Eight new species of Gulella Pfeiffer, 1856 from the south-east coast of South Africa (Gastropoda: Streptaxidae)
Author
Cole, Mary L.
FDA80F4A-4E08-401E-8FF6-778E033BBBA7
East London Museum, 319 Oxford St, East London, 5201, South Africa and Department of Zoology and Entomology, Rhodes University, Makhanda, 6140, South Africa.
marybursey@elmuseum.za.org
Author
Herbert, David G.
0C09EE45-6198-482E-857A-EF690C2A016F
Department of Natural Sciences, National Museum Wales, Cardiff, United Kingdom and University of KwaZulu-Natal, P. Bag. X 01, Scottsville, 3209, South Africa.
phasianella@gmail.com
text
European Journal of Taxonomy
2022
2022-04-11
813
1
32
http://dx.doi.org/10.5852/ejt.2022.813.1729
journal article
56043
10.5852/ejt.2022.813.1729
ac406bb4-11b2-425e-b793-599560c503d9
2118-9773
6448751
687DE2C9-28A4-43E6-A47D-DE2D2839AB60
Gulella kenbrowni
sp. nov.
urn:lsid:zoobank.org:act:
A6355821-8B4F-4C8B-B6E8-9F01ECF2B66A
Figs 1A–D
,
2
Diagnosis
Shell minute, cylindrical; smooth and glossy; aperture sub-quadrate; apertural dentition seven-fold, including a parietal lamella, a large labral complex extending deeply into aperture with ridge-like upper and lower margins and hollow in centre, a low, inset transverse basal tooth to right of centre, a stronger inset basal tooth to left of centre and a large tricuspid columella lamella with two strong ridge-like teeth, and a smaller tooth below these; umbilicus widely open.
Etymology
Named for Kenneth Brown, long-standing member of the Conchological Society of
South Africa
, and with a particular interest in Streptaxoidea.
Material examined
Holotype
SOUTH AFRICA
–
Eastern Cape
•
Umtiza Nature Reserve
,
Tree Dassie Trail
,
East side of Buffalo Pass
;
33.0144° S
,
27.8081° E
;
21 Apr. 2006
;
M. Bursey
leg.;
NMSA
P1678/T4524, prev.
ELMD 14909
.
Paratypes
(listed from west to east)
SOUTHAFRICA
–
Eastern Cape
•
1spec.
;same collection data as for holotype;
NMW.Z.2021.011.00004
, prev.
ELMD 14909
•
1 spec.
; same collection data as for preceding;
8 Apr. 2002
;
M. Bursey
leg.;
NHMUK 20210065
, prev.
ELMD 13854
•
4 specs
.;
East London
;
33.00° S
,
27.93° E
;
J. Farquhar
collection; ELMD 13413/T 209, prev.
NMSA
E8144
•
2 specs
.; same collection data as for preceding;
NHMUK 20210066
, prev. ELMD 13413
•
2 specs
.;
Nxaxo Forest
,
secondary dune forest
;
32.5683°S
,
28.5416° E
;
19 Feb. 2008
;
M. Cole
leg.;
ELMD 15770/T 210
•
1 spec.
; same collection data as for preceding;
RMNH.MOL.452584
, prev.
ELMD 15770
•
1 spec.
;
Nxaxo
,
forest West of river mouth
;
32.5945° S
,
28.5158° E
;
21 Feb. 2008
;
M. Cole
leg.;
ELMD 15786/T 211
•
3 specs
.;
Ngqara
,
between Cebe and Mazeppa Bay
,
riverine forest
300 m
upstream of mouth
;
32.4902°S
,
28.6128° E
;
30 Mar. 2004
;
M. Bursey
leg.;
ELMD 13718/T 212
•
9 specs
.;
Mcelwana
,
between Cebe and Mazeppa Bay
,
dune forest on East bank of estuary
;
32.4985° S
,
28.6044°E
;
15 Apr. 2005
;
M. Bursey
leg.;
ELMD 15329/T 213
•
1 spec.
