04 Rissoa parva
Non-costate interrupta specimens; shell thinner and more fragile than costate form; surface glossy and translucent.
Whorls less convex than on costate form; giving narrower ,sometimes almost straight-sided, profile.
1: rounded periphery of adult body-whorl,
2: angulated periphery of juvenile body-whorl.
3: whorls well defined by fine suture.
4: occasionally, single white line missing from cephalic tentacles of juveniles.
Brown lines on body-whorl vary greatly.
5: wide break at periphery in brown lines on body-whorl.
6: narrow break at periphery in brown lines on body-whorl; continuation of line off-set from first part.
7: brown lines stop at periphery; do not reach basal spiral line.
See image 2Rp for wavy lines.
8: yellow eye patch.
Shell heights 3 mm & 1.8 mm. Menai Strait, Wales. September 2011.
Full SPECIES DESCRIPTION: flic.kr/p/uxy617
Key id. features: flic.kr/p/uxFKZK
Sets of OTHER SPECIES:
www.flickr.com/photos/56388191@N08/collections/
04 Rissoa parva
Non-costate interrupta specimens; shell thinner and more fragile than costate form; surface glossy and translucent.
Whorls less convex than on costate form; giving narrower ,sometimes almost straight-sided, profile.
1: rounded periphery of adult body-whorl,
2: angulated periphery of juvenile body-whorl.
3: whorls well defined by fine suture.
4: occasionally, single white line missing from cephalic tentacles of juveniles.
Brown lines on body-whorl vary greatly.
5: wide break at periphery in brown lines on body-whorl.
6: narrow break at periphery in brown lines on body-whorl; continuation of line off-set from first part.
7: brown lines stop at periphery; do not reach basal spiral line.
See image 2Rp for wavy lines.
8: yellow eye patch.
Shell heights 3 mm & 1.8 mm. Menai Strait, Wales. September 2011.
Full SPECIES DESCRIPTION: flic.kr/p/uxy617
Key id. features: flic.kr/p/uxFKZK
Sets of OTHER SPECIES:
www.flickr.com/photos/56388191@N08/collections/