Fusobela parvioculata, Criscione & Hallan & Puillandre & Fedosov, 2021

Criscione, Francesco, Hallan, Anders, Puillandre, Nicolas & Fedosov, Alexander, 2021, Where the snails have no name: a molecular phylogeny of Raphitomidae (Neogastropoda: Conoidea) uncovers vast unexplored diversity in the deep seas of temperate southern and eastern Australia, Zoological Journal of the Linnean Society 191, pp. 961-1000 : 980

FUSOBELA PARVIOCULATA SP. NOV.

( FIGS 3B, 5F)

Z o o B a n k r e g i s t r a t i o n: u r n: l s i d: z o o b a n k. org:act: 54C64B09-3287-4A66-AA3E-AAB0F84BEFF1.

Holotype: Australia, Tasmania, Flat area south of Brians , 1414 m, IN2018_ V06 _169, (–44.239, 147.293), TMAG E59231 .

Distribution: Known only from the type locality.

Etymology: The epithet is composed of the Latin parvus, small, and oculatus, with eyes, referring to the reduced size of the eyes of this species.

Description

Shell ( Fig. 3B) (SL = 18.2, SW = 8.8) biconicalfusiform, thin-walled, semitranslucent. Protoconch multispiral, broadly conical, of 2.7 convex whorls, eroded. Protoconch–teleoconch transition clearly defined, broadly sinuate. Teleoconch of about 4.3 whorls with reddish coloration; columellar area dark reddish; suture moderately impressed. Whorls with moderately wide subsutural ramp, straight to slightly convex throughout teleoconch. Lower portion of whorl evenly convex. Teleoconch sculpture of dense collabral growth lines, extending from subsutural ramp to lower portion of whorl; spiral sculpture of cords, more prominent on periphery and with few weaker cords on subsutural ramp. Last adult whorl weakly convex below subsutural ramp, gently tapering into short siphonal canal. Aperture elongate, approximately half of shell length; outer lip thin, inner lip straight. Anal sinus moderately wide, shallow, U-shaped.

Anatomy (based on female): Osphradium large; distinct, large, black rectal gland. Cephalic tentacles closely set, thick, conical; eyes small, black. Muscular bulb large, venom gland long, convoluted, the majority situated ventral to oesophagus. Proboscis long, with folded walls. Radular sac large.

Radula ( Fig. 6F) of hypodermic type, straight to gently curved, tightly rolled, slender, cylindrical, attaining 285 µm in length; no distinct barb or blade; adapical opening elongate, approaching one-tenth of shaft length; base narrow, comparatively short; external texture medium coarse. Ligament long, broad.

Remarks

Fusobela parvioculata can be differentiated from other raphitomids by the following a combination of characters: a biconical-fusiform, reddish shell with short siphonal canal not clearly demarcated from the shell base; conical, broad cephalic tentacles and long, cylindrical hypodermic teeth with no distinct barbs or blades.

An additional juvenile specimen (AMS C.571736) is here treated as Fusobela cf. parvioculata , due to the identical sculpture of the teleoconch to that of the holotype and the close genetic relationship. Further study is required to determine whether they ought to be considered truly conspecific or if they represent a species complex.