Echinoaesalus borneoensis Huang & Imura 2011, new status
Creators: name: Huang, Hao
name: Bartolozzi, Luca
name: Chen, Chang-Chin
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Lucanidae
Echinoaesalus
Echinoaesalus borneoensis

description: Echinoaesalus borneoensis Huang & Imura, 2011 new status
(Figs. 2, 9, 11, 37–38, 55, 59–62, 78–79, 91–92, 104–106)
Echinoaesalus hidakai borneoensis Huang & Imura, 2011
Material. INDONESIA: 1 ♂ (L01), BORNEO, South Kalimantan Province, Kandangan district, Loksado, 17 km NE, 900 m, 15.XI.1997 – 15.XI.1998; 1 ♂ (L11), MALAYSIA, Sabah, Mt. Kinabalu, near park headquarters, 21– 22.X.2006, R. Novak; 1 ♀ (L07), MALAYSIA, Sabah, Crocker range, 5.III.2007. MALAYSIA: 1 ♀ (L27), Kelantan, 60 km NE of Tanah Rala, Tanah Kerajaan, 1000 m, 12–30.IV.2007, P. Cechovsky; 1 ♀ (L16), Kelantan, 30 km NW of Gua Musang, Ulu Lalat Mt., Kampong Sungai Om, 800–1000 m, 22.V.–14.VI.2012, P. Cechovsky.
Remarks. This taxon was originally described as a subspecies of E. hidakai, based on the similarity between them and overall lack of material. However in the new material we have examined, female specimens of both taxa were collected from the same area in Kelantan, Malaysia. An examination of female genitalia shows significant differences between the two taxa in length of spermathecal duct, size of hemisternite, and length of stylus. This sympatric fact strongly supports Echinoaesalus borneoensis to be a separate species.
The following differences are found between E. borneoensis and E. hidakai, based on an examination of additional specimens: 1) mentum in both sexes more transverse in E. borneoensis than in E. hidakai, with clearly defined round pits in E. borneoensis but with elongate and connected pits in E. hidakai; 2) pronotal plate of both sexes shorter in E. borneoensis than in E. hidakai, more evident in female; 3) 9th abdominal segment of male shorter in E. borneoensis than in E. hidakai; 4) median lobe of parameres markedly thinner in E. borneoensis than in E. hidakai, completely pigmented in E. hidakai but with lateral colorless splits in E. borneoensis; 5) parameres markedly shorter in E. borneoensis than in E. hidakai; 6) hemisternite of female genitalia smaller with shorter FIGURES 77–89. 9th abdominal segment of male in ventral view under same scale (scale bar 1 mm). 77, Echinoaesalus hidakai, L12, western Malaysia; 78, E. borneoensis, L11, Borneo; 79, E. borneoensis, L01, Borneo; 80–86, E. timidus; 80, L08; 81, L02; 82, L17; 83, L23; 84, L21; 85, L22; 86, L18; 87, E. sabahensis, L14, Borneo; 88, E. cechovskyi, holotype, western Malaysia; 89, E. gedeensis, holotype, Java. Arrow directed to pigmented terminal end of ventral plate.
stylus in E. borneoensis than in E. hidakai; 7) spermathecal duct in E. borneoensis nearly half as long as in E. hidakai.
Nevertheless, E. borneoensis and E. hidakai are very similar and share nearly all the remaining characters other than the characters above. We did not find any differences in labium, maxilla, antenna, and hindwing between the two species. The sexual dimorphism of E. borneoensis is exactly the same as that of E. hidakai. It is very possible that all species of the E. hidakai group have the same sexual dimorphism, different from that of the E. matsuii (Araya, 1993) group by having no sexual dimorphism in posterior margin of last visible abdominal ventrite.
Male genitalia (Figs. 91–92). The male genitalia taken from the new material fit the original description (Huang et al. 2011) in all details.
Female genitalia (Figs. 104–106). Generally as in E. hidakai, but with smaller hemisternite, shorter stylus, and markedly shorter spermathecal duct.
Distribution. Known from Borneo (type locality) and the Malay Peninsula. Sympatric with E. hidakai in the Malay Peninsula.
description: Published as part of Huang, Hao, Bartolozzi, Luca & Chen, Chang-Chin, 2015, Notes on the genus Echinoaesalus Zelenka, 1993 (Coleoptera: Lucanidae), with the description of a new species from the Malay Peninsula, pp. 553-565 in Zootaxa 4039 (4) on pages 554-558, DOI: 10.11646/zootaxa.4039.4.5, http://zenodo.org/record/241183