Nanocochlea damperensis Ponder & Clark & Eberhard & Studdert 2005, n. sp.
Creators: name: Ponder, W. F.
name: Clark, S. A.
name: Eberhard, S.
name: Studdert, J. B.
Publisher: name: Zenodo
Year: 2005
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Littorinimorpha
Hydrobiidae
Nanocochlea
Nanocochlea damperensis

description: Nanocochlea damperensis n. sp.   
Figures 4D; 6K–M; 8G; 14E–G; 15G–H; 16D–F; 17G–K; 18B.  
 Type material   
Holotype: AMS C.439399, first crossing, Damper Ck, stn PBs­1A, 29 MAR 1994.  
Paratypes: AMS C.203685, same data, 20+ dry, 20+ wet; QVM, 9:20543 (5 wet); AMS C.439400, same data (1 dry figured paratype).  
 Other material examined (all AMS)   
 Damper Creek: C.203673, 10m outside Damper Cave, stn PBs­2A (22 dry, 20+ wet); C.201282, near New River Lagoon, E side, Limestone Ck, where track crosses creek, JW 49, 15 FEB 1988; 20+ dry, 20 wet; figured specimen from same lot, C.343820.   
 Bauhaus: C.303685, cave entrance.   
 Etymology Named after Damper Creek.   
 Description   
 Shell (Figs. 6K–M; 14E–G; 15G, H). Length up to 2.3 mm; conical (SW/SL 0.50–0.69, mean 0.61, n = 63); spire moderate to tall, convex in outline; last whorl evenly rounded; suture indented/impressed. Protoconch microsculpture of small shallow pits and pustules. Teleoconch up to 3.3 whorls in adult; umbilicus present only in juveniles; aperture oval to pear­shaped; moderate size, shorter than spire (AL/SL 0.37–0.47, mean 0.42, n = 63); outer lip, orthocline, weakly thickened in adult, straight to slightly convex, without reflection; notch usually present in posterior corner of aperture; outer lip orthocline to weakly opisthocline; inner lip thin and narrow, in partial contact or narrowly separated from parietal wall.   
Dimensions. See Table 12.  
 Operculum (Fig. 16D–F). Inner surface with or without white smear and, in some, 3– 5 weak ridges (reduced pegs).   
 Eyes. Slightly pigmented.   
 Pallial cavity (Fig. 8G). Ctenidium narrow; 12–13 very small filaments; osphradium between posterior end and middle of ctenidium; hypobranchial gland thick to moderately developed; renal organ extends forward ca. ½ into pallial cavity; pericardium more than ½ in pallial roof.   
 Radula (Fig. 17G–K). Central teeth: dorsal edge with moderate to deep indentation; 4–5 lateral cusps, median cusp narrow, sharply pointed, about twice as long as adjacent cusps. Lateral teeth: dorsal edge with shallow indentation; with 5–6 cusps on outer and 4– 6 on inner side; median cusp narrow, sharply pointed, less than, to about twice as long as, adjacent cusps; ratio of cutting edge to shaft about ¼; basal projection pointed. Marginal teeth: Inner with 20–27 cusps; outer with 20–26 cusps.   
 Stomach. Stomach with posterior chamber a little smaller than anterior chamber.   
 Male genital system. Testis of 1.0–1.25 whorls; oval to kidney­shaped; oval in section. Pallial vas deferens straight to slightly undulating at prostate; straight between prostate and penis and at base of penis. Penis (Fig. 4D) with weak swelling in mid­distal portion; distal end long, papilla­like; medial section parallel sided; of medium length; penial duct in medial section strongly undulating; base of penis moderately wide; with moderate folds; penial duct straight to undulating.   
 Female genital system (Fig. 18B). Ovary of 1.0 whorls; oviduct extends to posterior edge of bursa copulatrix or slightly less; joins bursal duct just in front of posterior pallial wall. Bursa copulatrix of medium size, not extending to posterior pallial wall; globular; with bursal duct arising from middle of anterior edge of bursa; straight. Seminal receptacle at middle of inner wall of bursa copulatrix; ovoid or pyriform. More than ½ of albumen gland in front of posterior pallial wall; capsule gland up to? length of albumen gland; oval to compressed oval in section; anterior end blunt; ventral channel with indistinct to distinct vestibule; genital opening overlapping anterior end of capsule gland.   
 Distribution and habitat   
Found in Damper Creek near the entrance to Damper Cave but was not found in samples from inside Damper Cave (in the same creek). A sample of mainly empty shells from seepages at the entrance of Bauhaus cave (Fig. 15G, H) is also attributed to this species and a single dead shell (AMS C. 203714) from inside Bauhaus (Persephone Pot) is presumably washed in from a surface seepage. Specimens from the lower end of Limestone Creek on the eastern side of New River Lagoon are also attributed to this species (see remarks). The site in this creek is approximately 1.7 km S of the lower end of Damper Ck, although about 3.5 km separate the two locations where the samples were collected.  
 Remarks   
 Nanocochlea damperensis differs from the other Nanocochlea described to date in its broadly pupiform shell shape. Specimens from Limestone Creek are almost identical to the type material, although have more ctenidial filaments (14–17), 5–6 lateral cusps on the central teeth and the pallial vas deferens undulates rather than being straight. Other anatomical differences are the seminal receptacle is ovoid, not globular, the capsule gland has a terminal opening in some specimens and most specimens lack a distinct white smear on the operculum. Given their close geographic proximity and overall similarity, these two populations are considered to be conspecific pending more detailed investigation.   
 The very weak (rudimentary) multiple pegs on the operculum of this species resemble those seen in P. conica and P. arthurclarkei and have not been observed in other taxa included in Nanocochlea.   
 The shell­shape of this species resembles that of some taxa included in Austropyrgus (see Clark et al. 2003). Members of that genus have distinct pegs on the operculum, lack an S­shaped rectum and have three or more basal cusps on the central teeth.
description: Published as part of Ponder, W. F., Clark, S. A., Eberhard, S. & Studdert, J. B., 2005, A radiation of hydrobiid snails in the caves and streams at Precipitous Bluff southwest Tasmania, Australia (Mollusca: Caenogastropoda: Rissooidea: Hydrobiidae s. l.),, pp. 1-66 in Zootaxa 1074 (1) on pages 47-49, DOI: 10.11646/zootaxa.1074.1.1, http://zenodo.org/record/5050779