Chondrocyclus pulcherrimus, Cole, 2019

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: 39-42

publication ID

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

publication LSID

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

DOI

http://doi.org/10.5281/zenodo.5586681

persistent identifier

http://treatment.plazi.org/id/F19B8F07-075C-4A7F-BD19-BB875003E7D0

taxon LSID

lsid:zoobank.org:act:F19B8F07-075C-4A7F-BD19-BB875003E7D0

treatment provided by

Plazi

scientific name

Chondrocyclus pulcherrimus
status

sp. nov.

Chondrocyclus pulcherrimus   sp. nov.

urn:lsid:zoobank.org:act:

Figs 10 View Fig J–K, 16 A, 19

Diagnosis

Shell very small, very depressed, discoidal; periostracum with very dense axial costae developing at the periphery a row of quadrangularly-shaped flanges and several spiral rows of semicircular flanges above and below this; operculum duplex, exterior saucer-shaped portion with step-shaped multispiral lamella terminating in a long solid fringe reflexed over peristome; radula with three large cusps on second lateral tooth, cusps on rachidian uniform in size; penis flattened dorsoventrally and laterally expanded on left side from about midway down the shaft.

Etymology

The specific name is derived from the Latin ‘ pulcherrimus   ’, meaning ‘most beautiful’, with reference to the ornate periostracum with very dense axial lamellae and a larger number of spiral rows of flanges than any other species.

Type material examined

Holotype

SOUTH AFRICA – KwaZulu-Natal • Ngome Forest, west of Nongoma, Southern Mistbelt forest ; 27.8245° S, 31.4191° E; 1136 m a.s.l.; 19 Jan. 2010; M. and K. Cole leg.; in leaf litter; NMSA W 9272 View Materials / T 3075. ( Fig. 10 View Fig J–K) GoogleMaps  

Paratypes

SOUTH AFRICA – KwaZulu-Natal • 66 specimens; same collection data as for holotype; ELM D16939 View Materials / T 118 GoogleMaps   1 specimen; same collection data as for holotype; ELM W 3626 View Materials / T 119 GoogleMaps   5 specimens; same collection data as for holotype; NHMUK 20120281 View Materials GoogleMaps   3 specimens in ethanol; same collection data as for holotype; NMW. Z.2019.004.00009 GoogleMaps   2 dry specimens; same collection data as for holotype; NMW. Z.2019.004.00008 GoogleMaps   4 specimens; same collection data as for holotype; RMNH MOL.330504 GoogleMaps   11 specimens; Ngome Forest , mist-belt Podocarpus   forest; 27.8250° S, 31.4183° E; 1200 m a.s.l.; 2 Dec. 1998; Herbert, Seddon and Tattersfield leg.; in leaf-litter beneath T richocladus grandilflorus; NMSA V 7103 View Materials / T 4112 GoogleMaps   24 specimens; Ngome Forest , mist-belt Podocarpus   forest; 27.8250° S, 31.4833° E; 1100 m a.s.l.; 2 Dec. 1998; Herbert, Seddon and Tattersfield leg.; in leaf-litter; NMSA V 8530 View Materials / T 4113 GoogleMaps   .

Description

SHELL ( Fig. 19 View Fig A–C). Small, very depressed, discoidal, adult diameter 3.50–4.85 mm, height 1.38– 2.56 mm, diameter:height 1.87–2.54(n = 22). Spire almost flat with sometimes only protoconch projecting ( Fig. 19 A View Fig ), suture deeply impressed. Embryonic shell ( Fig. 19D View Fig ) just over two whorls, sculptured with pock marks, junction between embryonic shell and teleoconch not particularly distinct, with weak costae at first, becoming stronger. Teleoconch comprising two whorls, rapidly increasing, suture deeply impressed. Aperture circular, last whorl descending near aperture, peristome simple, continuous and free. Umbilicus very wide, exposing all the whorls ( Fig. 19 C View Fig ). Periostracum glossy, light yellowishbrown and lacquer-like, with very dense lamellate axial costae at regular intervals, approx. 300 on last whorl (300 and 340 in Fig. 19 B and A View Fig , respectively), developing at the periphery quarangularly-shaped flanges, their expanded distal ends fused to form a solid fringe ( Fig. 19 E View Fig ); above periphery are four–five spiral rows of flanges and six–seven rows below it spiraling into umbilicus, height of flanges forming spiral rows varies; row of flanges below suture forms a channel (see Fig. 19 B,D View Fig ); intervals between costae smooth. Shell pale, corneous and translucent when fresh.

OPERCULUM ( Fig. 19 View Fig G–I). Duplex, outer portion consists of multispiral lamella with about 4.5 whorls, each step-shaped; at the growing edge the top of lamellar blade slopes down at an angle then curves under the step formed by the previous whorl and is thinner and more or less perpendicular where it is attached to the disc; very long fringe of fused bristles emanates from near base of vertical portion of step and curves upwards and then outwards forming a deep furrow between fringe and lamellar blade, spanned by a few bristles; a very short solid horizontal fringe emanates just below main fringe; top edge of lamella projects above level of fringe; fringe of each whorl fused to lamella of following whorl; outermost lamellar fringe very long and reflexed over peristome.

RADULA ( Fig. 19 F View Fig ). Rachidian with five cusps of approx. equivalent length; first lateral tooth with three cusps of approx. equivalent length and a very small fourth; second lateral tooth with three cusps of approx. equivalent length and two vestigial outer cusps; teeth do not differ much in size.

PENIS ( Fig. 19 View Fig J–K). flattened dorsoventrally and laterally expanded on left side from about midway down the shaft, with numerous annular rugae, smooth distal end occupies about one quarter of shaft.

Distribution and habitat

Known only from Ngome Forest, KwaZulu-Natal. Indigenous Eastern Mistbelt Forest ( von Maltitz et al. 2003) with large trees, south-facing; in leaf-litter ( Fig. 16 A View Fig ).

Remarks

The very dense costae of the periostracum of C. pulcherrimus   sp. nov. and large number of spiral rows of flanges, as well as the flat spire, immediately distinguish this species from all other species of Chondrocyclus   .

Chondrocyclus pulcherrimus   sp. nov. resembles C. trifimbriatus   in features of the operculum, radula, penis and the rough texture of the protoconch. The operculum is similar to that of C. trifimbriatus   , but the fringe emanates from near the bottom of the vertical portion of the stepped lamellar blade forming a deep groove while in C. trifimbriatus   it emanates from near the top of the blade and there is a very shallow groove between the fringe and lamella.

The Ngome Forest is 3360 ha and much of the forest is protected in the Ntendeka Wilderness Area. Chondrocyclus pulcherrimus   sp. nov. is locally very common unlike C. trifimbriatus   which appears to be rare in all populations sampled.

F

Field Museum of Natural History, Botany Department

B

Botanischer Garten und Botanisches Museum Berlin-Dahlem, Zentraleinrichtung der Freien Universitaet

A

Harvard University - Arnold Arboretum

BB

Buffalo Bill Museum

E

Royal Botanic Garden Edinburgh

S

Department of Botany, Swedish Museum of Natural History

M

Botanische Staatssammlung M�nchen

K

Royal Botanic Gardens

NMSA

KwaZulu-Natal Museum

W

Naturhistorisches Museum Wien

T

Tavera, Department of Geology and Geophysics

ELM

East London Museum

NMW

Naturhistorisches Museum, Wien

Z

Universit�t Z�rich

RMNH

National Museum of Natural History, Naturalis

V

Royal British Columbia Museum - Herbarium

C

University of Copenhagen