Xylotrupes, Hope, 1837

Rowland, J. Mark, 2011, Notes on nomenclature in Xylotrupes Hope (Scarabaeidae: Dynastinae Dynastini), Insecta Mundi 2011 (176), pp. 1-10 : 2-4

Xylotrupes taxa

Xylotrupes Hope 1837: 19 ; type sp. Scarabaeus gideon Linné , by monotypy Syn. Endebius Lansberge 1880: 122 ; type sp. X. florensis Lansberge , by monotypy

X. australicus australicus Thomson 1859: 18 ; Queensland, Australia; type at MNHN. Remarks: This taxon was originally described as X. australicus by Thomson (1859), but was subsequently treated as a subspecies of X. gideon by Endrödi (1951, 1976, 1985) and of X. ulysses by Rowland (2006a,b). It is here restored to species level within the Ulysses Species Group of Xylotrupes . For comparative morphology see Description of a new species, and Key to males of the Ulysses Species Group of Xylotrupes , below.

X. australicus darwinia Rowland 2006a: 9 ; comb. nov. [ex X. ulysses darwinia ]; Northern Territory, Australia; type at MAGD. Remarks: This taxon was described as a subspecies of X. ulysses in Rowland (2006a) and was so treated in Rowland (2006b). It is here treated as a subspecies of X. australicus because it shares with the nominate subspecies expression of only the beta male phenotype (see Rowland and Emlen 2009), the right raspular base is more than 30% of the total length of the right raspula and their distributions are disjunct. Xylotrupes australicus darwinia has attenuate cephalic horn tines, the right raspular spine is thinner than the left and the maximum body length is about 3.5 cm. However in X. australicus australicus the cephalic horn tines are stout and strongly recurved, the right and left raspular spines are of equal thickness and the maximum body length is about 5 cm.

X. beckeri Schaufuss 1885: 17 ; West Malaysia, Sumatra; type at ZMHB

X. carinulus sp. nov. [ex X. lamachus of authors, not Minck 1920]; Papua New Guinea, Irian Jaya, Aru Islands ; type at USNM. Remarks: See Description of a new species, below .

X. clinias clinias Schaufuss 1885: 194 ; Sulawesi and Maluku, Indonesia; type at ZMHB. Remarks: See Remarks under Description of a new subspecies, below .

X. clinias buru ssp. nov.; Buru Island , Indonesia ; type at ZMHB. Remarks: See Remarks under Description of a new subspecies, below .

X. damarensis Rowland 2006a: 22 ; stat. nov. [ex X. beckeri damarensis ]; Damar Island, Tanimbar Islands, Indonesia; type at ZMHB. Remarks: This taxon was described as a subspecies of X. beckeri in Rowland (2006a) and so treated in Rowland (2006b). Resolution of the attenuated inflection of horn scaling in alpha males and attenuate cephalic horn tines across population samples promulgates raising this taxon to species level in the Gideon Species Group of Xylotrupes , which consists of X. gideon , X. tadoana , X. sumatrensis , X. pachycera , X. inarmatus and X. damarensis .

X. falcatus Minck 1920: 220 ; Sanghir Islands , Indonesia ; type at ZMHB .

X. florensis florensis Lansberge 1879: 153 ; Lesser Sunda Islands, Indonesia; type unknown .

X. florensis tanimbar Rowland 2006a: 5 ; Tanimbar Islands , Indonesia ; type at ZMHB

X. gideon ( Linné 1767: 541) , as Scarabaeus ; Java; type at LSUK .

X. inarmatus Sternberg 1906: 172 ; Java; type at ZMHB .

X. lorquini lorquini Schaufuss 1885: 194 ; Sulawesi; type at ZMHB. Remarks: This taxon was originally described as X. lorquini by Schaufuss (1885), but was subsequently treated as a subspecies of X. gideon by Endrödi (1951, 1976, 1985) and of X. pubescens by Rowland (2006a,b). On the basis of raspular morphology this species is placed in the Pubescens Species Group of Xylotrupes which consists of X. pubescens , X. philippinensis , X. pauliani and X. lorquini . The uniquely and strongly inflected horn scaling promulgates restoring X. lorquini to species level in this group.

X. lorquini zideki Rowland 2003: 231 ; comb. nov. [ex X. pubescens zideki ]; Sumatra; type at USNM. Remarks: This taxon was described as a subspecies of X. pubescens in Rowland (2003) and was so treated in Rowland (2006a,b) but is here treated as a subspecies of X. lorquini because it shares with the nominate subspecies similarly inflected horn scaling and attenuated raspular morphology.

