Parmavitrina flavocarinata sp. nov.
Material examined. Holotype. AM C.512373 (Washpool National Park, off Gwydir Highway, NSW, 29° 29’ S, 152° 20’ E, 23/2/2016).
Paratypes. AM C.532841 (Same data as holotype).
Non-type material. See Table S1.
Description. Shell. Moderately large, 2.6 whorls, orange-amber, ear-shaped, flattened; last whorl large and flared with membraneous base; shell glossy, protoconch with fine spiral grooves, not closely spaced, and teleoconch with very fine, faint spiral grooves (Figs 22F, 23F).
Animal. Dark brown, spotted, yellow line along neck, foot border edged with crimson, slime network moderately strong, tail with a strong, yellow keel, caudal horn small. Mantle lobes moderately small, none fused, median lobe forms small cephalic shield; shell lappets broad, moderate in size, right lappet rounded, edged with black and with black markings (Fig. 24D).
Genitalia. Bursa copulatrix moderately long, approximately 1.5 times length of free oviduct. Penis short, appearing cylindrical when enclosed in penial tunica, penial tunica thick at distal end and thin at proximal end; penis swollen at proximal end; penis interior with longitudinal, zig-zagging pilasters, two present at distal end and numerous present at proximal end. Epiphallus short, less than 1.5 times penis length; enters penis through thickened ring. Epiphallic flagellum with spiraling rows of internal cryptae and slender tail. Spermatophore with spiraling rows of branching spines present on base of capsule with a few continuing on to tail-pipe; spines split into multiple branches aligned longitudinally (Fig. 31).
Remarks. Parmavitrina flavocarinata, preliminarily identified as ‘Helicarionidae sp. NN7’ through curatorial work, is known from the Gibraltar Range National Park to the Girard State Forest in northern NSW (Fig. 26), living under logs in rainforest habitats, and is the smallest Parmavitrina species. It is most similar to the sympatric P. megastoma but can be distinguished by its smaller size, darker colouration with small but distinct spots and lack of purple mucus. Its shell is darker in colour and has a less widely flared aperture. Anatomically it is distinguished by its proximally swollen penis with a penial tunica that is thick distally and thin proximally, zig-zagging pilasters and the lack of a penial verge.
Etymology. From flavus (Latin = yellow; adjective) and carinata (Latin = keeled; adjective), referring to the strong yellow keel.