Validation of the South Asian cichlid genus Pseudetroplus Bleeker (Pisces: Cichlidae)
Author
Pethiyagoda, Rohan
Ichthyology Section, Australian Museum, 6 College Street, Sydney, NSW 2010. E-mail: rohanpet @ gmail. com.
Author
Maduwage, Kalana
School of Medicine and Public Health, University of Newcastle, NSW, Australia. E-mail: kalanapm @ gmail. com. & Department of Biochemistry, Faculty of Medicine, University of Peradeniya, Sri Lanka.
Author
Manamendra-Arachchi, Kelum
Postgraduate Institute of Archaeology, University of Kelaniya, 407 Bauddhaloka Mawatha, Colombo 7, Sri Lanka.
text
Zootaxa
2014
2014-07-22
3838
5
595
600
journal article
5427
10.11646/zootaxa.3838.5.9
2085bb99-6909-4375-bfea-e323f1225d10
1175-5326
4927701
4DBB159A-BFA8-48E5-94D0-D98C40099C39
Pseudetroplus
Bleeker
Pseudetroplus
Bleeker
, in
Günther, 1862: 266
;
type
species
Etroplus maculatus
(Bloch)
.
Pseudetroplus
Bleeker, 1862: 125
;
type
species
Etroplus coruchi
Cuvier.
Microgaster
Swainson, 1839: 171
(non
Latreille, 1804
).
Diagnosis.
Pseudetroplus
is distinguished from
Etroplus
by having 11 (vs. 12–13) pleural ribs; 26–27 (vs. 28–29) total vertebrae; lateral line incomplete (vs. interrupted), with 1–7 (vs. 13–24) pored scales; possessing an occipital prong (vs. possessing an occipital process;
Fig. 1D
); postero-dorsal outline of operculum curved, with a well-developed process (postero-dorsal outline of operculum straight, lacking a well-developed process); anterior half of median suture of lower pharyngeal jaw serrated (vs. smooth;
Fig. 1B
); base of the lateral arm of lower pharyngeal jaw broad (vs. narrow;
Fig. 1B
); first 6 anal-fin pterygiophores arranged anterior to the first 3 (vs. 2) haemal spines (
Fig. 1A
); supraoccipitalexoccipital prong well developed, extending ventrally over half-way across foramen magnum (vs. less-well developed, not extending into foramen magnum;
Fig. 1C
). Further, the anterior jaw teeth in
Pseudetroplus
are acuminate (vs. spatulate in
Etroplus
;
Fig. 2
).
Pseudetroplus
also differs from
Etroplus
in pigmentation, possessing one or more black blotches on the side of the body (vs. 7–9 prominent dark lateral bars in
Etroplus
); possessing two brown stripes on the dorsal fin (vs. lacking stripes on the dorsal fin); and lacking a black patch on the pectoral fin, near its base (vs. black blotch present on base of pectoral fin).
Discussion.
The name
Pseudetroplus
was published both by Bleeker in
Günther (1862)
and by
Bleeker (1862)
. While the date of publication of the former is
8 November 1862
(
Eschmeyer, 2014
), the date of publication of the latter is unknown and must under
ICZN (1999)
art. 21.3.2 be assumed to be 31 December, 1862.
Bleeker (1862)
gave the
type
species as
Etroplus coruchi
Cuvier, 1830
(
type
locality: Malabar [
Kerala
],
India
), a junior subjective synonym of
Chaetodon maculatus
Bloch, 1795
(
type
locality: ponds along the Coromandel coast [
Tamil Nadu
],
India
), while Bleeker in
Günther (1862)
specified the
type
species as
E. maculatus
.
The statement in
Eschmeyer (2014)
that "if [Bleeker in Günther] was first, then
suratensis
is probably the
type
" is evidently an error, for
Günther (1862: 266)
wrote: "According to a communication from Dr. v. Bleeker, he intends to separate this species [i.e.
E. suratensis
] generically from
E. maculatus
, retaining the name of
Etroplus
for the former, and adopting that of
Pseudetroplus
for the latter [i.e.
E. maculatus
]".
Cuvier (1830)
used the spelling
Etroplus coruchi
on p. 491 of his text, which indicated plate 136, on which he employed the name
Glyphisodon koruschi
:
as first reviser we here give precedence to the spelling
Etroplus coruchi
.
