Varadia Bhosale & Raheem, 2021

Bhosale, Amrut R., Saadi, Ahmed J., Wade, Christopher M., Thackeray, Tejas U., Tamboli, Asif S., Kadam, Suhas K., Muley, Dipak V. & Raheem, Dinarzarde C., 2021, Varadia, a new helicarionoidean semi-slug genus from India’s Western Ghats (Stylommatophora: Helicarionoidea), European Journal of Taxonomy 757 (1), pp. 50-79 : 58

Varadia Bhosale & Raheem gen. nov.

urn:lsid:zoobank.org:act:BB363A8F-6796-4874-BBF3-6CE1A207A3C3

Type species

Varadia amboliensis Bhosale, Thackeray, Muley & Raheem gen. et sp. nov. (here designated).

Diagnosis

Only known large semi-slug species from the Western Ghats having broad shell lobes (covering nearly all of the dorsal shell surface when fully extended) and a depressed, discoid shell with a large body whorl. Shell thin, glossy golden brown, with 4–4½ rapidly increasing whorls and barely raised spire. Extensive, largely free penial sheath enclosing substantial part of male genitalia. When sheath is in situ and penis in relaxed state, male genitalia constitute a single elongate, irregularly-shaped mass, with all of penis and epiphallic caecum, most of epiphallus and part of flagellum enclosed by sheath; only vas deferens and most of flagellum is visible outside intact sheath. Penial sheath divisible into thick proximal part and thin distal part, with transition between these two parts occurring between distal penis and epiphallic caecum. With penial sheath removed, following evident: region extending from penis to epiphallic caecum long and cylindrical, with distinctive S-shaped bend in penis and associated band of muscle running along length of penis; proximal ¾ of epiphallus held in long, conspicuous loop; and penial retractor muscle with two branches, one inserting subterminally on epiphallic caecum and one inserting on apex of loop of epiphallus. Inner wall of penis divisible into three regions: proximal penis (one major and several minor longitudinal pilasters), mid-penis (several minor longitudinal pilasters) and distal penis (a few minor pilasters with associated regular transverse ridges in interspaces). Inner wall of epiphallic caecum shows one long major longitudinal pilaster, a large mass of reticulate ridges proximally and several minor longitudinal pilasters distally. Gametolytic gland elongated and long; gametolytic sac 3–3.5 times as long as gametolytic duct. Amatorial organ absent. Spermatophore consists of elongated, soft capsule and long tail-pipe, with U-shaped bend at capsule–tail-pipe junction and funnel-like opening at tip of tail-pipe; surface smooth apart from four ribs running obliquely along length of tail-pipe and short spines near end of tail-pipe.

Etymology

The new genus is named in honour of the herpetologist Dr Varad Giri, who has made a major contribution to the modern study and conservation of the Indian herpetofauna; masculine.