Lerniana Delicado & Hauffe 2022, GEN. NOV.
Creators: name: Delicado, Diana
name: Hauffe, Torsten
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Littorinimorpha
Hydrobiidae
Lerniana

description: LERNIANA GEN. NOV.
Z o o b a n k r e g i s t r a t i o n: z o o b a n k. org:act: AAB227D3-CBD8-4E8A-A001-4AA29A9B4256
Type species: Hydrobia tritonum Bourguignat, 1852 (also known as Semisalsa tritonum; Schütt, 1980).
Etymology: The genus name refers to the Greek name Λέρνη, Lerna, a spring region that was once a lake and today is home to a population of the type species; gender feminine.
Diagnosis: Shell ovate-conic; 4.0–4.5 whorls; aperture oval with a straight narrow outer lip; umbilicus narrow. Operculum corneous, yellowish, thin, pliable, oval, without peg, and paucispiral with submarginal nucleus. One pair of basal cusps on radular central tooth. Ctenidium well developed, with 10–13 gill filaments. Osphradium positioned opposite approximate middle of ctenidium. Stomach without gastric caecum. Bursa copulatrix medium sized, pyriform, pedunculated and lying against the anterior section of the albumen gland; unpigmented renal oviduct; two seminal receptacles; SR2 smaller than SR1 and arising at the renal oviduct loop. Prostate gland bean shaped, about twice as long as wide. Penis strap-like, simple or with one small, medial outgrowth on its left side. Nervous system slightly pigmented, moderately concentrated.
Remarks: Lerniana is distinguished here from Radomaniola according to its smaller shell with a shorter spire, smaller stomach, pyriform bursa copulatrix with a shorter duct (of globular shape and with a longer duct in Radomaniola), smaller SR2, strap-like penis [although sometimes also gradually tapering, see Falniowski etal. (2012: 29, fig.7G1, G5) and Georgiev (2013: 294, fig. 2.4)] with a small outgrowth on the left side (larger and gradually tapering with a more prominent outgrowth in Radomaniola) and a generally more concentrated dorsal nerve ring (RPG ratio <0.5 in Lerniana) (Supporting Information, Figs S3, S 7, S 9). Moreover, all phylogenetic analyses congruently depicted the three species assigned to this new genus (i.e. R. tritonum, R. feheri and R. seminula) as a well-supported clade outside Radomaniola (Fig. 2). Falsibelgrandiella Radoman, 1973 is remarkably different from Lerniana because it bears a tubular shell, distinct shape and size of the seminal receptacles, and a penis with a wider base (Radoman, 1983). Lerniana is more similar in shell shape to Turcorientalia Radoman, 1973 and Pseudorientalia Radoman, 1983 but differs from Graecorientalia Radoman, 1983 in having a larger and pyriform bursa copulatrix with a shorter duct, larger SR1 and narrower base of the penis; from Turcorientalia in terms of its smaller bursa copulatrix, larger seminal receptacles and longer and narrower penis; and from Pseudorientalia according to its narrower bursa copulatrix, larger seminal receptacles and narrower penis (Radoman, 1983).
description: Published as part of Delicado, Diana & Hauffe, Torsten, 2022, Shell features and anatomy of the springsnail genus Radomaniola (Caenogastropoda: Hydrobiidae) show a different pace and mode of evolution over five million years, pp. 393-441 in Zoological Journal of the Linnean Society 196 on page 433, DOI: 10.1093/zoolinnean/zlab121, http://zenodo.org/record/7035584