Revision of the intertidal and semiterrestrial crab genera Chiromantes Gistel, 1848, and Pseudosesarma Serène & Soh, 1970 (Crustacea: Brachyura: Sesarmidae), using morphology and molecular phylogenetics, with the establishment of nine new genera and two new species
Author
Schubart, Christoph D.
Zoology & Evolution, University of Regensburg, 93040 Regensburg, Germany
christoph.schubart@ur.de
Author
Ng, Peter K. L.
Lee Kong Chian Natural History Museum, Faculty of Science, National University of Singapore, 2 Conservatory Drive, Singapore 117377, Republic of Singapore
peterng@nus.edu.sg
text
Raffles Bulletin of Zoology
2020
2020-12-23
68
891
994
journal article
55667
10.26107/RBZ-2020-0097
6cb155ce-8b9f-48ce-8e6c-b0dc00f8b1cc
2345-7600
5351295
815E4670-B063-4FD8-B31E-3AD89B3A7942
Cristarma eulimene
(De Man, in
Weber, 1897
)
(
Figs. 13E
,
14E
,
15C, D
,
18C
,
20A–H
,
43G
)
Sesarma
(
Sesarma
)
eulimene
De Man
, in
Weber, 1897: 157
, pl. 15 fig. 1.
Sesarma eulimene
–
Stebbing, 1910: 322
;
Fourmanoir, 1953: 90
.
Sesarma
(
Holometopus
)
eulimene
–
Tesch, 1917: 150
;
Crosnier, 1965: 51
, figs. 68, 69, 73, 77b, 85, 107, 108;
Guinot, 1967: 288
;
Serène, 1968: 107
.
Holometopus eulimine
(sic) –
Hartnoll, 1975: 308
, 311, 316.
Chiromantes eulimene
–
Naderloo & Schubart, 2009: 67
.
“
Chiromantes
”
eulimene
–
Ng et al., 2008a: 220
;
Emmerson, 2016: 235
, unnumbered colour fig.
Material examined
.
MOZAMBIQUE
–
1 male
(22.2 ×
17.2 mm
)
,
1 adult
female (15.6 ×
12.8 mm
) (
ZRC
1968.1.22.2– 3),
Inhaca Island
, coll.
W. McNae
,
April 1967
.
SOUTH AFRICA
–
2 males
(22.0 ×
17.8 mm
, 22.2 ×
18.5 mm
) (
ZRC 2017.0168
), mangrove creek,
Mngazana
,
Eastern Cape Province
, coll.
S. Cannici
,
9–10 March 2017
.
Diagnosis
. Carapace quadrate; lateral margin sinuous; dorsal margin of male cheliped dactylus with about 15 symmetrical tubercles on proximal half, followed by 10 asymmetrical tubercles on distal half; male pleon proportionately narrower, longer.
Colour
. In life, the species was described as with a brown carapace and red male chela (
Crosnier, 1965: 51
). In larger males, the centre of the chela becomes more faded (
Emmerson, 2016: 235
, unnumbered colour fig.).
Remarks
. The authorship for this species should be “De Man, in
Weber, 1897
”. Weber wrote the chapter on decapod crustaceans in his paper but noted that some contributions were by De Man (
Weber, 1897: 156
). In the new species description for
Sesarma eulimene
, it was clearly stated that the work was by De Man: “(Beschrieben von Herrn Dr. J. G. de Man.)” (
Weber, 1897: 157
). The year of publication is usually cited as 1898 but this is incorrect. While volume 10 of “Zoologische Jahrbücher, Abtheilung für Systematik, Geographie und Biologie der Thiere” was dated as 1898, the articles actually appeared in parts. Weber’s paper appeared in part 2 of volume 10, and this was stated to be published on
21 May 1897
. This species was described from
two males
and
four females
from Umbilo River in Natal (present day
KwaZulu-Natal
,
South Africa
), and he gave measurements for the
two males
(17 ×
14.25 mm
, 15 ×
12 mm
) and two larger females (15.3 ×
12.5 mm
, 12.25 ×
9.7 mm
). It is not known where this material is now and whether it is still extant; it is not in Leiden (
Fransen et al., 1997
).
Crosnier (1965: 51)
commented that he had compared his specimens to the
syntypes
but he did not elaborate if he had actually seen the specimens or based it on the publication only. In any case, the material reported by
Crosnier (1965)
from
Madagascar
and the present specimens agree well with De Man’s (1897) detailed description and good figures and we have no doubt of their conspecificity.
Crosnier (1965)
redescribed
C. eulimene
with good figures and compared it in detail with
C. ortmanni
. While both species have superficially a similar G1, their carapace shapes are quite different:
C. eulimene
is more squarish, with the lateral carapace margins sinuous (
Figs. 13E
,
20A
), while
C. ortmanni
is distinctly more transversely rectangular with the lateral margins almost straight (
Figs. 13F
,
20I
). In addition,
C. ortmanni
has 25 tubercles on the dorsal margin of the male cheliped dactylus, with half of them larger and relatively symmetrical (
Figs. 15E
,
20J
), while
C. eulimene
has only 12 slightly asymmetrical tubercles (
Figs. 15C
,
20D
). The male pleon of
C. ortmanni
is also slightly wider and shorter (
Figs. 18D
,
20K
) compared to that of
C. eulimene
(
Figs. 18C
,
20E
).
Biology
. The best account of the ecology of this species is by
Hartnoll (1975: 316)
who notes that it occurs only in the terrestrial vegetation above the supralittoral zone.
Neosarmatium africanum
Ragionieri, Fratini & Schubart, 2012
[as
N. meinerti
(
De Man, 1887
)
] and
C. ortmanni
also occur in this zone, with both species also found elsewhere in the mangroves.
Emmerson (2016: 237
, 238) provides a detailed summary of the known ecology and biology of the species.
Distribution
. From
Tanzania
and
Mozambique
to
South Africa
and
Madagascar
(
Crosnier, 1965: 51
;
Hartnoll, 1975
;
Emmerson, 2016
).