Diatrichalus mindikensis, Bocek, Matej, 2017

Bocek, Matej, 2017, New species of Diatrichalus (Coleoptera: Lycidae) from New Guinea and the Moluccas, Zootaxa 4247 (5), pp. 577-584 : 582

Diatrichalus mindikensis sp. n.

( Figs 4 , 11–12 )

Type material. Holotype, male, Papua New Guinea, Mindik , 1500–1650 m, 06° 27´S 147° 25´E (A0184; LMBC).

Diagnosis. D. mindikensis sp. n. resembles externally other Diatrichalus species with the black body and blue metallic shine of elytra (i.e. D. aeneus Bocak , D. cyanescens Bourgeois , D. dilatatus Bocak , D. metallicus Kleine ; Bocak 2001), but differs in the extremely robust phallus ( Figs 11–12 ) and very small male eyes.

Description. Male. Body medium-sized, slightly widened posteriorly; black colored, only elytra dark brown to black; head, pronotum, elytra, antennomere 1 and also femora with blue metallic shine ( Fig. 4 ). Head small, with small prominent eyes, interocular distance 1.52 times longer than maximum eye diameter. Antennae compressed, acutely serrate. Pronotum medium sized, trapezoidal, 1.67 times wider than long at midline, median areola well developed with very weak lateral carinae. Elytra 3.84 times longer than width at humeri, with three fully developed primary costae, costa 1 reaching only one seventh of elytral length, secondary costae weak, often interrupted, cells rectangular, irregular. Phallus robust, with strongly projected ventral apical process, ventrally with characteristic hook ( Figs 11–12 ). Phallobase slender, extensively sclerotized.

Measurements. BL 9.7 mm, WH 2.32 mm, PL 1.10 mm, PW 1.83 mm, Edist 0.62 mm, Ediam 0.56 mm.

Etymology. The specific name refers to the locality data.

Distribution. Papua New Guinea, Mindik, known only from the type locality.

Remark. This distribution of this species partially overlaps with occurrences of several other similar metallic blue species. The metallic coloration of these taxa probably evolved as an aposematic signal and strong diversification in the shape of genitalia can be considered as an evidence that these species are probably distantly related ( Bocak 2001) and their coloration represents an aposematic signal and not an inherited ancestral character.

Figures

FIGURES 2 – 6. General appearance of Diatrichalus. 2 — D. buruensis sp. n., male; 3 — D. manokwarensis sp. n., male; 4 — D. mindikensis sp. n., male; 5 — D. robustus sp. n., male; 6 — D. mancus, male. Scales 2 mm.

FIGURES 7 – 24. Male genitalia (ventral and lateral views, respectively). 7, 8 — D. buruensis sp. n.; 9, 10 — D. manokwarensis sp. n.; 11, 12 — D. mindikensis sp. n.; 13, 14 — D. robustus sp. n.; 15, 16 — D. mancus; 17, 18 — D. dilatatus; 19, 20 — D. sinuaticollis; 21, 22 — D. xylobanoides; 23, 24 — D. niger. Scales 0.5 mm.