;
Dwesa Nature Reserve
,
dune forest West of Kobola estuary
;
32.3029°S
,
28.8365° E
;
1 Oct. 2017
;
M. Cole
leg.;
ELMD 18310/T 214
•
5 specs
.;
Cwebe Nature Reserve
,
East side of Mbashe River, vicinity of Mbhanyana Falls
;
32.2206° S
,
28.9079° E
;
4 Feb. 2004
;
M. Bursey
leg.;
ELMD 13889/T 215
•
2 specs
.; same collection data as for preceding;
NMW.Z.2021.011.00005
, prev. ELMD 13889
•
2 specs
.;
Cwebe Nature Reserve
,
East side of Mbashe River, vicinity of Mbhanyana Falls
;
32.2206°S
,
28.9079°E
;
26 Oct. 2004
;
M. Bursey
leg.;
RMNH.MOL.452582
, prev. ELMD 13889.
KwaZulu-Natal
•
6 specs
.;
Mtamvuna Gorge
,
Lourie Trail
,
riverine scarp forest
, stn 11-08;
31.0563° S
,
30.1689°E
;
40 m
a.s.l.
;
13 Apr. 2011
;
D. Herbert
,
L. Davis
, M. and
Cole, R. Daniels
leg.;
NMSA
W7906/T4480
•
2 specs
.; same locality as for preceding; ELMD 18751/T 216, prev.
NMSA
W7906
•
3 specs
.; same collection data as for preceding;
27 Dec. 2002
;
D. Herbert
leg.;
NMSA
W679/T4472
•
2 specs
.;
Ngele Forest
,
mist-belt Podocarpus forest
;
30.54°S
,
29.65°E
; ±
1350 m
a.s.l.
;
14 Nov. 1995
;
D. Herbert
and
L. Davis
leg.,
in leaf-litter sample
;
NMSA
V5186/T4476
•
12 specs
.;
Trafalgar area
,
Mpenjati Nature Reserve
,
Yengele Trail
,
dune forest
;
30.9691°S
,
30.2820°E
;
7 m
a.s.l.
;
28 Dec. 2002
;
D. Herbert
leg.;
NMSA
W379/T4474
•
1 spec.
; same collection data as for preceding; ELMD 18752/T 217, prev.
NMSA
W379
•
2 specs
.; same collection data as for preceding;
NHMUK 20210072
, prev.
NMSA
W379
•
2 specs
.; same collection data as for preceding;
NMW.Z.2021.012.00001
, prev.
NMSA
W379
•
2 specs
.; same collection data as for preceding;
RMNH.MOL.452583
, prev.
NMSA
W379
•
1 spec.
; same collection data as for preceding;
NMSA
W7443/T4475
•
3 specs
.;
Umdoni Nature Reserve
,
coastal forest
,
30.39° S
,
30.67° E
;
28 Oct. 2001
;
C. Symes
leg.;
NMSA
W857/T4482
.
Other material
(listed from west to east)
SOUTH AFRICA
–
Eastern Cape
•
2 specs
.; same collection data as for holotype;
ELMD 14909
•
1 spec.
; same collection data as for preceding;
8 Apr. 2002
;
M. Bursey
leg.;
ELMD 13854
•
2 specs
.;
East London Golf Club
,
dune forest
;
32.9986° S
,
27.9395° E
; ±
60 m
a.s.l.
;
3 Sep. 2007
;
M. Cole
leg.;
ELMD 15582
•
3 specs
.;
Ocean View Farm
,
Mpetu Hill
;
32.6481° S
,
28.0939° E
; ±
430 m
a.s.l.
;
3 Mar. 2005
;
M. Bursey
leg.;
ELMD 15308
KwaZulu-Natal
•
1 spec
.;
Mtamvuna Gorge
,
Lourie Trail
,
riverine scarp forest
, stn 11-08;
31.0563°S
,
30.1689° E
;
40 m
a.s.l.
;
13 Apr. 2011
;
D. Herbert
,
L. Davis
,
M. Cole
and
R. Daniels
leg.;
NMSA
P1611
, prev.
NMSA
W7906
•
2 specs
.;
Trafalgar area
,
Mpenjati Nature Reserve
,
Yengele Trail
,
dune forest
;
30.9691°S
,
30.2820° E
;
7 m
a.s.l.