Microgaster
Swainson, 1839
(
type
species
E. coruchi
Cuvier
, in
Cuvier & Valenciennes, 1830
), while a senior synonym of
Pseudetroplus
, is a junior homonym of
Microgaster
Latreille (1804: 175)
in
Hymenoptera
.
FIGURE 1.
Osteology of
1
,
Pseudetroplus maculatus
, WHT
11087, 54.6 mm SL, Kerala, India;
2
,
Etroplus suratensis
, WHT
11088, 63.1 mm SL, Bellanwila, Sri Lanka;
3
,
E. canarensis
, WHT
11084, 48.3 mm SL, Natravedi River, Bengal, India.
A
, Anterior caudal vertebrae and associated structures in right lateral view;
B
, lower pharyngeal jaw;
C
, posterior view of neurocranium, showing foramen magnum;
D
, lateral view of supraoccipital crest and associated structures. Abbreviations:
Hsp.1
, first haemal spine;
Apt 1–2
, anal pterygiophore 1–2;
La
, lateral arm of lower pharyngeal jaw;
Ms
, median suture of lower pharyngeal jaw in lingual view;
Sec.pr
, supraoccipital-exoccipital prong;
Fm
, foramen magnum;
Soc.cr
, suproccipital crest;
occ.pg
, occipital prong;
occ.pr
, occipital process. Scale bar 1 mm.
FIGURE 2.
Anterior premaxillary dentition of A,
Pseudetroplus maculatus
, AMS B.
8099, 70.5 mm SL, Madras (Tamil Nadu), India; B,
Etroplus suratensis
, AMS I.
4478, 73.4 mm SL, Madras (Tamil Nadu), India; C,
E. canarensis
, AMS B.
8148, 61.5 mm SL, Canara (Karnataka), India.
Sparks (2008)
and
Stiassny
et al.
(2001)
distinguished the South Asian cichlids from their sister group, the Madagascan genus
Paretroplus
, by the former possessing more than a single row (vs. only a single row) of teeth in each jaw; the presence of a single lacrimal plate (lachrymal bifurcated in
Paretroplus
); and an asymmetrical displacement of the first anal-fin pterygiophore behind and the second in front of the haemal spine complex (vs. first anal-fin pterygiophore in front of and the second behind the haemal spine complex). While our results are consistent with this description, we note that the arrangement of anal-fin pterygiophores differs consistently between
Pseudetroplus
and
Etroplus
, with the former having the first 6 pterygiophores falling anterior to the first 3 haemal spines, whereas in the latter the first 6 pterygiophores fall anterior to the first 2 haemal spines: see
Fig. 1A
). Furthermore, whereas in both
Pseudetroplus
and
Etroplus
all lateral jaw teeth and the inner rows of the anterior teeth are tricuspid, the anterior jaw teeth are acuminate in adult
Pseudetroplus
and spatulate in adult
Etroplus
.
Sparks (2008)
noted also that the monophyly of the “
Etroplus suratensis
+
Etroplus canarensis
clade” (i.e.
Etroplus
sensu stricto
) was supported by the presence of a blunt snout with a steeply sloping profile in lateral view (particularly in specimens <about
75mm
SL); the presence of seven to nine prominent dark lateral bands; and an unique, unreversed character: a prominent black patch on the pectoral fin near its base. These, together with the dental and osteological characters mentioned in the Diagnosis, above, serve to distinguish
Pseudetroplus
from
Etroplus
.
Day (1877: 415)
noted that specimens of
P. maculatus
from Madras (the then presidency, now part of
Tamil Nadu State
, in which the
type
locality,
Tharangambadi
, is located) possessed 17–18 dorsal-fin and 11–12 anal-fin spines, whereas those in southern
Karnataka
possessed 19–20 and 14–15 spines, respectively. Should the populations of
Pseudetroplus
in the eastern and western regions of the Indian peninsula prove specifically different, the name
P. coruchi
Cuvier
, in
Cuvier & Valenciennes, 1830
, is available for the latter.
The difference in anterior jaw dentition in
Pseudetroplus
and
Etroplus
appears related to diet, the former being piscivorous, whereas adults of the latter feed on filamentous algae, detritus, aquatic plants and diatoms (
Bindu & Padmakumar, 2008
).