Chondrocyclus bathrolophodes Connolly, 1929

Cole, Mary L., 2019, Revision of Chondrocyclus s. l. (Mollusca: Cyclophoridae), with description of a new genus and twelve new species, European Journal of Taxonomy 569, pp. 1-92 : 42-44

publication ID

https://doi.org/ 10.5852/ejt.2019.569

publication LSID

lsid:zoobank.org:pub:79BE13FC-B840-4C39-8D25-3328BDCC44D2

DOI

https://doi.org/10.5281/zenodo.5586683

persistent identifier

https://treatment.plazi.org/id/101687E3-D579-FFE5-FE06-AB44FC5BD189

treatment provided by

Plazi

scientific name

Chondrocyclus bathrolophodes Connolly, 1929
status

 

Chondrocyclus bathrolophodes Connolly, 1929 View in CoL

Figs 16B View Fig , 20–21 View Fig View Fig

Chondrocyclus bathrolophodes Connolly, 1929: 239 View in CoL , pl. xiv, figs 30–34 (type loc.: Kowie East [Kincaid]).

Chondrocyclus bathrolophodes – Connolly 1939: 538 View in CoL . — Herbert & Kilburn 2004: 92.

Diagnosis

Shell small, depressed, lenticular; periostracum with dense axial costae expanded into three spiral rows of flanges on last whorl: at periphery, around umbilicus and below suture; costae and flanges bear numerous tiny vertical ridges; operculum duplex, exterior portion with cup-shaped multispiral lamella with horizontal shelf of interwoven bristles spiralling up on inside of cup, fused to a very long, loose fringe reflexed over peristome; radula with three large cusps on second lateral tooth; penis flattened dorsoventrally with lateral expansions of shaft towards distal end, more prominent on left side.

Type material examined

Holotype

SOUTH AFRICA – Eastern Cape • Cape Province, Kowie East ; NHMUK 1928.3 View Materials .16.4. ( Fig. 20 A View Fig )

