A new species and new records of deep-water Calappidae (Crustacea: Decapoda) from the Indian Ocean with a key to the Mursia Desmarest, 1823 species of the region
Author
Spiridonov, Vassily A.
Author
Apel, Michael
text
Journal of Natural History
2007
2007-12-31
41
45 - 48
2851
2890
http://dx.doi.org/10.1080/00222930701770786
journal article
10.1080/00222930701770786
1464-5262
5298150
Mursia africana
Galil, 1993
(
Figures 2A, B
,
3A, B
)
Mursia armata
:
Barnard 1950
, p 356
, Figure
67g
[not
Mursia armata
de Haan, 1837
].
Mursia africana
Galil 1993
, p 352
,
Figures 1a
,
2a, b
,
3a, b
.
?
Mursia africana
:
Ng et al. 2002
, p 356
–357.
Material examined
South-western Indian Ocean: off
Kenya
, 01
°
189–01
°
209N, 41
°
569–41
°
539E,
177–243 m
depth, trawl,
14–15 January 1965
,
RV
Meteor
, Cruise 1, St. 158:
one male
,
one juvenile
(
SMF
29497); off
Mozambique
,
15
°
05.09S
,
35
°
15.39E
, depth
210–230 m
, shrimp trawl,
RV
Vitiaz
,
Cruise
17,
St.
2635:
one male
(
IORAS
uncat.); off
Kenya
, 03
°
089S,
40
°
20.59E
– 03
°
079S, 40
°
219E, depth
250–255 m
,
5 September 1974
,
A. J. Bruce
coll.:
one male
(
holotype
, RMNH D 30986)
.
Type locality
Off
Kenya
, Western Indian Ocean.
Type material
See under ‘‘Material examined’’.
Size (
CL
×
MCW
)
Holotype
: 30.7×
56.6 mm
,
LS
59.1 mm
; specimen from off
Mozambique
: 30.4×
53.7 mm
,
LS
57.3 mm
.
Figure 2. Dorsal view of distal margin of cheliped merus. (A)
Mursia africana
, male, CL 30.4 mm (IORAS, unregistered), left cheliped; (B)
M. africana
, juvenile male, CL 14.7 mm (SMF 29497), left cheliped; (C)
Mursia
aff.
danigoi
, male, CL 52.5 mm (IORAS, unregistered), right cheliped; (D)
Mursia bicristimana
, male, CL 50.0 mm (ZMMU Ma 5353), right cheliped; (E)
M. bicristimana
, female, CL 37.0 mm (SMF 22942), right cheliped; (F)
Mursia flamma
, female, CL 46.3 mm (IORAS, unregistered), right cheliped; (G)
Mursia minuta
, male holotype, CL 17.1 mm (NHM 1907.5.22), right cheliped; (H)
M. minuta
, male, CL 19.5 mm (NHM 1898.8.26.3), right cheliped.
Figure 3. Gonopods 2 (Go/2). (A)
Mursia africana
, left Go/2, abdominal face, juvenile male, CL 14.7 mm (SMF 29497); (B)
M. africana
, left Go/2, abdominal face, CL 30.4 mm (IORAS, unregistered); (C)
Mursia bicristimana
, left Go/2, abdominal face, CL 50.0 mm (ZMMU Ma 5353); (D)
M. bicristimana
, left Go/2, terminal part, same specimen as in (C); (E)
Mursia
aff.
danigoi
, left Go/2, terminal part, abdominal face, CL 52.5 mm (IORAS, unregistered).
Habitat
Trawled at depth range
177–290 m
.
Distribution
Along East African coast from
Kenya
to
Mozambique
. A record from
Thailand
by
Ng et al. (2002)
is questionable, since especially the relative length of the lateral spine is a difficult character to distinguish between
M. africana
and similar species, such as
M. flamma
, and use of the key provided by
Galil (1993)
might lead to misidentifications (see ‘‘Remarks’’).
Remarks
The present specimens agree well with the description of
Galil (1993)
and the
holotype
deposited in the RMNH, which has been examined for comparison. Even though
M. africana
is similar to
M. flamma
Galil, 1993
, in particular regarding the shape of the Go/2 [compare
Figures 3a, b
and
10c, d
in
Galil (1993)
and our
Figure 3A, B
], the two species are distinguished by the following characters: carapace relatively wider and less convex in
M. africana
, lacking the additional tubercle between median and mesial branchial row of tubercles which is present in
M. flamma
; posterior margin of carapace with flattened, nearly effaced lobes in
M. africana
and three sharp teeth in
M. flamma
; the merus of the cheliped bispinose (but with a minute granular tubercle in addition to the two spines) in
M. africana
and trispinose in
M. flamma
. Contrary to the description provided by Galil, the median frontal lobe is more or less triangular in
M. africana
, while it is more rounded and bulbous in
M. flamma
.
The relative length of the lateral spines, a character often used for distinction of the species within the genus, however, is subject to considerable size-related variation. In
M. africana
the
LS
/
CW
ratio ranges from
0.35 in
small specimens to
0.20 in
larger size specimens, while in
M. flamma
it varies from 0.20 to 0.07. Thus, if this character is used for distinction of the two species the size of the actual specimen needs to be taken into account. Otherwise the use of this character might result in misidentifications.