X. macleayi macleayi Montrouzier 1855: 19 ; Milne Bay Province of PNG, Vanuatu; type at ISNB. Remarks: This taxon was originally described as X. macleayi by Montrouzier (1855), but subsequently treated as a subspecies of X. gideon by Endrödi (1976, 1985) and as a taxon of unknown affinity by Rowland (2003). The type is an indeterminate beta male lacking genitalia, but new material indicates that it is a member of the Ulysses Species Group and specifically distinct from other members of that group as described under Description of a new species, and Key to males of the Ulysses Species Group of Xylotrupes , below.

X. macleayi szekessyi Endrödi 1951: 244 ; comb. nov. [ex X. gideon szekessyi ]; Solomon Islands; type at HNHM. Remarks: This taxon was originally described as X. gideon szekessyi by Endrödi (1951) and was so treated in Endrödi (1976, 1985). It is here treated as a subspecies of X. macleayi on the basis of the characters indicated under Description of a new species, and Key to males of the Ulysses Species Group of Xylotrupes , below.

X. meridionalis meridionalis Prell 1914: 216 ; India; type at ZMHB .

X. meridionalis taprobanes Prell 1914: 217 ; Sri Lanka; type at ZMHB .

X. mniszechi Thomson 1859: 18 ; Himalaya; type at MNHN .

X. pachycera Rowland 2006b: 22 ; stat. nov. [ex X. gideon pachycera ]; Borneo; type at AMNH. Remarks: This taxon was described as a subspecies of X. gideon in Rowland (2006a). Lack of facultative expression of beta male phenotypes in population samples of this taxon and the greatly shortened and thickened cephalic and pronotal horns in large males promulgates elevation of this taxon to species level in the Gideon Species Group of Xylotrupes , which consists of X. gideon , X. tadoana , X. sumatrensis , X. pachycera , X. inarmatus and X. damarensis .

X. pauliani Silvestre 1997: 130 ; Sumatra; type at MNHN

X. philippinensis philippinensis Endrödi 1957: 65 ; stat. nov. [ex X. gideon philippinensis ]; Philippine Islands; type unknown. Remarks: This taxon was originally described as X. gideon philippinensis by Endrödi (1957) and was so treated in Endrödi (1976, 1985). It is here placed in the Pubescens Species Group of Xylotrupes with X. pubescens , X. lorquini and X. pauliani on the basis of raspular morphology. Alpha males of X. philippinensis are much smaller than those of X. lorquini . The beta males of X. philippinensis are much larger than those of X. pauliani and X. philippinensis lacks the heavy pronotal punctation of the latter. Xylotrupes philippinensis lacks the pubescent elytra and pronotum in the males of X. pubescens and has attenuate cephalic horn tines rather than the robust tines of X. pubescens .

X. philippinensis peregrinus Rowland 2006b: 13 ; comb. nov. [ex X. pubescens peregrinus ]; Taiwan islands; type at MSWB. Remarks: This taxon was described as a subspecies of X. pubescens in Rowland (2006b) but is here treated as a subspecies of X. philippinensis because it shares a similarly inflected horn scaling and similar, though reduced raspular morphology and alpha male horn scaling compared to the nominate subspecies.

X. pubescens Waterhouse1841: 539 ; Philippines; type at BMNH .

X. siamensis Minck 1920: 217 ; Southeast Asia; type at ZMHB .

X. sumatrensis sumatrensis Minck 1920: 218 ; Sumatra; type at ZMHB. Remarks: This taxon was originally described as X. sumatrensis by Minck (1920), but was subsequently treated as a subspecies of X. gideon by Endrödi (1951, 1976, 1985) and Silvestre (1997). It is here restored to species level within the Gideon Species Group of Xylotrupes , which consists of X. gideon , X. tadoana , X. sumatrensis , X. pachycera , X. inarmatus , and X. damarensis . Xylotrupes sumatrensis has distinctive raspular morphology relative to X. gideon which also occurs in southwestern Sumatra, and much greater development of the cephalic and pronotal horns compared to the other taxa of this species group.

X. sumatrensis tanahmelayu Rowland 2006a: 1 ; comb. nov. [ex X. gideon tanahmelayu ]; West Malaysia; type at USNM. Remarks: This taxon was described as a subspecies of X. gideon in Rowland (2006a) and was so treated in Rowland (2006b). It is here treated as a subspecies of X. sumatrensis because it shares with the nominate subspecies similar raspular morphology and a similarly inflected horn scaling pattern but X. sumatrensis tanahmelayu has a distinctly lower trajectory. Additionally, the integument of the male pronotum is glossier in X. sumatrensis tanahmelayu .

X. tadoana Rowland 2006a: 22 stat. nov. [ex X. beckeri tadoana ]; Flores Island, Indonesia; type at USNM. Remarks: This taxon was described as a subspecies of X. beckeri in Rowland (2006a) and so treated in Rowland (2006b). Subsequent resolution of the symmetry of the aedeagal orifice and distinctive raspular morphology promulgates raising this taxon to species level in the Gideon Species Group of Xylotrupes , which consists of X. gideon , X. tadoana , X. sumatrensis , X. pachycera , X. inarmatus and X. damarensis .