Other material examined

SOUTH AFRICA – Eastern Cape • 10 specimens; Port Elizabeth, Baakens River; 33.967° S, 25.333° E; Sep. 1998; ex Durban Museum; NMSA V 6683 • 28 specimens; Alexandria Forest, Langebos, vicinity of forest station; 33.6533° S, 26.4083° E; 2 Feb. 2009; M. Cole leg.; ELM D15950 • 7 specimens; same collection data as for preceding; top of ridge with beacon tower; 33.6951° S, 26.3542° E; 24 Nov. 2006; M. Bursey leg.; ELM D14938 View Materials • 1 specimen; same collection data as for preceding; 23 Nov. 2009; M. Cole leg.; ELM D16960 • 27 specimens; same collection data as for preceding; ELM W 03658 View Materials • 32 specimens; same collection data as for preceding; vicinity of hikers huts; 33.6991° S, 26.3636° E; 21 Nov. 2009; M. Cole leg.; ELM D16924 • 14 specimens; same collection data as for preceding; ELM W 03617 • 5 specimens in ethanol; same collection data as for preceding; NHMUK 20120274 • 5 specimens; Cannon Rocks, dune thicket; 33.7333° S, 26.5500° E; 2 Feb. 2009; M. Cole leg.; in leaf litter; ELM D16002 • 12 specimens; Port Alfred, coastal forest east of Kowie River mouth, dune forest behind tall dunes; 33.5919° S, 26.9047° E; 26 Nov. 2006; M. Bursey and T. Moffat leg.; in leaf litter; ELM D14998 • 50 specimens; same collection data as for preceding; 12 Oct. 2009; M. Cole leg.; ELM D16922 • 32 specimens; same collection data as for preceding; ELM W 03616 • 3 specimens in ethanol; same collection data as for preceding; NHMUK 20120273 • 2 specimens in ethanol; same collection data as for preceding; NMW. Z.2012.065.00005 • 66 specimens; same collection data as for preceding; 6 Apr. 2011; R. Daniels leg.; ELM D16923 • 12 specimens; Tharfield, east bank of Riet River, dune forest; 33.5589° S, 27.0150° E; 30 Jan. 2008; M. Cole leg.; ELM D15882 • 2 specimens; The Glen on Pig Island Farm on Kleinemonde River; 33.4833° S, 26.9333° E; 12 Jan. 2007; M. Bursey leg.; ELM W 03192 • 22 specimens; same collection data as for preceding; ELM D15394 • 25 specimens; same collection data as for preceding; 1 Feb. 2009; M. Cole leg.; ELM D16150 • 2 specimens; same collection data as for preceding; ELM W 03635 • 8 specimens; Kap River Nature Reserve, south bank, thin strip of forest at base of dry north-facing cliffs; 33.4821° S, 27.0758° E; 35 m a.s.l.; 21 Dec. 2002; M. Bursey leg.; ELM D16925 • 1 specimen; Kap River Nat. Res., north bank, in ravine; 33.4812° S, 27.0873° E; 42 m a.s.l.; 30 Dec. 2002; M. Bursey leg.; leaf litter; ELM D16926 • 3 specimens; same collection data as for preceding; 13 May 2011; M. Cole leg.; ELM D16927 • 6 specimens; same collection data as for preceding; ELM W 03618 • 32 specimens; Gess farm, indigenous forest in north-facing ravine leading into Kap river; 33.4803° S, 27.0634° E; 31 m a.s.l.; 28 May 2011; M. Cole leg.; ELM D16928 • 24 specimens; same collection data as for preceding; ELM W 03619 • 84 specimens; Kap River, north bank, indigenous riverine forest on shady, south-facing slope; 33.4830° S, 27.0807° E; 9 Jun. 2012; M Cole leg.; ELM D17002 • 1 specimen; Kei River, tributary on west bank 6 km upstream of mouth, forest on steep slope, south facing; 32.6300° S, 28.3483° E; 11 Feb. 2006; M. Bursey leg.; ELM D14990 • 7 specimens; Umthombe Kei Resort, west bank of Kei River, 6 km upstream of mouth, watercourse with steep banks, rocky in places; 32.6313° S, 28.3469° E; 42 m a.s.l.; 7 May 2018; M. Cole leg.; ELM D18355 • 10 specimens; same collection data as for preceding; ELM W 04053 • 1 specimen; Qolora estuary, west bank, steep slope with Strelitzia nicolai ; 32.6333° S, 28.4277° E; 14 m a.s.l.; 4 May 2006; D.- J. Hodgkinson leg.; ELM D14853 • 6 specimens; same collection data as for preceding; 11 Jun. 2018; M. Cole leg.; ELM W 04071 • 5 specimens; Kobonqaba, coastal forest on east side of mouth; 32.6058° S, 28.4933° E; 17 m a.s.l.; 23 Apr. 2015; M. Cole leg.; ELM D17932 • 3 specimens; same collection data as for preceding; ELM W 03868.

Description

SHELL ( Fig. 20 View Fig A–D). Small, depressed, lenticular, adult diameter 5.32–6.16 mm, height 2.76–3.45 mm, diameter:height 1.73–2.00 (n = 25). Spire depressed, each whorl just rising above the next, apex almost flat ( Fig. 20 View Fig A–B). Embryonic shell ( Fig. 21A View Fig ) 1.75 whorls, microscopically malleate, roughest in centre, junction between embryonic shell and teleoconch evident with appearance of a few weak axial costae, but not sharply demarcated. Teleoconch comprising 2.75 whorls, moderately convex, rapidly increasing, suture deeply impressed. Aperture circular, last whorl descending near aperture, peristome simple, continuous and free. Umbilicus wide and deep, exposing all the whorls ( Fig. 20D View Fig ). Periostracum glossy, honey-brown and lacquer-like with dense lamellate costae at regular intervals, 92–127 (n = 24) on last whorl, expanded into quadrangularly-shaped flanges at periphery, forming a distinct peripheral cord, as well as a row of shorter semicircular flanges below the suture and around the umbilicus ( Fig. 20 View Fig A–D); flanges bear numerous axial riblets visible at very high magnification ( Fig. 21B View Fig ); intervals between costae with microscopic axial threads ( Fig. 20B View Fig ). Shell translucent honey-brown when fresh.

