Paraganitus ellynnae
Scientific classification
Kingdom:
Animalia
Phylum:
Mollusca
Class:
Gastropoda
(unranked):
clade Heterobranchia
clade Euthyneura
clade Panpulmonata
clade Acochlidiacea
clade Microhedylacea[1]
Family:
Microhedylidae s.l. / Ganitidae
Genus:
Paraganitus

Challis, 1968[2]
Species:
P. ellynnae
Binomial name
Paraganitus ellynnae
Challis, 1968

Paraganitus ellynnae is a species of sea slug, an acochlidian, a shell-less marine gastropod mollusc in the family Microhedylidae.

Paraganitus ellynnae is the only species in the genus Paraganitus.[1]

Description

Paraganitus ellynnae is smaller than 5 mm and is externally symmetric.[1] It has no shell in adults, and no operculum in adults.[1] It has also no head shield and no posterior shield.[1] It is able to partially retract parts of its anterior body into a temporal visceral cavity.[1] The visceral sac is largely separated from the rest of the body.[1] The mantle is robust.[1] The visceral hump is conical.[1] The tail is short and pointed.[1] The foot is narrow, the anterior foot edge is rounded and it can crawl on the whole foot.[1] It has no mantle cavity.[1] It has elongated/pointed rhinophores.[1] Like all acochlidians, it has oral (= labial) tentacles.[1] Paraganitus ellynnae has long and slightly recurved oral tentacles.[1] Oral tentacle nerves have been present in all examined acochlidians to date, but those nerves were not examined in this species.[1]

Like all acochlidians, it lacks plicate gills.[1] The position of the anus is unknown.[1] It has no calcareous spicules, but it has integumental concrements.[1] It has no keel on the visceral hump.[1]

It has aggregations of precerebral ‘accessory ganglia’.[1] It has no eyes.[1] The presence or absence of Hancock's organ is unknown.[1] It has prepharyngeal CNS as is the case in all other acochlidians.[1]

Ecology

Paraganitus ellynnae is marine and is a mesopsammic species, in other words, these very small slugs live in the interstitial spaces of marine sands.[1]

References

  1. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Schrödl M. & Neusser T. P. (2010). "Towards a phylogeny and evolution of Acochlidia (Mollusca: Gastropoda: Opisthobranchia)". Zoological Journal of the Linnean Society 158: 124-154. doi:10.1111/j.1096-3642.2009.00544.x.
  2. ↑ Challis (1968). Trans. R. Soc. N. Z. (Zool.) 10: 193.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.