Copelatus pulchellus (Klug, 1834)

Ranarilalatiana, Tolotra, Raveloson Ravaomanarivo, Lala Harivelo & Bergsten, Johannes, 2019, Taxonomic revision of the genus Copelatus of Madagascar (Coleoptera, Dytiscidae, Copelatinae): the non- erichsonii group species, ZooKeys 869, pp. 19-90 : 19

publication ID

https://dx.doi.org/10.3897/zookeys.869.33997

publication LSID

lsid:zoobank.org:pub:B7C88A64-C06E-4B67-A352-F2F9C8FB0D1C

persistent identifier

https://treatment.plazi.org/id/0149666E-E3E1-5D2F-A4E1-80FD888742E5

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scientific name

Copelatus pulchellus (Klug, 1834)
status

 

Copelatus pulchellus (Klug, 1834) Figs 5C View Figure 5 , 8D View Figure 8

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. Jönsson, | 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. Jönsson, 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 View Figure 8 ). 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 View Figure 5 ). 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 View Figure 8 ). 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; Hájek 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 View Figure 5 ). Parameres more narrowly triangular apically compared to those in C. marginipennis and C. mahajanga .

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. Hájek 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 View Figure 11 ). 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 View Figure 5 . 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 Hájek 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 Hájek 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 Régimbart 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.

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Dytiscidae

Genus

Copelatus