Revision of Chondrocyclus s. l. (Mollusca: Cyclophoridae), with description of a new genus and twelve new species
Cole, Mary L.
European Journal of Taxonomy
2019
2019-10-22
569
1
92
7NSRK
Cole, 2019
Cole
2019
[590,773,1712,1739]
Gastropoda
Cyclophoridae
Chondrocyclus
GBIF
Animalia
Architaenioglossa
6
7
Mollusca
genus
stricto
Diagnosis Shell dextral, small (~ 4.5–6.5 mm), depressed, lenticular; aperture circular, last whorl descending near aperture, peristome not thickened, continuous and free; umbilicus wide and deep, exposing all the whorls; periostracum glossy and lacquer-like with lamellate axial costae at regular intervals, expanded into spiral rows of hairs or flanges; operculum duplex, corneous; inner portion consists of a thin disc which grows outwards in a tight spiral, smooth on inside where it attaches to foot; fused to disc on its outer surface is a multispiral, elevated horny blade-like lamella formed by fused bristles; height of lamella increases as it spirals outwards forming a concave exterior element; lamella not vertical, but stepped or flared, so that diameter of each whorl larger at proximal edge of lamellar blade; a fringe of fused bristles emanates from outer surface of each lamellar whorl; fringe reflexed over peristome but operculum can be withdrawn into aperture; radula taenioglossate; penis lies dorsally immediately behind right tentacle and consists of a stout, muscular shaft, cylindrical or dorsoventrally flattened and wrinkled along most of its length due to annular rugae, and a terminal, tapering intromittent organ without flagellum; seminal tube completely enclosed without seminal groove.
Key to species of Chondrocyclus 1. Periostracum bears spiral rows of hairs arising from axial lamellae ................................................. 2 – Axial lamellae of periostracum expanded into pointed or rounded flanges ...................................... 3 2. Distinct spiral grooves on shell corresponding to rows of periostracal hairs .... C. kevincolei sp. nov.– Spiral grooves weak if present................................................................... C. langebergensis sp. nov. 3. Protoconch mammillate and tilted ..................................................................................................... 4 – Protoconch not mammillate or tilted ................................................................................................. 8 4. Axial lamellae expanded into broadly rounded flanges at periphery; lamellae with numerous ridges perpendicular to shell surface ............................................................................. C. amathole sp. nov. – Periostracal flanges taper towards their proximal ends ..................................................................... 5 5. Flanges taper to rounded point .......................................................................................................... 6 – Flanges taper to acute tip ................................................................................................................... 7 6. Axial lamellae widely spaced; approx. 45 on body whorl.................................... C. herberti sp. nov.– Axial lamellae less widely space, approx. 70 on body whorl............................. C. silvicolus sp. nov. 7. Flanges taper from broad base into a long spine; second lateral tooth of radula with three large cusps; Western Cape................................................................................ C. convexiusculus( Pfeiffer, 1855) – Flanges taper gradually towards tips; if spine-tipped, spine short; second lateral tooth of radula with two large cusps; Eastern Cape................................................................ C. alabastris( Craven, 1880) 8. Operculum deeply or shallowly cup-shaped in side view ................................................................. 9 – Operculum more or less flattened in side view with outer portion parallel to disc surface and appears attached to disc by pedestal ..............................................................................................................11 9. Body whorl with at least six spiral rows of broadly rounded flanges.................. C. cooperae sp. nov.– Body whorl with three spiral rows of broadly rounded flanges....................................................... 10 10. Operculum deeply cup-shaped; southern Kwazulu-Nataland northern Transkei............................... .................................................................................................................. C. putealis Connolly, 1939 – Operculum cup-shaped; Albany area and southern Transkei ....... C. bathrolophodes Connolly, 1929 11. Operculum with spiral lamella of outer portion raised above level of fringe in side view; southern KwaZulu-Nataland Transkei........................................................................... C. pondoensis sp. nov. – Operculum with spiral lamella not raised above fringe................................................................... 12 12. Body whorl with only one row of broadly rounded flanges at periphery........... C. devilliersi sp. nov.– Body whorl with multiple spiral rows of rounded or paddle-shaped flanges .................................. 13 13. Body whorl with 12 spiral rows of flanges; spire almost flat ...................... C. pulcherrimus sp. nov.– Body whorl with five spiral rows of flanges..................................... C. trifimbriatus Connolly, 1929