Discleroderma guamensis Azevedo, Vargas & Colombo, 2020

Azevedo, Celso O., Vargas, Juan M. & Colombo, Wesley D., 2020, Synopsis of world Discleroderma Kieffer (Hymenoptera, Bethylidae), Zootaxa 4742 (3), pp. 467-480 : 476-478

Discleroderma guamensis Azevedo, Vargas & Colombo , sp. nov.

Fig. 4 E–H

Description, female. Body 2.77 mm long. Forewing 1.78 mm long. LH 0.54 mm. WH 0.51 mm. WF 0.29 mm. HE 0.25 mm. WOT 0.14 mm. OOL 0.13 mm.

Color. Head dark castaneous, clypeus castaneous, antenna dark castaneous dorsally and castaneous ventrally, mandible castaneous, palpi light castaneous. Mesosoma dark castaneous, legs somewhat dark castaneous, tarsi light castaneous, wings hyaline, veins light castaneous. Metasoma dark castaneous, anterior area of sternites distinctly lighter.

Head. Head subbarrel-shaped in dorsal view, lateral margin outcurved, wider at level immediately posterior to eye top, sides of head little converging anterad, vertex outcurved. Gena not visible in dorsal view. Malar space large, about as long as proximal mandibular width. Malar sulcus absent. Anterior clypeal margin slightly thicker. Mandible with dorsal margin straight anteriorly, ventral margin incurved. Pedicel about 2.0 × as long as flagellomere I; mid flagellomeres slightly wider than longer. Frontal angle of ocellar triangle acute. Anterior margin of anterior ocellus crossing supra-ocular line. WH 0.94 × LH; WF 0.58 × WH; WF 1.19 × HE; OOL 1.18 × WOT. Intertorular space less than torular diameter. Frons coriaceous, punctures small, shallow and sparse. Frontal line carinate, very inconspicuous. Hypostomal carina conspicuous, evenly strongly arched, not angulate medially.

Mesosoma. Dorsum of thorax more coriaceous than frons, punctures large, shallow and dense. Pronotal flange short, surface subvertical. Anteromesoscutum medially longer than mesoscutellum. Notauli absent. Parapsidal signum incomplete anteriorly, thick, conspicuous, slightly outcurved, converging posterad. Mesoscutum-mesoscutellar sulcus evenly and slightly arched posterad laterally, little dilated laterally. Metapectal-propodeal disc with transverse anterior, metapostnotal median, first metapostnotal lateral and transverse posterior carinae; first metapostnotal lateral carina straight, incomplete posteriorly, lateral margin straight, parallel, disc weakly rugulose between and around first metapostnotal lateral carinae, otherwise coriaceous-weakly coriaceous. First abdominal spiracle elliptical, located on dorsal surface of metapectal-propodeal disc, not intercepted by lateral carina. Propodeal declivity coriaceous, without median carina. Lateral surface of metapectal-propodeal complex coriaceous. Mesopleuron weakly coriaceous, transepisternal line present only anteriorly, central pit minute. Forewing with prestigmal abscissa of R1 0.71 × as long as Rs&M. Hind wing with one proximal hamulus and three distal hamuli not evenly spaced. Mesotibia strongly spinose.

Metasoma. Tergite III without any tubercle; tergites IV–V with one pair of small callus-shaped tubercles, connected by transverse carina. Inter-tubercular space 1.0 × outer-tubercular space for both metasoma segments IV and V.

Material examined. Holotype female, [ UNITED STATES OF AMERICA] Guam I., Marianas , Fadang, 30 May 1945, beating vegetation, Col. & pres. by Henry S. Dybas, Lot 2089 ( BPBM).

Etymology. The specific epithet guamensis refers to the type locality Guam Island.

Remarks. This species is similar to D. dolium , and they could be treated as a single species under a strictly morphological criteria. Guam Island, however, is an isolated island 2,500 km apart from North Ceram in Indonesia, which makes it unlikely that populations from these two interbreed. The only differences between both species are in the size of the pedicel and that the shape of the hypostomal carina being slightly more conspicuous.

Figures

FIGURE 4. A–D. Discleroderma dolium sp. nov., ♀. A. Habitus; B. Head, dorsal view; C. Mesosoma, dorsal view; D. Metaso- mal process, lateral view. E–H. Discleroderma guamensis sp. nov., ♀. E. Habitus; F. Head, dorsal view; G. Mesosoma, dorsal view; H. Metasomal process, lateral view. Scales-bars: 200μm, except 500μm for A and E; 100μm for D and H.