Onthophagus (Indonthophagus) ensifer Boucomont, 1914

Ziani, Stefano, 2024, Historical and morphological review of the subgenus Indonthophagus Kabakov, 2006 of Onthophagus Latreille, 1802 (Coleoptera: Scarabaeidae: Scarabaeinae: Onthophagini), Insecta Mundi 2024 (38), pp. 1-42 : 7-10

Onthophagus (Indonthophagus) ensifer Boucomont, 1914

( Fig. 4 )

Onthophagus ensifer Boucomont 1914: 220 ; Boucomont and Gillet 1927: 136; Arrow 1931: 334; Petrovitz 1961: 102; Balthasar 1963: 342; Biswas and Chatterjee 1986a: 58; Biswas and Chatterjee 1986b: 88; Sewak 1986a: 138; Sewak 1986b: 14; Sewak and Yadva 1991: 26; Biswas and Mulay 2001: 140; Sewak 2003: 276; Sewak 2004: 118; Sewak 2005: 146; Shrestha 2005: 107; Krajcik 2006: 102; Rajan 2006: 124; Thomas et al. 2006: 5; Sewak 2006: 212; Vinod and Thomas 2006: 5; Thomas et al. 2007: 62; Sewak 2009a: 30; Sewak 2009b: 51; Sewak 2010: 108; Thomas et al. 2011: 33; Krajcik 2012: 178; Venugopal et al. 2012: 2687; Karimbumkara and Rajan 2013: 176; Krajcik 2013: 84; Rani and Sanjayan 2013: 242; Mittal and Jain 2015: 397; Sathiandran et al. 2015: 8254; Anu and Vinod 2017: 47; Latha and Thomas 2018a: 16123; Latha and Thomas 2018b: 1889; Latha 2019: 63; Sathiandran et al. 2021: 741; Asha et al. 2022: 7.

Onthophagus (incertae sedis) ensifer, Löbl et al. 2006: 174 ; Gupta et al. 2022: 426.

Onthophagus (Indonthophagus) ensifer, Kabakov 2006: 154 (footnote); Ziani and Bezděk 2016: 188; Gupta et al. 2018: 484; Kharel et al. 2020: 376; Schoolmeesters 2023.

Onthophagus (Onthophagus) ensifer, Sobhana et al. 2013: 95 .

Type locality. “Nilghiris: Coonour”; “ Madura distr. : Shembaganur” ; “Madras” [South India, Tamil Nadu state] .

Type material. Number of type specimens not specified in the original description, but more than one. One specimen, a major ♂, labelled as “type” and with a label handwritten by Boucomont himself, here considered a syntype, examined by photos ( MNHN).

Diagnostic features. Length 5.0 to 7.5 mm. Colour brownish black, elytra moderately shiny, with distinct isodiametric microreticulation, head and pronotum shinier, with cupreous or greenish metallic lustre, almost lacquered, not microreticulate. Antennal scape, pedicel and funicle dark red, antennal club brown. Dorsal pubescence whitish yellow.

Head short, clearly wider than long, with clypeus broadly round, slightly or not at all sinuate anteriorly, sides not sinuate; clypeofrontal carina distinct, sometimes barely discernible, bent backward, clearly closer to the base of the horn than to clypeal anterior margin in major males, extended in a slightly sinuate lamina, placed between the eyes, in the middle of them, in females; occipital carina extended in a long horn arising in correspondence of the anterior margin of eyes, broad and flat at base, directed backward, tapering gradually to the extremity and following the curvature of pronotum, often extending past the middle of the body, sometimes bifurcate apically, in major males, reduced to a narrow straight lamina in minor males and females; clypeal surface with transversely rugose, setigerous punctures, frontal surface doubly sparsely punctate.

Pronotum convex, declivous anteriorly, with a distinct anteromedian depressed smooth and unpunctured area and an anterolateral small tubercle on either side, a little behind the front margin, in major males, without depression and with an anteromedian transverse row, usually bilobate, besides the anterolateral tubercle, sometimes hardly appreciable, on either side, in minor males and females; both sexes with a small, hardly distinguishable, in some specimens almost undiscernible, posterolateral groove on either side near pronotal posterior angles;anterior angles distinctly produced, sides not sinuate behind them in dorsal view; dorsal surface setigerously punctate, punctures broad, sub-regular in distribution, separated by 1/2 to 1 diameter on disc, absent in the median depression, bearing pale-yellow setae, shorter on disc, barely longer at sides.

Elytral striae barely shiny, distinctly impressed, with punctures slightly larger than strial width and barely crenulating interstrial sides; interstriae convex, particularly the external ones, all rather regularly granulate; granules smaller than strial punctures; posterior margin of each granule with a small, indistinct, setigerous puncture; setae short, pale-yellow, thin.