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

OPERCULUM ( Fig. 21 View Fig C–E). Duplex, outer multispiral portion with 5.5 whorls forming a strongly concave cup, upper edge of lamellar blade thickened, forming a horizontal shelf of interwoven bristles spiralling up the inside of the cup; in the outermost whorl the latter is loosely connected to 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; surface of lamella of last whorl tuberculate at high magnification.

RADULA ( Fig. 21F View Fig ). Rachidian with five cusps, central cusp 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. 21 View Fig G–H). Shaft dorsoventrally flattened, with lateral expansions of shaft on both sides towards distal end but more prominent on left, with numerous annular rugae, distal end bulbous and smooth, intromittent organ exserted, but not elongated.

Distribution and habitat

Endemic to Eastern Cape coast with a disjunct distribution, occurring between Port Elizabeth and Great Fish River (recorded up to 9 km inland) and between Great Kei and Kobonqaba River (recorded up to 6 km inland) ( Fig. 16B View Fig ).

Albany Dune Strandveld on coastal dunes at Port Alfred (Mucina et al. 2006), Alexandria Forest with large trees, classified as Southern Coastal Forest ( Mucina & Geldenhuys 2006) or Albany Coastal Forest ( von Maltitz et al. 2003), Albany Thicket (Kowie Thicket and Buffels Thicket) ( Hoare et al. 2006) and Eastern Cape Dune Forest ( von Maltitz et al. 2003); in leaf-litter.

Remarks

Chondrocyclus bathrolophodes is similar to C. putealis (differences are discussed under the latter species) in periostracal ornamentation, operculum, radula and penis.

Specimens recorded in the vicinity of the Kei and Kobonqaba Rivers would have been difficult to identify on morphological grounds alone, but the molecular phylogeny shows unambiguously that the specimens sequenced are C. bathrolophodes ( Fig. 1 View Fig ). The species was previously thought to occur only in the Port Elizabeth–Albany area, but is shown to have a disjunct distribution. In very close proximity to Kobonqaba to the east, in the Nxaxo forest, Chondrocyclus specimens are morphologically very similar to C. bathrolophodes and C. putealis , but are neither of these species on molecular grounds ( Cole et al. 2019; Fig. 1 View Fig ). Chondrocyclus bathrolophodes exhibits very little genetic diversity at the end of a relatively long branch, suggesting recent geographical expansion and severe pruning of ancestral diversity by extinctions. All the coastal taxa of the Eastern clade show complex distribution patterns of sympatry, disjunctions and turnover within sharp contact zones. These could be the result of dynamic changes in vegetation over time, with forest contraction and expansion due to climatic oscillations ( Partridge 1993; Partridge et al. 1999). These processes could have caused repeated periods of isolation of populations in shrinking refuges, followed by dispersal and contact.

A

Harvard University - Arnold Arboretum

S

Department of Botany, Swedish Museum of Natural History

E

Royal Botanic Garden Edinburgh

NMSA

KwaZulu-Natal Museum

V

Royal British Columbia Museum - Herbarium

M

Botanische Staatssammlung M�nchen

ELM

East London Museum

W

Naturhistorisches Museum Wien

NHMUK

Natural History Museum, London

T

Tavera, Department of Geology and Geophysics

NMW

Naturhistorisches Museum, Wien

Z

Universit�t Z�rich

R

Departamento de Geologia, Universidad de Chile

J

University of the Witwatersrand

Kingdom

Animalia

Phylum

Mollusca

Class

Gastropoda

Order

Architaenioglossa

Family

Cyclophoridae

Genus

Chondrocyclus

Loc

Chondrocyclus bathrolophodes Connolly, 1929

Cole, Mary L. 2019
2019
Loc

Chondrocyclus bathrolophodes – Connolly 1939: 538

Herbert D. & Kilburn D. 2004: 92
Connolly M. 1939: 538
1939
Loc

Chondrocyclus bathrolophodes

Connolly M. 1929: 239
1929
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