Revision of Chondrocyclus s. l. (Mollusca: Cyclophoridae), with description of a new genus and twelve new species
Author
Cole, Mary L.
text
European Journal of Taxonomy
2019
2019-10-22
569
1
92
journal article
25155
10.5852/ejt.2019.569
ee4333ce-4fde-4a61-85e9-effa3d1b5999
3517522
79BE13FC-B840-4C39-8D25-3328BDCC44D2
Chondrocyclus pondoensis
sp. nov.
urn:lsid:zoobank.org:act:
3913F1CE-3CB5-4B2F-AA60-BB811D014A4B
Figs 10
G–H, 16A, 17
Diagnosis
Shell small, depressed, lenticular; protoconch not mammillate; periostracum with dense, erect, transverse costae, expanded to form five spiral rows of raised flanges: a paddle-shaped row at periphery, a row of well-developed quadrangularly-shaped flanges around umbilicus and above periphery and a row of lower semi-circular flanges below suture; operculum duplex, lamella forming outer portion of operculum step shaped and terminating in a long solid fringe, portion above fringe consists of a lattice-like network of interwoven bristles some fused to fringe, projecting well above fringe and sloping inward towards centre; umbilicus wide and deep, exposing all the whorls;
radula
with three large cusps on second lateral tooth, cusps of rachidian, first and second lateral teeth fairly uniform in size; penis flattened dorsoventrally and laterally expanded about midway down the shaft, intromittent organ relatively long.
Etymology
Named for the distribution of the species, centered around the Pondoland region.
Type material examined
Holotype
SOUTH
AFRICA
–
KwaZulu-Natal
•
Port Shepstone area
,
Marble Delta
,
Hlokohloko Valley
, middle section, riverine/scarp forest;
30.6619°
S
,
30.3342°
E
;
175 m
a.s.l.
;
Feb. 2012
;
J
. Harvey
leg.; in leaflitter;
NMSA
P
0643/
T
4160. (
Fig. 10
G–H)
Paratypes
SOUTH
AFRICA
–
KwaZulu-Natal
•
8 specimens
; same collection data as for holotype,
NMSA
W
8763/
T
4161
•
2 specimens
; same collection data as for preceding;
NHMUK
20160079
•
1 specimen
; same collection data as for preceding;
RMNH
.
MOL
.338286
•
8 specimens
;
Port Shepstone area
,
Marble Delta
,
Hlokohloko Valley
, middle section, riverine/scarp forest;
30.6608°
S
,
30.3325°
E
;
188 m
a.s.l.
; in leaf-litter,
Feb. 2012
;
J
. Harvey
leg.; in leaf-litter;
NMSA
W
8733/
T
4162
•
2 specimens
; same collection data as for preceding;
NMW
.
Z
.2016.003.00002
•
2 specimens
;
Port Shepstone area
,
Marble Delta
,
Hlokohloko Valley
, middle section, riverine/scarp forest;
30.6622°
S
,
30.3386°
E
;
145 m
a.s.l.
;
Feb. 2012
;
J
. Harvey
leg.; in leaf-litter;
NMSA
W
8765/
T
4171
•
1 specimen
; same collection data as for preceding;
RMNH
.
MOL
.338287
•
17 specimens
;
Port Shepstone
,
Simuma area
,
Hlokohloko valley
, riverine/scarp forest;
30.6631°
S
:
30.3368°
E
; ca
150–200 m
a.s.l.
;
5 Mar. 2011
;
Herbert
and
Davis
leg.; in leaf-litter;
NMSA
W
7844/
T
4144
•
7 specimens
;
Umtamvuna Nature Reserve
,
Port Edward
,
Old Pont Road
,
2.5 km
upstream of mouth;
31.0603°
S
,
30.1725°
E
;
56 m
a.s.l.
;
13 Apr. 2011
;
M
. Cole
,
D. Herbert
,
L
. Davies
and
R
. Daniels
leg.;
ELM
D16940/
T
113
•
5 specimens
; same collection data as for preceding;
ELM
W
03627/
T
114
•
2 specimens
; same collection data as for preceding;
NHMUK
20120271
. –
Eastern Cape
•
1 specimen
;
Mtentu
, north bank;
31.2400°
S
,
30.0367°
E
;
20 May 2005
;
M
. Bursey
and
V
. Ndibo
leg.;
ELM
W
03027/
T
109
•
2 specimens
;
Mtentu
, north bank,
1.5 km
upstream, inlet to first waterfall, on east side of inlet;
31.2389°
S
,
30.0340°
E
;
13 Jan. 2012
;
M
. Cole
leg.;
ELM
D17406/
T
110
•
1 specimen
; same collection data as for preceding;
ELM
W
03602/
T
111
•
1 specimen
;
Mtentu
, north bank,
3 km
upstream of mouth, inlet to second waterfall, west side of inlet;
31.2295°
S
,
30.0182°
E
;
43 m
a.s.l.
