Nigidius obesus Parry 1864: 63

Paulsen, M. J., 2018, Revision of the obesus species group of the stag beetle genus Nigidius MacLeay (Coleoptera: Lucanidae: Lucaninae: Figulini), Insecta Mundi 2018 (624), pp. 1-13 : 7

Nigidius obesus Parry 1864: 63

Type material. Lectotype, here designated, male ( NHM; Fig. 2 ) labeled: a) “85/28; yellow paper, handwritten “ obesus / Parry / Penang” ; b) “ BMNH (E) / 607172” . Paralectotype female ( NHM) labeled: a) red-bordered circular “Type”; b) “TYPE / SP. ” ; c) yellow paper, handwritten “ N. obesus . / Parry, Type / Westw. fig. 5 / Tr. Ent. Soc. 1874 / Cambodia ” ; d) yellow paper, handwritten “Type sp. vid / Tr. Ent. Soc. 73”; e) “85/28” ; f) “BMNH(E) / 607171” . Type locality: “ Penang, Malacca ”.

Additional material examined ( Fig. 14 ). MALAYSIA: PERAK: Batang Padang Jor Camp (1, NHM) ; Changkat Menteri (5, NHM) ; Perak (5, ZMHB) . PAHANG: Cameron Highlands (1, MJPC) .

Diagnosis. This species can be distinguished from the insular species by the narrower, more convex and less punctate elytral intervals, as well as by details of the male genitalia, which has a more sinuous flagellum with a different apex ( Fig. 10 ). It differs from N. dawnae in the medially impunctate elytral intervals and more oval (less lenticular) punctures laterally on the pronotum.

Remarks. The number of specimens examined by Parry (1864) is not indicated. The label 85/28 on both putative type specimens indicates accession into the NHM from the auction of specimens from the Parry collection via Mr. Janson. The lectotype male is appropriately labeled as being from Penang.The female has been labeled “ Cambodia ” in the same style, but this locality is not mentioned in the original description. A secondary label on the female specimen alludes to it being a type described in 1873. The species described by Parry (1873) from Cambodia is N. distinctus Parry , from a different species group with a drastically different form of ocular canthus. It is clear from the description of the emarginate lateral margin of the head with two distinct acute angles that the female in question is not N. obesus . Thus, the attribution of the species to Cambodia is considered erroneous.

Specimens studied were from March, October, and September. In general, adults of Nigidius species can be found year-round.

Figures

Figure 2. Nigidius obesus Parry, lectotype male, with labels (inset).

Figure 14. Distribution of obesus group species: N. obesus (triangles), N. dawnae (squares), N. gravelyi Paulsen, n. sp. (diamonds), N. helleri (circles).

Figures 10–13. Male genitalia of obesus group species. 10) N. obesus. 11) N. dawnae, arrow indicates small apical lobe. 12) N. gravelyi Paulsen, n. sp. 13) N. helleri, arrow indicates large lateral lobe.