Body white fig. 07 flic.kr/p/2kNQ773 , sometimes yellowish or pinkish; no grey stipple.

6) Found mainly on Fucus serratus and sometimes on Laminaria.

 

Similar species

Lacuna parva (da Costa, 1778) fig. 10 flic.kr/p/2kNL1A2 .

1) Columellar groove (“lacuna” or “chink) leads to umbilicus. 2) Usual maximum height 4 mm; sometimes 6 mm. Spire 30% to 40% of shell height.

3) Aperture occupies about 50% of area in apertural-view images.

4) Body whorl has three brown spiral bands; basal band 1 easily overlooked if base of shell not examined. Some shells are uniform white or brown with no bands.

5) Body translucent white, usually stippled grey.

6) Found mainly, especially when young, on small red weeds. Sometimes on fucoids.

 

Littorina fabalis (W. Turton, 1825) and

L. obtusata (Linnaeus, 1758) fig. 11 flic.kr/p/2kNPBJk .

1) No columellar groove or umbilicus.

2) Maximum dimension up to 17 mm. Very large body whorl and small spire.

3) Aperture occupies about 50% of area in apertural-view images.

4) Shell of L. obtusata is sometimes greenish olive.

5) Body varied shades of yellow, brown or black.

6) Found on Fucus serratus (L. fabalis) or Ascophyllum (L. obtusata) and on Fucus vesiculosus (both).

 

Lacuna vincta (Montagu, 1803) fig. 12 flic.kr/p/2kNQ6PK .

1) Columellar groove (“lacuna” or “chink”) leads to umbilicus. 2) Maximum height about 10 mm. Well developed spire about 50% of adult shell height, and about 30% on juveniles less than 3 mm high.

3) Aperture occupies about 30% of area in apertural-view images of full grown adults.

4) Body whorl has four brown spiral bands.

5) Body whitish with grey, yellow, orange and/or aquamarine parts.

6) Found on Laminaria and, especially juveniles, on small red weeds. Also on Zostera and sometimes on fucoids.

 

Lacuna crassior (Montagu, 1803) fig. 13 flic.kr/p/2kGH26u

1) Wide white columellar shelf. Usually no groove or umbilicus but sometimes small ones present.

2) Distinct spire about 50% of mature shell height, about 45% when younger.

3) Aperture occupies about 30% of area in apertural view.

4) Shell when live, has translucent, yellowish-brown spire and brownish-white body whorl. Thick periostracum has distinct, raised, transverse (costal) ridges. Dead dry shells are dull yellowish-brown if periostracum retained, yellowish white with faint spiral lines if periostracum worn off.

5) Body translucent whitish.

6) A rare species which often associates with the bryozoan Alcyonidium diaphanum.

 

Habits and ecology

L. pallidula feeds on the surface of Fucus serratus (Smith, 1973) and Laminaria (Lebour, 1937) near low water on rocky shores and to 70 metres depth. It is usually absent where turbidity or soft substrate prevents growth of F. serratus. It cannot survive desiccation. Some populations live in the Baltic in salinity down to 12‰.

It moves with a bipedal stepping motion, lifting alternately the right and left sides of the foot. It breeds in late winter and spring, sometimes extending into summer and autumn, with a maximum in February to May in Britain, but precise dates vary regionally. The spawn mass is a low gelatinous dome with an almost circular, oval base (not kidney-shape), diameter 3.9 mm to 5.3 mm (Lebour, 1937), laid on fronds of F. serratus or Laminaria. There are up to about 200 ova per spawn mass fig. 14 flic.kr/p/2kNQ71M . In the low salinity Øresund, Denmark, the masses are smaller with as few as 13 ova (Thorson, 1946 in Fretter & Graham, 1962).

Fretter and Graham (1962) reported confusion with the spawn of “Littorina littoralis” (the name mistakenly used formerly by British authors for an aggregate of Littorina obtusata and L. fabalis). The limited material examined for this account suggests the confusion is with L. fabalis which lives on F. serratus at the same shore level and lays similar, almost circular oval spawn masses, while L. obtusata lives higher up the shore, favouring Ascophyllum, and often lays kidney-shaped spawn masses up to 7 mm long. The difference between the spawn masses of L. fabalis and Lacuna pallidula may be that the latter has a distinctly bevelled peripheral rim while the surface of the former slopes to the substrate without a break in slope fig. 14 flic.kr/p/2kNQ71M . But more investigation is required to test these suggestions; the difference might be due to age of spawn mass. Lacuna parva also has similar spawn but it is found on red algae and is smaller, about 2.5 mm diameter with about 50 ova in Britain fig. 14 flic.kr/p/2kNQ71M ; 2.2 mm to 2.5 mm with 6 to16 ova in the brackish Øresund (Ockelmann & Nielsen, 1981 in Wigham & Graham, 2017).

The individual egg capsules of L. pallidula become angular as they swell and become crowded and compressed. There is no planktonic veliger stage; young emerge as tiny crawling snails. Through a microscope, just before hatching, two tentacular extensions of the opercular disc protruding beyond the operculum may be detected on the embryos within the clear capsules (Fretter & Graham, 1962). Males die after mating, and the females about a month later, so all or most adults breeding in the main period are dead by June or July, and few specimens over 5 mm high can be found in August fig. 02 flic.kr/p/2kGH2G9 . Both sexes grow rapidly until October. From October to February males grow slowly, but females at three times their rate so that by breeding time they are over twice as high as males (Thorson, 1946 in Fretter & Graham, 1962). When mating, the small male rides on the female’s shell near the aperture with his penis inserted into her mantle cavity.