;
12 Jan. 2012
;
M
. Cole
leg.;
ELM
W
03603/
T
112
•
1 specimen
;
Mkambati Nature Reserve
, ‘
Superbowl’ forest
,
5 km
upstream of
Msikaba
mouth, east side of
Msikaba River
;
31.2978°
S
,
29.9293°
E
;
3 May 2004
;
M
. Bursey
leg.; in leaf-litter;
ELM
D14256/
T
107
•
2 specimens
; same collection data as for preceding;
18 May
2005
;
ELM
D15585/
T
108
•
1 specimen
;
Mbotyi
,
Drewes
camp, east of village, dune forest at east end of beach, just before cliffs;
31.4432°
S
,
29.7686°
E
;
13 Jan.
2003
;
M
Bursey
leg.;
ELM
D14396
/
T
106
•
1 specimen
;
Ntafufu
, below lodge, west bank,
2 km
upstream of mouth;
31.5514°
S
,
29.6175°
E
;
24 Apr.
2005
;
D.-
J
. Hodgkinson
leg.;
ELM
D15532/
T
101
•
2 specimens
;
Ntafufu
, east bank,
1.5 km
upstream of mouth;
31.5565°
S
,
29.6261°
E
;
24 Apr.
2005
;
M
. Bursey
leg.;
ELM
D15531/
T
102
•
2 specimens
;
Mpame forest
;
32.0856°
S
,
29.0306°
E
;
19 Feb.
2009
;
M
. Cole
leg.;
ELM
D16941/
T
105
•
2 specimens
;
Xora
,
Kumqolo Forest
, west bank of
Xora River
opposite mangrove swamp;
32.1589°
S
,
28.9848°
E
);
25 Oct.
2005
;
M
. Bursey
leg.;
ELM
D15537/
T
103
•
1 specimen
; same collection data as for preceding;
13 Aug.
2011
;
M
. Cole
leg.;
ELM
W
03663/
T
104
•
1 specimen
;
Manubi forest
;
32.4426°
S
,
28.6130°
E
;
3 Oct.
2017
;
M
. Cole
leg.;
ELM
W
04034/
T
203
.
Description
SHELL (
Fig. 17
A–C). Small, depressed, lenticular, adult diameter
4.59–6.18 mm
, height
2.42–3.42 mm
, diameter:height 1.59–2.00 (n = 19). Spire not much raised, protoconch not mammillate. Embryonic shell just over 1.5 whorls, microscopically malleate, junction between embryonic shell and teleoconch not particularly distinct, initially costae weak, becoming well developed after about a quarter of a whorl (
Fig. 17D
). 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. Periostracum glossy, honey-brown and lacquer-like with dense lamellate costae at regular intervals, approx. 154–184 (n = 14) on last whorl, expanded into five spiral rows of flanges: a paddle-shaped row at periphery, a row of well-developed quadrangularly-shaped flanges around umbilicus and above periphery and a row of lower semi-circular flanges below suture; flanges bear numerous axial riblets visible at very high magnification (
Fig. 17E
); intervals between costae with microscopic axial threads. Shell translucent, glossy, corneous yellowbrown when fresh.
LIVING ANIMAL. Creamy white with slight pigmentation on tentacles.
OPERCULUM (
Fig. 17
G–H). Duplex, outer portion consists of multispiral lamella with 4.5–5 whorls; lamellar blade high, stepped, long fringe emanates near top of vertical portion of blade; blade projects high above fringe and slopes inward towards centre, upper portion of lamellar blade consists of latticelike network of interwoven bristles, some bristles connected to main fringe so there is no groove between fringe and lamellar blade (
Fig. 17G
); at the growing edge the top portion of lamellar blade is more or less square, not sloping, becoming arrow shaped below fringe (
Fig. 17H
). Outer lamellar fringe reflexed over peristome preventing animal withdrawing into shell.
RADULA (
Fig. 17F
). Rachidian with five cusps, central one slightly longer; first and second laterals each with three large cusps, a smaller fourth and a vestigial fifth, cusps increase in size very slightly from central tooth outwards, but there is not a large difference in size between cusps.
PENIS (
Fig. 17
I–J). Expanded towards distal end, intromittent organ relatively long.
Distribution and habitat
Known primarily from near the coast between Xora in Transkei and Umtamvuna in southern Kwazulu- Natal, and also recorded inland in the Port Shepstone area (ca
200 m
a.s.l.) (
Fig. 16A
). (The Transkei is the area of the
Eastern Cape Province
between the Kei and Umtamvuna Rivers.)
Indigenous Scarp Forest of the Pondoland Gorge and Transkei Coastal Scarp subtypes (
von Maltitz
et al.
2003
), adjacent to rivers, in leaf litter. Scarp forests are a forest
type
occurring on south- and east-facing hills and gorges of the first plateau escarpment (
300–
1100
m
) and unique to the east of
South Africa
.
Remarks
Morphologically,
C. pondoensis
sp. nov.
resembles
C. trifimbriatus
in features of the periostracum, operculum and radula. The position of spiral rows of flanges is equivalent in
C. pondoensis
sp. nov.
and
C. trifimbriatus
specimens from the
type
locality. The radulae have teeth with cusps relatively uniform in size. The operculum of
C. pondoensis
sp. nov.
is flatter than that of coastal species of
Chondrocyclus
. However, it is distinguished from that of
C. trifimbriatus
by the outer lamellar blade projecting high above the fringe and sloping towards the centre and a well-developed lattice of interwoven bristles joining the lamellar blade to the fringe (
Fig. 17G
). Other species bearing a lattice of interwoven bristles at the top edge of lamellar blade, fused with the main fringe are the coastal
C.
putealis
Conolly, 1939
,
C.
bathrolophodes
Conolly, 1929
and
C. cooperae
sp. nov.
but these species have a relatively deep operculum.
In the molecular study,
C. pondoensis
sp. nov.
did not appear related to
C. trifimbriatus
or to any other lineages (
Cole
et al.
2019
).
In coastal areas of Transkei where
C. pondoensis
sp. nov.
is sympatric with
C. putealis
and
C. cooperae
sp. nov.
specimens appeared to be scarce and patchily distributed, while at localities in southern
KwaZulu-Natal
(Umtamvuna Nature Reserve and Hlokohloko valley inland of Port Shepstone) where
C. pondoensis
sp. nov.
was the only
Chondrocyclus
species recorded, specimens appeared to be common.