Taxonomic revision of the genus Copelatus of Madagascar (Coleoptera, Dytiscidae, Copelatinae): the non- erichsonii group species
Author
Ranarilalatiana, Tolotra
Author
Raveloson Ravaomanarivo, Lala Harivelo
Author
Bergsten, Johannes
text
ZooKeys
2019
869
19
90
http://dx.doi.org/10.3897/zookeys.869.33997
journal article
http://dx.doi.org/10.3897/zookeys.869.33997
1313-2970-869-19
B7C88A64C06E4B67A352F2F9C8FB0D1C
C44C602AB0235FB2922DC2A4915C3288
Copelatus pulchellus (Klug, 1834)
Figs 5C
,
8D
Agabus pulchellus
Klug 1834
: t. XXXIII: 7
Copelatus africanus
Sharp, 1882: 583; TL: Botswana, Lake Ngami;
?
Copelatus basalis
Boheman, 1848: 244; TL: South Africa (Caffraria interiore);
Copelatus discoideus
Sharp, 1882: 582; TL: Mesopotamia;
Copelatus obtusus
Boheman, 1848: 242; TL: South Africa (Caffraria orientali);
Copelatus strigulosus
Sharp, 1882: 582; TL: Mesopotamia;
Copelatus mimetes
Guignot, 1957: 73; TL: Madagascar, Sakaraha, Lambomakandro; syn. nov.
Type locality.
Egypt, Sinai.
Type material studied.
-HT♂ (GP) (
Copelatus mimetes
) (MNHN, "coll. Guignot"): // Data in NHRS | JLKB | 000030032 // Sakaraha | Lambomakandro | III-56 A.R. // Type [red label] // F. Guignot Det., 1956 |
Copelatus
|
mimetes
n. sp.| Type ♂ // INSTITUT SCIENTIFIQUE MADAGASCAR // -LT♀ (lectotype here designated) (
Copelatus obtusus
) (NHRS): // Caffra | ria. // J. Wahlb // Type. // HoloTypus [red label,
"Typus"
printed,
"Holo"
handwritten with small letters in front, possibly by J. Balfour-Browne who studied the type] // obtusus Boh. //
Cop. pulchellus
var: |
obtusus
Boh. | J. Balfour-Browne det. // 5657 | E91 // NHRS-JLKB | 000065335 // Lectotype |
Copelatus obtusus
| Boheman, 1842 | Des. Ranarilalatiana | & Bergsten, 2019// -? ST♂ (
Copelatus basalis
) (NHRS): // Caffra | ria. // J Wahlb // Type. // Typus [red label, printed] // 158 | 61 // Copelatus | basalis Bhn. //
Copelatus
|
pulchellus
| Klug. | Det. 19.iv.1961 | J. Omer-Cooper. // 5597 | E91 // NHRS-JLKB | 000065337 // -? ST♀ (
Copelatus basalis
) (NHRS): // Caffra | ria. // J. Wahlb // Paratypus [red label, printed] // 160 | 61 // 5596 | E91 // NHRS-JLKB | 000065338 // -? ST♀ (
Copelatus basalis
) (NHRS): // Caffra | ria. // J. Wahlb // Paratypus [red label, printed] // 159 | 61 // 5595 | E91 // NHRS-JLKB | 000065339 //
Additional material studied.
Antsiranana. Diana: Antsiranana
: -1♂(GP) (MNHN): // Data in NHRS | JLKB | 000030259 // Madagascar | Diego-Suarez | Ch. Alluaud 1893 //
Mahajanga. Boeny: Mitsinjo
: -1♀ (NHRS): // NHRS-JLKB | 000065733 // Madagascar: Mahajanga: Boeny: | Mahavavy Kinkony RS: S 16.13337 | E 045.95778, 19 m.a.o. 04.XII.2009 | Water Net, Field# MAD09-25 | leg. J. Bergsten, N.
Joensson
, | T. Ranarilalatiana, H.J. Randriamihaja //
Mahajanga. Melaky: Antsalova
: -1♂(GP) (NHRS): // NHRS-JLKB | 000010695 // Madagascar: Mahajanga: Melaky: | Tsingy de Bemaraha NP: S19.03572 | E044.77507, 66 m.a.o. 15.XII.2009 | Water Net, Field# MAD09-58 | Leg. J. Bergsten, N.
Joensson
, T. | Ranarilalatiana, H.J. Randriamihaja //
Diagnosis.
