Chondrocyclus cooperae sp. nov.

urn:lsid:zoobank.org:act: 16788B3B-03BE-4452-B52C-83D7FE070A53

Figs 10 M–N, 16B, 24

Chondrocyclus putealis – Herbert & Kilburn 2004: 91 .

Diagnosis

Shell small, depressed, lenticular; periostracum with dense axial costae expanded into seven spiral rows of flanges on last whorl: one at periphery, and three each between periphery and suture and between periphery and umbilicus; costae and flanges bear numerous tiny vertical ridges; operculum duplex, exterior concave portion shaped like a wide cup or bowl, multispiral lamella with horizontal shelf of interwoven bristles spiralling up on inside of bowl, fused to a very long, loose fringe reflexed over peristome; radula with three large cusps on second lateral tooth; penis flattened dorsoventrally with prominent lateral expansion on left of shaft towards distal end, and with a characteristic long intromittent organ.

Etymology

Named for Janna Cooper, who helped collect specimens of this species and in recognition of her intimate knowledge of the Transkei coast.

Type material examined

Holotype SOUTH AFRICA – Eastern Cape • Umtiza Nature Reserve, east side of Buffalo Pass, indigenous scarp forest; 33.0144°S: 27.8081°E; 21 Apr. 2006; M. Bursey leg.; in leaf litter; NMSA W9271/T3074. (Fig. 10 M–N)

Paratypes SOUTH AFRICA – Eastern Cape • 2 specimens; same collection data as for holotype; ELM D14918/ T122 • 15 specimens; same collection data as for preceding; M. Cole leg., 18 Mar. 2011; ELM D16936/ T120 • 5 specimens; same collection data as for preceding; ELM W3623/T121 • 4 specimens; same collection data as for preceding; NHMUK 20120280 • 2 specimens; same collection data as for preceding; NMSA W9275/T3076 • 1 specimen; same collection data as for preceding; NMW.Z.2012.065.00009 • 3 specimens; same collection data as for preceding; RMNH MOL.330502 • 3 specimens; same collection data as for preceding; 20 May 2011; M. Cole leg.; ELM D17008/T123 • 4 specimens; Hickmans River, dune forest west of lagoon; 33.0700° S, 27.8364° E; 15 Mar. 2003; M. Bursey; ELM D16934/ T124 • 15 specimens; East London, Nahoon estuary east bank, 1 km upstream of mouth; 32.9804° S, 27.9433° E; 2 Jun. 2003; M. Bursey leg.; ELM D15533/T126 • 1 specimen; same collection data as for preceding; ELM W3681/T125 • 3 specimens; same collection data as for preceding; 8 Dec. 2009; M. Cole leg., ELM D16931/T127 • 11 specimens; same collection data as for preceding; ELM W03621/ T128 • 7 specimens; same collection data as for preceding; 30 Mar. 2011; M. Cole and D.-J. Hodgkinson leg., ELM W03622/T129 • 5 specimens; Gqunube Green, east bank of Gonubie River, 1 km upstream of mouth, forest on steep slope; 32.9329°S, 28.0235° E; 9 Apr. 2003; M. Bursey leg.; ELM W03028/ T130 • 5 specimens; Gqunube Green, Wilderness Valley, tributary of Gonubie River on east bank 2.5 km upstream of mouth; 32.9303° S, 28.0128° E; 11 Apr. 2002; M. Cole leg., ELM D17009/T131 • 4 specimens; Kwelera, Monrepos, Schultz Farm; 32.8883°S, 28.0417°E; 13 Nov. 2007; M. Cole leg., ELM D15603/T132 • 11 specimens; Viskop, east bank of Cefane River; 32.8047° S, 28.1319°E; 20 Nov. 2006; M. Bursey leg.; ELM D15121/T133 • 5 specimens; same collection data as for preceding; ELM W03112/T134 • 12 specimens; same collection data as for preceding; 30 Dec. 2009; M. Cole leg., ELM D16929/T135 • 1 specimen; same collection data as for preceding; ELM W03620/T136 • 3 specimens; Mazeppa Bay, east bank of Sihlontlweni estuary near mouth; 32.4783° S; 28.6460°E; 28 m a.s.l.; 23 Apr. 2015; M. Cole leg., ELM D17931/T137 • 3 specimens; same collection data as for preceding; ELM W03867/T138 • 1 specimen; Colleywobbles, south facing slope above vulture colony, sparse thicket invaded with Lantana; 31.9833°S, 28.5833° E; 20 Feb. 2006; M. Bursey leg.; ELM D14968/T139 • 1 specimen; Dwesa Nature Reserve, forest along roadside east of camp; 32.1528° S, 28.8417° E; 7 Mar. 2000; M. Bursey leg.; ELM W03212/T140; 5 specimens; same collection data as for preceding; 20 Feb. 2011; R. Daniels leg.; ELM D16935/T141 • 3 specimens; Xora, Nxeni Forest, east bank of Ntlonyane River; 32.1933° S, 28.9574°E; 8 Nov. 2012; M. and K. Cole leg., ELM D17499/ T142 • 13 specimens; same collection data as for preceding; ELM W03813/T143 • 2 specimens; Mpame forest; 32.0856°S, 29.0306°E; 20 Feb. 2009; M. Cole leg.; ELM D16937/T144 • 2 specimens; same collection data as for preceding; ELM W03624/T145 • 2 specimens; Hluleka Nature Reserve, forest on north bank of river, steeply sloping, after second bridge along forest road; 31.8196°S, 29.3155°E; 20 Apr. 2005; M. Bursey leg.; ELM D15529/T146 • 4 specimens; Port St. Johns, east bank of Umzimvubu River, 3 km upstream; 31.5972° S, 29.5350° E; 6 Jul. 2006; M. Bursey and V. Ndibo leg.; alive in leaflitter; ELM D15227/T147 • 3 specimens; Port St. Johns, travertine deposit area, 26 km upstream on Umzimvubu River; 31.5211°S, 29.4569° E; 22 Apr. 2005; M. Bursey and V. Ndibo leg.; ELM D15311/ T148 • 7 specimens; Mbotyi, forest near Mkozi River, south-facing forest on steep slope on east bank of Mkozi River; 31.4459°S, 29.7549°E; 2 Mar. 2003; M. Bursey leg.; ELM D14394/T149 • 1 specimen; same collection data as for preceding; ELM W2836/T150 .