 

Distribution and status

L. pallidula occurs from northern Norway and Iceland to Atlantic Spain and New England (USA). GBIF map www.gbif.org/species/2301181

It is found all around Britain and Ireland, but is scarce or absent in the north-eastern Irish Sea and southern North Sea where lack of hard substrate and/or turbidity hinder the growth of Fucus serratus and Laminaria. UK distribution map NBN species.nbnatlas.org/species/NBNSYS0000175975#tab_mapView

 

Acknowledgements

For use of an image, I thank Rob Durrant.

 

References and links

Forbes, E. & Hanley S. 1849-53. A history of the British mollusca and their shells. vol. 3 (1853), London, van Voorst. archive.org/details/historyofbritish03forbe/page/56/mode/2up

Also plate LXX11 at end of vol.4, fig. 1 & 2, also fig. 3 & 4 labelled “L. patulaarchive.org/details/historyofbritish04forbe/page/n459/mod...

 

Fretter, V. and Graham, A. 1962. British prosobranch molluscs. London, Ray Society.

 

Graham, A. 1988. Molluscs: prosobranch and pyramidellid gastropods. Synopses of the British Fauna (New Series) no.2 (Second edition). Leiden, E.J.Brill/Dr. W. Backhuys. 662 pp.

 

Jeffreys, J.G. 1862-69. British conchology. vol. 3 (1865). London, van Voorst.

archive.org/details/britishconcholog03jeffr/page/350/mode...

 

Lebour, M.V. 1937. The eggs and larvae of the British prosobranchs with special reference to those living in the plankton. J. mar. biol. Ass. U.K., 22: 105 – 166. plymsea.ac.uk/953/

 

Ockelmann, K. W. and Nielsen, C. 1981. On the biology of the prosobranch Lacuna parva in the Øresund. Ophelia 20: 1-16.

Abstract at www.tandfonline.com/doi/abs/10.1080/00785236.1981.10426559

 

Smith, D. A. S. 1973. The population biology of Lacuna pallidula (da Costa) and Lacuna vincta (Montagu) in north-east England. J. mar. biol. Ass. U.K., 53: 493-520.

 

Thorson, G. 1946. Reproduction and larval development of the Danish marine bottom invertebrates. Meddelelser fra Kommissionen for Danmarks Fiskeri- og Havundersøgelser, Serie Plankton 4: 1-523.

 

Wigham, G.D. & Graham, A. 2017. Marine gastropods 2: Littorinimorpha and other, unassigned, Caenogastropoda. Synopses of the British Fauna (New Series) no.61. (344 pages). Field Studies Council, Telford, England.

 

Glossary

‰ = (salinity) parts salt per thousand parts water (brackish <30‰).

abapertural = away from the aperture.

abapical = away from the apex of the shell.

adapertural = towards the aperture

adapical = towards the apex of the shell.

aperture = mouth of gastropod shell; outlet for head and foot.

apical = at or near the apex.

chink = (see columellar groove).

columella = solid or hollow axis around which gastropod shell spirals; concealed except next to aperture where hollow ones may end in an umbilicus, slit or siphonal canal.

 

columellar = (adj.) of or near central axis of spiral gastropod,

columellar groove = Groove where one face of hollow columella missing, terminates in umbilicus. Also called “lacuna” or “chink.

 

columellar lip = lower (abapical) part of inner lip of aperture.

cephalic = (adj.) of the head.

costa = (pl. costae) rib crossing a whorl of a gastropod shell at about 90° to direction of coiling and any spiral ribs or lines.

 

costal = (adj.) of, or arranged like, costae.

ctenidium = comb-like molluscan gill; usually an axis with a row of filaments either side.

height = (of gastropod shells) distance from apex of spire to base of aperture.

lacuna = (see columellar groove).

mantle = sheet of tissue that secretes the shell and forms a cavity for the gill.

oligogyrous = (of a spiral) having few turns.

operculum = plate of horny conchiolin used to close shell aperture.

palatal lip = outer lip of gastropod aperture.

parietal lip = upper (adapical) part of inner lip of gastropod aperture that lies, often as a glaze, on surface of whorl.

 

periostracum = thin horny layer of conchiolin often coating shells.

plankton = animals and plants that drift in pelagic zone (main body of water).

protoconch = apical whorls produced during embryonic and larval stages of gastropod; often different in form from other whorls.

 

suture = groove or line where whorls adjoin.

umbilicus = cavity up axis of some gastropods, open as a hole or chink on base of shell, sometimes sealed over.

 

umbilical groove = narrow slit opening of umbilicus on some gastropods.

veliger = shelled larva of marine gastropod or bivalve mollusc which swims by beating cilia of a velum (bilobed flap).

  

How to create an encrypted zip file on Linux

 

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Aarhus, Denmark – December 2024.

Another common form of mine locomotive was driven by compressed air. These had a large air reservoir which could be refilled from a stationary source.

Frobisher Crescent, Shakespeare and Lauderdale Towers on the Barbican Estate, City of London.

Test scene, exposure raised by two stops in Lightroom.

 

High-quality JPEG exported from a compressed RAW file.

 

See the full article on Analog Senses:

www.analogsenses.com/2015/11/18/first-impressions-on-the-...

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