;
19 Dec. 1997
;
K. Cradock
leg.;
NMSA
V6811
•
4 specs
.; same collection data as for preceding;
28 Dec. 2002
;
D. Herbert
leg.;
NMSA
P1609
, prev.
NMSA
W379
.
Description
SHELL (
Fig. 1
). Shell minute, cylindrical, length
1.9–2.4mm
, width 0.8–1.0 mm, L:W 2.0–2.5 (n = 25); smooth and glossy but with indistinct, microscopic growth lines. Protoconch approx.
0.8 mm
in diameter, comprising approx. 2.25 whorls, smooth; junction between protoconch and teleoconch not distinct. Teleoconch comprising approx. 3.5 whorls; first two whorls roundly convex, subsequent ones more weakly convex (
Fig. 1A–B
). Aperture sub-quadrate, rounded at base, markedly constricted by teeth; peristome thickened and reflected, broadly interrupted in parietal region; dentition seven-fold (
Fig. 1C
): 1) a strong parietal lamella, outer portion oblique and then curving inward so that the remainder runs into aperture more or less at right angles; outer portion fuses smoothly with outer lip; 2) a large labral slab extending deeply into aperture, with a sharp upper margin beginning with a cusp near lip edge defining lower part of labral sinus and running into aperture more or less parallel to parietal lamella, and a blunt ridge on its lower margin not reaching lip edge; 3) a low, deeply inset transverse basal tooth just to right of centre; 4) a less deeply inset, stronger, in-running, somewhat ridge-like, basal tooth to left of centre; 5–7) a large columella lamella with three teeth, middle and upper ones strong, with a shorter tooth below these at its base; middle tooth largest and ridge-like often curving downwards as it runs into aperture and appearing concave on its lower surface. Labral slab corresponds with a fairly shallow indentation behind outer lip (
Fig. 1B
). Umbilicus widely open, elongate-oval, with a deep indentation underlying columella lamella; umbilical margin with axial pleats, often irregular and rather indistinct (
Fig. 1D
). Shell almost transparent when fresh, orange-red or yellowish coloration of dried tissue of animal visible internally.
Distribution
(
Fig. 2
)
Recorded on the coast of the
Eastern Cape
from East London northwards and in southern KwaZulu- Natal, where it is also recorded inland in the Kokstad area (
1350 m
a.s.l.). The latter locality is somewhat unexpected since the species is usually collected in close proximity to the coast.
Habitat
Coastal forest, including several classification
types
: Southern Coastal Forest, Scarp Forest, Transkei Dune Forest, Indian Ocean Coastal Belt (
Mucina & Geldenhuys 2006
;
von Maltitz
et al
. 2003
) and Southern Mistbelt Forest (Ngele near Kokstad) (
Mucina & Geldenhuys 2006
); in leaf-litter and under logs.
Remarks
Gulella kenbrowni
sp. nov.
has been treated as
G. sylvia
(Melvill & Ponsonby, 1903) (
Herbert & Kilburn 2004
)
, although it was noted that Transkei and southern
KwaZulu-Natal
material might turn out to be a separate, unnamed species upon further study.
Gulella kenbrowni
sp. nov.
resembles
G. bomvana
Cole & Herbert, 2009
, which occupies a small area within the range of
G. kenbrowni
sp. nov.
, but the latter is larger, its basal tooth is further to the left of centre, and its umbilicus is widely open.
Gulella kenbrowni
sp. nov.
also closely resembles
G. fordycei
sp. nov.
described below; differences are discussed thereunder. The labral slab resembles that of
Gulella tietzae
Cole & Herbert, 2009
, but it is smaller than that of both
G. bomvana
and
G. tietzae
.
Conservation
Gulella kenbrowni
sp. nov.
occurs over a relatively wider range than the other species described in this paper and many other South African
Streptaxidae
(
Herbert & Kilburn 2004
;
Bursey & Herbert 2004
;
Cole & Herbert 2009
). There are several small nature reserves within its range, but uncontrolled human access and trampling by cattle are commonplace. Forests in this region remain habitats of conservation concern.