X. telemachos Rowland 2003: 226 stat. nov. [ex X. ulysses telemachos ]; Maluku, Indonesia; type at USNM. Remarks: This taxon was described as a subspecies of X. ulysses in Rowland (2003). It is a member of the Ulysses Species Group of Xylotrupes and specifically distinct from other members of this group in expressing only the beta male phenotype and the right raspular base is less the 20% of the total length of the right raspula. See Description of a new species, and Key to males of the Ulysses Species Group of Xylotrupes , below.

X. ulysses ( Guérin-Méneville 1830: 80) , as Scarabaeus ; Bismarck Archipelago; type unknown .

X. wiltrudae Silvestre 1997: 128 ; stat. nov. [ex X. beckeri wiltrudae ]; Borneo; type at MNHN. Remarks: This taxon was described as a subspecies of X. beckeri in Silvestre (1997) and so treated in Rowland (2003). It expresses both alpha and beta male phenotypes whereas X. beckeri expresses only the beta male phenotype. This promulgates raising X. wiltrudae to species level.

Description of a new species

Xylotrupes lamachus Minck (1920) has been the name most commonly used for Xylotrupes of the Papua New Guinea mainland. Minck’s original description of X. lamachus referred to two males from “Neu-Pommern” (= New Britain), one male and two females from “Dtsch.-N.- Guinea ” (=northeastern Papua New Guinea, Bismarck Archipelago, Solomon Islands, etc.) and one female from “Fr.-Wilhelmshafen N.- Guinea ” (=Madang). Present in the ZMHB are the two males labeled “Neu-Pommern”, one male but only one female labeled “Dtsch. N.- Guinea ” and no specimens labeled “Fr.-Wilhelmshafen N.- Guinea ”. The above three males and one female each have “Typus” labels. However, all three male syntypes are clearly identifiable as X. ulysses ( Guérin-Méneville 1830) , which is known only from the Bismarck Archipelago. The male syntypes of X. lamachus and males of X. ulysses from New Britain and New Ireland share the following unique combination of morphological attributes: The pronotal carinae are strongly produced in large specimens such that in lateral view they extend well beyond the anterior midline of the pronotum; the right raspular basal process is distinctly produced and acuminate; the left raspular base is oval; the elytra are glossy because the sculpturing is almost obsolete. Conversely, all known males from the Papua New Guinea mainland and Irian Jaya have distinctively weakly produced pronotal carinae in large males such that in lateral view they do not extend beyond the anterior midline of the pronotum; the right raspular basal process is only vaguely if at all produced and acuminate; the left raspular base is triangular; and the elytra are matte because the sculpturing is relatively strong.

All three male syntypes of X. lamachus are thus unequivocally identifiable as X. ulysses and the above female syntype is non-diagnostic and not determinable as any particular species of Xylotrupes . Thus, in accordance with ICZN (1999) Article 74.7 and Recommendations 74B, C and F, I am here designating a lectotype for Xylotrupes lamachus in order to fix usage of the name Xylotrupes lamachus Minck and to establish its synonymy with Xylotrupes ulysses (Guérin-Méneville) . The male lectotype of Xylotrupes lamachus is deposited at ZMHB and bears a purple label “Typus”, a white label “Neu-Pommern”, a red label “lamachus” and a red label “ Lectotype Xylotrupes lamachus Minck 1920 , designator: J.M. Rowland”. The lectotype is the syntype that Minck dissected and illustrated as figures 20a, 20m, 20o in the original description ( Minck 1920). One mandible, one maxilla, the labrum and endophallus of the lectotype were glued to points and cards by Minck and I have glued the raspulae of the lectotype to a card and these are mounted on the pin with the other labels. Lectotype measurements in mm: total length 55, body length 46, cephalic horn length 12.7, pronotal horn length 19.1, pronotal width 19.2, elytral length 29.2, elytral width 24.7, abdominal height 16.2. By designation of the lectotype the other males in the syntype series become paralectotypes. One paralectotype bears a purple label “Typus”, a white label “Neu Pommern”and a red label “ Paralectotype Xylotrupes lamachus Minck 1920 , designator: J.M. Rowland”. The other paralectotype bears a purple label “Typus”, a white label “Dtsch. Neu Guinea ” and a red label “ Paralectotype Xylotrupes lamachus Minck 1920 , designator: J.M. Rowland”. The raspulae of the latter specimen is glued to a card which is mounted on the pin with the other labels. With designation of the above syntype of X. lamachus as lectotype I declare X. lamachus to be a junior subjective synonym of X. ulysses , new synonymy.

This action leaves the Xylotrupes populations of mainland Papua New Guinea and Irian Jaya without a species name. Therefore, the following new species is here described.