Similar to
C. marginipennis
(Laporte, 1835) and
C. mahajanga
in overall habitus, but body shape more like the elongated shape of
C. mahajanga
.
Copelatus pulchellus
on Madagascar is ferrugineous black in overall colouration with or without a rather narrow or vague testaceous band basally on elytra (
Fig. 8D
). Instead testaceous regions on elytra are limited to posterolateral and apical parts. The first elytral stria almost full length. Penis in lateral view rather abruptly curved past middle so that basal and apical parts are approximately at right angles (
Fig. 5C
). Penis overall simpler compared to that of
C. marginipennis
and
C. mahajanga
and apex slightly twisted.
Description.
(based on Malagasy specimens):
Body length 5.5-6.1 mm. Body shape oblong oval, rather convex and attenuate posteriorly, dark brown to blackish ferrugineous. Head infuscated brown ferrugineous, somewhat lighter posteriorly, covered with dense microreticulation and sparser punctation.
Pronotum dark brown to ferrugineous black with testaceous anterolateral corners. Disc covered with fine microsculpture forming regular cells and regularily spread small punctures of about same size as cells. Punctuation becomes coarser in posterolateral corners with a weak tendency to corrugate.
Elytra predominantely dark brown to ferrugineous black on disc and along striae with or without a rather narrow and vague basal testaceous band (
Fig. 8D
). Outer intervals and apical region testaceous to varying degrees, often a testaceous interval 4 stands out. Elytral surface covered with same type of microsculpture and punctures as on pronotum. Six clearly impressed elytral striae present on disc and one submarginal stria: second to sixth stria starting at base, first stria somewhat abbreviated anteriorly (by approximately 1/8th the length of elytra); submarginal stria starting at approx. middle.
Ventral side ferrugineous dark brown, with testaceous spots laterally on abdominal ventrites. Metacoxa and ventrites with strioles. Prosternal process more elongate lanceolate and with blunter apex compared with
C. marginipennis
and
C. mahajanga
. Lateral parts of metaventrite medium broad. Metacoxal lines short and rather strongly diverging anteriorly. Antennae, palps, pro- and mesolegs testaceous, metalegs somewhat darker testaceous.
Female: elytral striolation limited to the medial parts of the outer three elytral intervals in the single female studied from Madagascar. From other parts of the distribution a female form is known that has the entire elytra striolated (
Sharp 1882
;
Hajek
and Reiter 2014
).
Male: protibia bisinuate and angled at base, distally expanded. Penis thin, strongly angled at middle in lateral view, and apex somewhat twisted to the left in ventral view (
Fig. 5C
). Parameres more narrowly triangular apically compared to those in
C. marginipennis
and
C. mahajanga
.
Figure 8. Habitus, dorsal view.
A
Male:
Copelatus marginipennis
B
Female:
Copelatus mahajanga
C
Female:
Copelatus
sp. 1 (Bemaraha)
D
Male:
Copelatus pulchellus
.
Distribution.
As the species
C. pulchellus
is currently interpreted, this is a very widely distributed Afrotropical and Middle Eastern species.
Balfour-Browne (1950)
recorded the species from Senegal in the west, Tanzania in the east, South Africa in the south, and Mesopotamia (Iraq and adjacent regions) in the Middle East.
Hajek
and Reiter (2014)
recorded the species from Yemen and stated that the likely distribution in the Middle East included the entire Arabian Peninsula.
Guignot (1961)
also gives India and Ceylon (= Sri Lanka) but this was likely based on the misidentification of closely related oriental species (see
Ghosh and Nilsson 2012
;
Sheth et al. 2018
).
Copelatus pulchellus
was not previously recorded from Madagascar following the revision by
Balfour-Browne (1950)
but as we synonymise
C. mimetes
with
C. pulchellus
, Madagascar now forms part of the distribution. From Madagascar we have seen specimens from Antsiranana, Mahavavy Kinkony Reserve, Tsingy de Bemaraha National Park (Bekopaka), and from Lambomakandro, Sakaraha (
Fig. 11C
). It can likely show up anywhere in lowland Madagascar, but especially in the western lowlands.
Habitat and ecology.
On Madagascar we have collected the species associated with a small forest stream with sidepools in a karstic limestone area (
"tsingy"
) and in a muddy stagnant pool in a dried-out river bed. Both localities are in dry deciduous forests of lowland western Madagascar.
Comment.