Pygidium with rather regularly distributed, setigerous punctures; setae pale-yellow, thin, clearly longer that those of elytra.

Males with protibial spur directed outward, and with a small denticle strongly curved downward at the inner angle of protibial apex.

Male genital armature. Parameres short, apices bent ventrally, slightly diverging apically, without basolateral plate denticle, round at apex ( Fig. 4b–c ); endophallus with the presence of accessory endophallites, a single raspula and a U-shaped lamella copulatrix, frayed at one end, enlarged and bifurcate at the other ( Fig. 4d ).

Distribution. South India ( Boucomont 1914). Pakistan ( Petrovitz 1961). North India (Sewak 1986). Nepal ( Shrestha 2005).

Material examined. India: Tamil Nadu state, “Nilghiris / M. Maindron ”, “Coonour / 15-30 Juill. 1901 / 1500- 2000 m. alt.”, “ Boucomont det. 1914 / Onthophagus / ensifer n. sp. ♂ ”, “ Typus”, Muséum Paris / 1936 / Coll. A. Boucomont ”, examined by photos (syntype ♂ of O. ensifer, MNHN ) ; Tamil Nadu state, “Nilgiri Hills, 1922, H. L. Andrewes Bequest, compared with type. G. J. A[rrow]”, 2 ♂♂ and 1 ♀ ( MCSN) ; Tamil Nadu state, “Shembaganur” [Senbahanoor], 3 ♂♂ and 4 ♀♀ (Balthasar collection, NMPC) .

Historical review. Boucomont (1914) described O. ensifer on an unspecified number of specimens coming from three different localities, “Coonour”, “Shembaganur” and “Madras” whose present names are respectively Coonor, Senbahanoor and Chennai, all in the state of Tamil Nadu, South India. According the Article 73.2.3 of the Code ( ICZN 1999), the type locality of the taxon encompasses all these places.

Boucomont (1914) also stated that the new species could be a junior synonym of Onthophagus pardalis (Fabricius, 1798) , described, as Copris , from “ India ”. Unfortunately, always according to Boucomont (1914), Fabricius description was not sufficient for establishing the synonymy, and what’s more, the type of O. pardalis was lost.

Instead, Arrow (1931), citing Fabricius’ species, added an extensive description of both male and female and gave new records from central and southern India. He confirmed that pardalis ’ type had disappeared, but its original description appeared to him on the whole enough to apply to the concerned taxon. Therefore ( Arrow 1931) considered it bona species, not conspecific with O. ensifer .

Balthasar (1963), placed O. pardalis in the subgenus Colobonthophagus despite expressing the same considerations exposed by Arrow (1931), concerning its relationship with O. ensifer and O. mopsus .

Shortly after, Zimsen (1964) added a little twist to the story, reporting the existence of a specimen of O. pardalis type series, preserved in Kiel Museum ( Germany).

The existence of this specimen gave Scheuern (1996) the opportunity to provide another systematic interpretation of the issue. According to this author, the placement of O. pardalis by Balthasar (1963) was incorrect, as the species that Balthasar – and before him Arrow (1931) – called O. pardalis was not conspecific with Fabricius’ species nor with O. ensifer or O. mopsus . Scheuern (1996), after having designated the lectotype of O. pardalis , claimed not to be able to insert the species in any known subgenera of Onthophagus .

Despite this, Thomas et al. (2011), Karimbumkara and Rayan (2013), Mittal and Jain (2015), Karel et al. (2020) and Gupta et al. (2022) considered O. pardalis a Colobonthophagus , probably referring to the O. pardalis sensu Arrow and sensu Balthasar, that Scheuern (1996) named Onthophagus (Colobonthophagus) neocolobus Scheuern, 1996 . I could examine pictures of the lectotype of Onthophagus pardalis (Fabricius, 1798) , and can confirm its exclusion to the group treated in this paper, as already stated by Scheuern (1996).

Remarks. I was able to study specimens coming from Tamil Nadu state (southern India) only. The records listed in literature from northern India, Pakistan and Nepal are reasonable but anyway should be confirmed.

The morphology of the aedeagus, particularly of paramera ( Fig. 4b–c ), short and not elongate as in the other species treated here, casts some doubts on the placement of O. ensifer in the subgenus Indonthophagus . Nevertheless, for now I prefer to keep the species in this group, based on the shape of the lamella copulatrix that follows the pattern of the other species assigned to the subgenus.

Figures

Figure 4. Onthophagus (Indonthophagus) ensifer Boucomont, 1914 [major ♂: India, Tamil Nadu st.]. 4a) Dorsal habitus. 4b) Parameres, lateral view. 4c) Parameres, dorsal view. 4d) Endophallus. AcS: accessory endophallites. LC: lamella copulatrix. Rs: raspula. Photos by A. Degiovanni, edited by G. Fiumi.