Other material examined

SOUTH AFRICA – Eastern Cape • 1 specimen; Umtiza Nature Reserve, east side of Buffalo Pass, indigenous scarp forest; 33.0144° S, 27.8081° E; Nov. 1993; C.J. Vernon leg.; ELM D13141 • 32 spcimens; East London, Nahoon estuary east bank, 1 km upstream of mouth; 32.9804° S, 27.9433°E; 30 Mar. 2011; M. Cole and D.-J. Hodgkinson leg.; ELM D16932 • 1 specimen; East London, forest below casino, west bank of Nahoon River near Abbotsford causeway, 4.5 km upstream of mouth; 32.9692° S, 27.906000° E; 28 Jan. 2008; M. Cole leg.; ELM D16959 • 4 specimens; Gqunube Green, east bank of Gonubie River, 1 km upstream of mouth, forest on steep slope; 32.9329° S, 28.0235°E; 9 Apr. 2003; M. Bursey leg.; ELM D13644 • 1 specimen; Inkwenkwezi Private Game Reserve, inland of Cintsa; 32.8333°S, 28.0667°E; 22 Nov. 2006; M. Bursey leg.; ELM D15186 • 4 specimens; Viskop, east bank of Cefane River; 32.8047° S, 28.1319° E; 8 Apr. 2000; M. Bursey leg.; ELM D16930 • 2 specimens; same collection data as for preceding; 15 Jun. 2000; ELM D15536 • 3 specimens; Morgan’s Bay, Yellowood Park, 2 km upstream of mouth, riverine forest on south-west facing slope, predominantly Strelitzia nicolai; 32.6967°S, 28.3347° E; 14 Mar. 2005; M. Bursey leg.; ELM D15338 • 5 specimens; same collection data as for preceding; 6 Mar. 2011; R. Daniels leg.; ELM D16968 • 1 specimen; Dwesa Nature Reserve, forest along roadside east of camp; 32.1528°S, 28.8417° E; 5 Mar. 2000; M. Bursey leg.; ELM W03261 • 28 specimens; Xora, Nxeni Forest, east bank of Ntlonyane River; 32.1933° S, 28.9574° E; 11 Aug. 2011; M. Cole leg.; ELM D16938 • 7 specimens; same collection data as for preceding; ELM W03625 • 2 specimens; Sinangwana, Sigxeni Forest, east bank of Sinangwana River; 31.7474° S, 29.3708°E; 21 Apr. 2005; M. Bursey leg.; ELM D15427 • 3 specimens; Port St. Johns, east side of Umzimvubu River in valley north of Mount Sullivan; 31.5899° S, 29.5451°E; M. Bursey and V. Ndibo leg.; 6 Jul. 2006; alive in leaf-litter; ELM D15235 .