Copelatus pulchellus
forms part of a diverse species group with many externally very similar species.
Balfour-Browne (1950)
admitted that his previous treatment of the species (
Balfour-Browne 1939
) was entirely wrong as he had then not studied the male genitalia. When he did so in 1950 it resulted in the description of several new species previously lumped under
C. pulchellus
.
Copelatus pulchellus
is now interpreted as a widespread Afrotropical and Middle Eastern species with the male penis similar to that illustrated in
Figure 5C
. Dorsal colouration is interpreted as very variable, even consisting of several distinct colour forms such as the darker forms described as
C. obtusus
Boheman and later as
C. africanus
Sharp (compare figure 24 with photographs in
Perissinotto et al. (2016
: fig. 24) and
Hajek
and Reiter (2014
: fig. 30)). Females are also interpreted as variable in the striolation pattern on the elytra. Sharp described a female form from Mesopotamia that was entirely striolated over the elytra under the name
C. strigulosus
, which is interpreted today as intraspecific variation of
C. pulchellus
(see photograph in
Hajek
and Reiter (2014
: fig. 30)). We have seen three males and one female from Madagascar. All males are of the darker colour form, lacking a basal transverse testaceous band on elytra, similar to
Boheman's
C. obtusus
. The female has a weak basal testaceous band but is otherwise also most similar to the dark colour form. Striolation is limited to the middle of the outer three intervals. We have no doubt that the three non-type specimens examined are conspecific with
C. mimetes
Guignot. But after our comparison of the male genitalia of the type with
C. pulchellus
specimens from mainland Africa, we concluded that
C. mimetes
cannot be upheld as a separate species given how
C. pulchellus
is interpreted. We noted very minor differences in the penis apex which are not greater than differences between east, south, and west African specimens of
C. pulchellus
. The penis figured by
Guignot (1957
: fig. 2, reproduced by
Nilsson et al. 1997
: fig. 8) is very inaccurate, depicting a shape quite different from
C. pulchellus
but that does not correspond with the holotype.
Copelatus pulchellus
may still be a species complex for future studies to solve but currently it is a widespread and variable species distributed over Africa, Madagascar, and the Middle East.
Copelatus basalis
Boheman, 1848 was synonymised with
C. pulchellus
by Omer-Cooper (1965). We have studied the same type material as Omer-Cooper and agree with this conclusion. However, we are not convinced that the material housed at NHRS as these types are the correctly identified types of the name
C. basalis
.
Boheman (1848)
describes in Latin four species from Johan August Wahlbergs collectings in Caffraria (South Africa) of which three are new, numbered 259 -
Copelatus pulchellus
Klug; 260 -
Copelatus obtusus
; 261 -
Copelatus striatellus
; and 262 -
Copelatus basalis
. For
C. pulchellus
the disc of elytra is described as having six striae. For the longer description of
C. obtusus
this is further elaborated to detail that there are six discal stria but entire elytra has seven striae
"septem-striata"
(six discal and one submarginal). This pattern and number of striae is consistent with the
Copelatus pulchellus
species group. The following species is correctly identified as
C. striatellus
with nine discal striae, and is clearly stated as such: "disco striis 9 tenuibus", of which the innermost is much abbreviated. This description matches very well with the types preserved at NHRS. Finally,
C. basalis
is described as the last
Copelatus
species in
Boheman's
work and elytra is described as
"12-striata"
. The supposed types at NHRS for both
C. obtusus
and
C. basalis
have six discal and one submarginal striae. The type for
C. obtusus
matches the original description of
"septem-striata"
but the three types of
C. basalis
with the same number of striae does not match the original description of
"12-striata"
. It would be very inconsistent of Boheman to describe the total number of striae on one elytron in one case
"elytra...septem-striata"
, and in the other only the discal striae but summing up the number from both elytral halves
"elytra...12-striata"
. It would also be very illogical to place
C. basalis
after the 9-striated
C. striatellus
if it has the same number of striae as
C. pulchellus
and
C. obtusus
, which come first. Similarily,
Guignot (1961)
was confused about
Boheman's
C. basalis
and listed the name both under the 12-striated
C. mocquerysi
Regimbart
with a question mark, and under
C. pulchellus
. We consider the status of
C. basalis
Boheman as uncertain but we have not found any alternative potential type material at NHRS. We designate the single undoubted syntype of
C. obtusus
Boheman, 1848 in the NHRS collection as lectotype to preserve the stability of the name.