Pleurobranchus varians
{{Short description|Species of gastropod}}
{{Speciesbox
| image =
| image_caption = Dorsal view of Pleurobranchus varians
| taxon = Pleurobranchus varians
| authority = Pease, 1860Pease W. H. (1860). "Descriptions of new species of Mollusca from the Sandwich Islands". Proceedings of the Zoological Society of London 28: 18–36. [https://archive.org/stream/lietuvostsrmoksl60liet#page/24/mode/2up page 25].
| synonyms =
}}
Pleurobranchus varians is a species of sea slug, a sidegill slug, a marine gastropod mollusc in the family Pleurobranchidae.
Taxonomy
The sister species (the closest relative) is Pleurobranchus areolatus from Caribbean.Goodheart J., Camacho-García Y., Padula V., Schrödl M., Cervera J. L., Gosliner T. M. & Valdés Á. (2015). "Systematics and biogeography of Pleurobranchus Cuvier, 1804, sea slugs (Heterobranchia: Nudipleura: Pleurobranchidae)". Zoological Journal of the Linnean Society 174(2): 322-362. {{doi|10.1111/zoj.12237}}. Those two species split 3.10 million years ago (Isthmus of Panama formed 3.1–3.4 Mya). Both species have color morphs and for their proper determination is useful the knowledge of locality.
Distribution
The distribution of P. varians include the Hawaiian Islands and Vanuatu. The type locality is Hawaiian Islands.
Description
P. varians was originally discovered and described by William Harper Pease in 1860. Pease' original text (the type description) reads as follow:
{{cquote|
Oval, rather rugose, convex above. Mantle rounded behind,
deeply sinuose in front, and margins slightly undulated. Tentacles arising from the head, curving laterally, deeply grooved below,
truncated, cylindrically tapering, transversely lamellated. Eyes at
their posterior bases. Oral veil large, convex in front, and much dilating laterally, where it is deeply grooved. Mouth proboscidiform.
Branchial plume simple, pinnate on the middle of the right side.
Foot large, reaching the edge of the mantle laterally and behind.
Colour varying; some bright red, others lemon-yellow, or purplish
brown, others again variegated with whitish; beneath paler than
above. Shell on the anterior half of the body, concealed, small, fragile, pellucid, oblong-ovate, convex, and ornamented with wrinkles of
growth. Nucleus posterior, more or less brownish.
}}