Description

SHELL (Fig. 24 A–C). Small, depressed, lenticular, adult diameter 4.51–6.51 mm, height 2.25–4.01 mm, diameter:height 1.44–2.32 (n = 66, measured in several populations throughout the range). Spire not much raised, apex almost flat (Fig. 24A). Embryonic shell (Fig. 23D) just under 1.75 whorls, microscopically malleate, roughest in centre, junction between embryonic shell and teleoconch evident with appearance of a few weak costae, but not sharply demarcated. Teleoconch comprising 2.75 whorls, moderately convex, rapidly increasing, suture deeply impressed. Aperture circular, last whorl descending strongly near aperture, peristome simple, continuous and free. Umbilicus wide and deep, exposing all the whorls (Fig. 24C). Periostracum glossy, honey-brown and lacquer-like with dense lamellate axial costae at regular intervals, density varying between populations, 105–179 (n = 27, counted in three separate populations), expanded into tall quadrangularly-shaped flanges at periphery, and six additional spiral rows of lowerstanding flanges on body whorl, three between suture and periphery and three rows between periphery and umbilicus, the row closest to umbilicus weaker than other rows (Fig. 24 A–C); flanges and portion of costae near umbilicus bear axial ridges visible at very high magnification (Fig. 24E); intervals between costae with microscopic axial threads. Shell translucent, glossy, honey-brown when fresh.

LIVING ANIMAL. Head, tentacles and snout dark grey, underside of foot creamy white.

OPERCULUM (Fig. 24 G–H).Duplex, outer multispiral portion with5.5 whorls forming a widely cupolaeform cup or bowl, upper edge of lamellar blade thickened, forming a horizontal shelf of interwoven bristles in a lattice-like pattern; in the outermost whorl the latter is continuous with a very long fringe reflexed over peristome and preventing operculum being withdrawn into shell; in earlier whorls this fringe is not visible and appears fused with the lamella; growing edge of lamella arrow shaped. Surface of lamella of last whorl tuberculate at high magnification.

RADULA (Fig. 24F). Rachidian with five cusps, central one approx. twice length of outer two on each side; first and second lateral teeth similar but second is larger, each with four cusps and a vestigial fifth; first three cusps gradually increasing in size from centre outwards and fourth very small.

PENIS (Fig. 24 I–J). Shaft dorsoventrally flattened, with large lateral expansion on left side, with numerous annular rugae, distal end smooth and not bulbous, intromittent organ very long.

Distribution and habitat

Endemic to Eastern Cape from East London to Mbotyi, primarily near the coast. The range of C. cooperae sp. nov. overlaps with that of C. bathrolophodes in the west, and C. pondoensis sp. nov. in the east (Fig. 16B).

Indigenous Scarp Forest (Mucina & Geldenhuys 2006) and Eastern Cape Dune Forest (von Maltitz et al. 2003), in leaf litter.

Remarks

Chondrocyclus cooperae sp. nov. resembles C. bathrolophodes and C. putealis in general shape, operculum and radula, but differs consistently in the larger number of spiral rows of periostracal flanges. The very long intromittent organ of the penis is unmistakable and immediately distinguishes the species.