Xylotrupes carinulus, Rowland, 2011

Rowland, J. Mark, 2011, Notes on nomenclature in Xylotrupes Hope (Scarabaeidae: Dynastinae Dynastini), Insecta Mundi 2011 (176), pp. 1-10 : 5-6

Xylotrupes carinulus sp. nov.

Fig. 1-2 , 5

Types. Male holotype labeled “Wau Valley, Morobe Province, PNG, elevation 1200 m, 31 May 2000, Michael Hudson” and “ Holotype / Xylotrupes carinulus Rowland 2011 ” deposited at USNM.

Paratypes: 199 males, Wau Valley , Morobe Province, PNG, elevation 1200 m ( ZMHB, AMNH, BMNH, USNM, BPBM, MSWB, JMRC, FSCA) ; 19 males, Paglum , Mt. Hagen, Nov. 1953, Erik N. Kjellesvig- Waering ( FSCA) ; “W. Irian” 1 male ( JMRC) ; Kar Kar Island 1 male ( BPBM) ; Fak-Fak , Irian Jaya ; 13 males ( JMRC) ; Manakaeri, Irian Jaya 6 males ( TAMU), 1 male ( JMRC) ; Aru Islands , 2 males, ( ZMHB) .

Etymology. The name carinulus combines the Latin word roots carin (a keel) and ulus (small) and refers to the characteristically reduced size of the pronotal carinae in the males of this species.

Description. Measures of male holotype and paratypes in mm (range of 12 paratypes): Total length 66 (37-66), body length 50 (35-50), cephalic horn length 18.8 (6.2-20.3), pronotal horn length 33.4 (10.3- 34.2), pronotal width 20.7 (14.0-20.1), elytral length 32.1 (23.6-32.3), elytral width 27.9 (19.3-27.9), abdominal height 17.6 (12.0-16.5). Head: Cephalic horn denticle absent; mandible with two denticles. Thorax: Pronotal horn expression dimorphic and allometric shape sigmoidal; pronotal carinae weak in males, in lateral view not extending to anterior midline of pronotum; pronotal punctation strong in small males and moderate in large males; male elytra matte, sculpturing almost rugose, stronger in small males. Genitalia: Parameres essentially symmetric; paramere blades angled toward orifice; right raspular spine sharply curved, basal process weak or absent; left raspular spine similar in size to right raspular spine, though more strongly curved; left raspular base triangular; basal raspular piece shorter than right raspula. Color: Males dark reddish brown, slightly bicolored.

Comparisons. Xylotrupes carinulus is morphologically most similar to X. macleayi , X. ulysses , X. clinias , and X. falcatus in lacking a cephalic horn denticle in alpha males, having similar sized left and right raspular spines, and having triangular left raspular bases. Xylotrupes carinulus differs from X. macleayi , X. ulysses , and X. clinias in having greatly reduce pronotal carinae and shares this feature with X. falcatus . The latter species differs from X. carinulus in having strongly angled right raspular base relative to the plane of the spine.

Distribution. Papua New Guinea, Irian Jaya, Aru Islands.

Remarks. The new species X. carinulus is the common and only known species of Xylotrupes occurring on mainland Papua New Guinea and Irian Jaya. In previous publications these geographic populations were referred to as X. lamachus ( Paulian 1947) , X. gideon lamachus ( Endrödi 1951, 1976, 1985; Szent-Ivany 1969) and X. macleayi lamachus ( Silvestre 2003b) .

Description of a new subspecies

Xylotrupes clinias occurs from Sulawesi through Maluku at least to the Kei Islands, Indonesia. However, the populations of the Maluku island of Buru are found to have substantial and consistent morphological differences in genital morphology with regard to the other known populations of X. clinias . These Xylotrupes of Buru Island are here described as the following new subspecies.

Figures

Figures 1-4. Raspulae. 1-2)X. carinulus sp. nov. 1) Right raspula. 2) Left raspula. 3-4) X. clinias buru ssp. nov. 3) Right raspula. 4) Left raspula.

Figures 5-6. Male holotypes. 5) X. carinulus sp. nov.; total length 66 mm. 6) X. clinias buru ssp. nov.; total length 69 mm.