A. Wakefield 
Novapex 13(2): 69-74, 10 juin 2012 
A review of the Marginella bicatenata Sowerby, 1914 complex 
(Gastropoda: Marginellidae) with the description of a 
new southeast African Marginella species 
Andrew WAKEFIELD 
14 Forest Side, Buckhurst Hill, Essex, IG9 5SL, UK. 
bmw.awake@btintemet.com 
KEYWORDS. Marginellidae, South Africa, Marginella bicatenata , M. tomlini , M. lemaitrei, M. 
seccombei , species complexes, new species. 
ABSTRACT. The taxa Marginella bicatenata , Sowerby, 1914, M tomlini Shackleford, 1916 and 
M. lemaitrei Liltved & Millard, 1994, ail rare deep-water South African marginellids from off the 
southem Cape to KwaZulu-Natal, are revised from their type material and additional lots from 
both public and private collections. M. tomlini is proposed to be a junior synonym of M. 
bicatenata , whereas M. lemaitrei is considered to be a sibling species. Marginella seccombei n. 
sp., a benthic species from KwaZulu-Natal often confused with M. bicatenata on account of its 
superficially similar shell pattern, is described. 
INTRODUCTION 
In 1914, George Brettingham Sowerby (III) 
described a new species of Marginella from a then 
unique shell, lacking data, which had been discovered 
in the collection of a Mr. M. Denans. Since Denans 
had collected extensively in Sénégal, Sowerby 
erroneously assumed the type locality to be Gorée. 
The otherwise plain whitish shell was named 
Marginella bicatenata on account of its double row of 
dark spots, one at mid-body and the other at the 
shoulder. Two years later Lewis J. Shackleford, 
without reference to Sowerby’s taxon, described 
Marginella tomlini from a shell with a similar pattern, 
only this time its provenance was known with 
accuracy to be off Cape St. B laize, on the Southern 
Cape of South Africa. This shell was dredged from 
105 fathoms (équivalent to 192 m) indicating a deep 
water habitat on the Agulhas Bank. Since that time, 
and especially in recent years with increased sampling 
of South African benthic environments down to 
several hundred métrés and more, further specimens 
of shells resembling the type specimens of both taxa 
hâve corne to light and hâve found their way into both 
private and public collections. There has also been 
relatively recent taxonomie activity in this small 
complex of similar shells, with the description of 
Marginella lemaitrei Liltved & Millard, 1994. Despite 
the continuing scarcity of specimens available for 
study sufficient material now exists to make a 
preliminary review of the complex. 
M. bicatenata ranges from Africa’s southem Cape, 
northeast to central KwaZulu Natal, with the shells of 
this species exhibiting morphologie différences at 
each end of the géographie range of distribution. 
These différences are exemplified by the type 
specimens of M. bicatenata and M. tomlini. A new 
deep water species from Natal, bearing a superficially 
similar pattern of a double row of markings at the 
shoulder and mid-body, does not however appear to 
be directly related to M. bicatenata. It is described 
herein as M. seccombei n. sp. 
Materials and Methods 
Ail specimens from private collections and ail of the 
material of the new species described herein were 
obtained via suppliers who sourced material from 
South African commercial fishing vessels as dead 
dredged empty shells. Curators of national muséums 
in the United Kingdom and South Africa permitted the 
use of images and data of their examples of the 
species under study. Since live animais are as yet 
unknown, the species were treated conchologically. 
The author used a Nikon D300 SLR, a 60mm AF 
Micro Nikkor 1:2.8D lens and ring flash for images of 
M. bicatenata and M. seccombei n. sp. taken by the 
author. Images are shown at the same relative scale. 
Abbreviations 
NMW: Amgueddfu Cymru (National Muséum, 
Wales), Cardiff. 
NM: KwaZulu (Natal Muséum), Pietermaritzburg. 
SAM: Iziko (South African Muséum), Cape Town. 
AWC: Andrew Wakefield Collection, UK. 
TMC: Tony McCleery Collection, UK 
ad.: adult 
juv.: juvénile 
sh.: dead collected shell 
n. sp.: new species 
SYSTEMATICS 
Family MARGINELLIDAE Fleming, 1828 
Subfamily MARGINELLINAE Fleming, 1828 
Genus Marginella Lamarck, 1799 
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