Balcha levicollis (Cameron)

Gibson, Gary A. P., 2005, The world species of Balcha Walker (Hymenoptera: Chalcidoidea: Eupelmidae), parasitoids of wood-boring beetles, Zootaxa 1033 (1), pp. 1-62 : 39-41

Balcha levicollis (Cameron) ( Figs. 43 , 54 )

Elemba levicollis Cameron, 1908: 151–152 . Type data: [ Malaysia], Borneo , Kuching, October 1906, John Hewitt. Holotype female by monotypy (BMNH type no. 5.952, examined).

Eusandalum levicollis ; Hedqvist, 1961: 109. Change of combination by inference through synonymy of Elemba Cameron with Eusandalum Ratzeburg.

Balcha levicollis ; Gibson, 1989: 67. Change of combination.

Additional material examined. ORIENTAL. MALAYSIA: [Malaya] Singapore (1♀ BMNH) . [Sabah] Borneo , Sandakan (2♀, 1♂ USNM) ; Buttun Point [Tanjong], 300ft., VI.1937, K.M. Walsh (1♀ BMNH) . Sarawak, Mt. Matang , 15.XII.1913 (1♀ BMNH) ,

23.I.1914, 2000 ft. (1♀ BMNH), G.E. Bryant .

Description. FEMALE. Length, 15–16 mm. Antenna dark except scape sometimes partly to almost entirely yellowish­orange; scape oval in cross­section and with outer surface flat at least apically and bare medially or basomedially; Fl 1 slightly shorter than apical width and slightly less than half as long as pedicel; Fl 2 about 1.2–1.5 x as long as clava. Head with punctures and interstices on parascrobal region not contrasting distinctly in color, the face usually dark purple or sometimes with blue to green luster under some angles of light and clypeus and interantennal region sometimes with greenish luster; ocellar region and vertex dark except variably broadly along upper inner orbit, with dark region extending as posteriorly tapered band medially in region between posterior ocelli and laterally behind each ocellus, but posterior surface of head usually extensively purple to blue under some angles of light, particularly on smooth, bare band along outer orbit. Face with setiferous punctures (cf. Fig. 19), the punctures closely crowded toward, but remaining distinct even near, oral margin, dorsally usually at least partly more widely separated by smooth or virtually smooth interstices, except about dorsal third to half of parascrobal region flat with more crowded and increasingly shallower and/or smaller punctures, being mostly punctulate­reticulate (cf. Fig. 20) or rugulose­coriaceous (Fig. 19) except coriaceous near ocelli, and uniformly setose with white to light brown setae. Scrobal depression with scrobes smoothly merging into channel; scrobes smooth and shiny, dark or with purple luster under some angles of light; channel purple ventrally and dorsally dark, coriaceous and sparsely setose.

Pronotum dark anteriorly and purple posteriorly and laterally; finely coriaceous to transversely coriaceous­aciculate and quite shiny. Tegula yellow to brown. Mesoscutum purple with variably distinct notaular and parapsidal bands, the bands either separate, and sometimes extending distinctly only about half length of mesoscutum, or forming ­like pattern and then with parapsidal band narrowed posteriorly to extend linearly to inner angle of axilla and with notaular band broadly truncate along base of scutellum (cf. Fig. 17 ). Mesoscutum (cf. Fig. 31 ) alveolate laterally, dorsally the punctures smaller and shallower, particularly between notauli and near parapsidal line; with broad, shallow, longitudinal depression over about posterior half anterior to level of inner margin of axilla, but sculpture not differentiated from surrounding cuticle; with quite uniform, white to brownish hairlike setae. Scutellum with dark band medially (cf. Fig. 17 ), to entirely purple or with some bluish luster under some angles of light; rugulose­coriaceous to more distinctly punctate with coriaceous subsculpture and with low median ridge (cf. Fig. 31 ), but sculpture at most obscurely aligned into irregular rugae. Metanotum purple except for brownish­hyaline dorsal margin of dorsellum; dorsellum ( Fig. 43 ) thin, in single vertical plane, coriaceous to coriaceous­reticulate with a few longitudinal rugae ventrolaterally, and bare; precrenular region of panel with 2 rows of seta at least near dorsellum. Acropleuron with distinct, elongate­ovate, rugulose­coriaceous subalar region separating punctate­alveolate prealar region from postalar region having longitudinally aligned reticulate­punctate sculpture ( Fig. 54 ); uniformly purple or with punctures violaceous under some angles of light and subalar region often dark. Lower mesepimeron punctatereticulate to reticulate­rugulose. Metapleuron coriaceous dorsally to extensively reticulaterugulose over distinct coriaceous subsculpture except for crenulate furrow along posterior margin. Propodeum purple or paraspiracular region more commonly with blue luster under some angles of light; paraspiracular region setose; callus comparatively smooth and shiny dorsally but with vertical lateral surface entirely, irregularly punctate­rugulose ( Figs. 43 , 54 ); plical region setose, carinate margin of foramen distinctly, ­like recurved to anterior margin of propodeum and inclined or almost vertical medially as short, high median carina, the region lateral to carina variably deeply concave and strongly crenulate ( Fig. 43 ). Forewing with vannal area and cubital area both brownish, and medial fold sometimes obscurely brownish beyond basal cell; vannal area with subcubital line of setae extending over about apical half. Legs uniformly yellowish­orange to dark brown.

Petiole composed almost entirely of vertically raised, smooth and shiny rim ( Fig. 43 ). Gaster in dorsal view dark brown or with slight purple luster, in lateral view all terga except syntergum with variably conspicuous purple luster; slightly more than twice length of head and mesosoma combined. Syntergum about two­thirds as long as remaining gaster and in lateral view about 9–11 x as long as high; uniformly setose, sculptured and tapered posteriorly, with cercus at basal margin.

MALE. Length, 7.3 mm. Similar to female in sculpture and setal pattern; structure similar to female except as follows: propodeum longer with plical region delimited by a W­like carinal complex formed by strong, sinuous plical carinae and inverted Y­ shaped median carina; petiole larger, in posterior view almost semicircular, smooth and shiny; gaster pedunculate, with Gt 1 and Gt 2 comparatively narrow, smooth and shiny, and subsequent terga conspicuously coriaceous, uniformly setose and increased in width to Gt 5. See discussion for color.

Biology. Unknown.

Discussion. The pedunculate shape of the gaster of the only known male likely is an artifact of preservation rather than diagnostic of males of the species, but additional specimens are required to confirm this. The male also has the head and mesosoma mostly bright green with purple restricted primarily to the acropleuron anteriorly and to the metapleuron. The distinct parapsidal and notaular bands are black with limited coppery luster under some angles of light, and although the parapsidal bands curve toward the notaular band they remain separated posteriorly, the tegula and legs are yellowish, and only the vannal area of the forewing is partly brownish. Additional males are necessary to determine whether some exhibit color patterns more similar to known females or whether males of both B. levicollis and B. anemeta might be much more brightly metallic than are females. Both sexes of B. levicollis are distinguished from all other species by the combination of a thin dorsellum, setose plical region of the propodeum, and reticulatepunctate postalar region of the acropleuron. Females, at least, are most similar to those of B. anemeta except for the different sculpture pattern of the acropleuron (cf. Figs. 53, 54 ). Insufficient females of both species have been seen to determine whether other minor differences detailed in the descriptions are also diagnostic.

Figures

FIGURES 39–46. 39–42. Mesosoma, dorsal: 39, Balcha cylindrica; 40, B. splendida; 41, B. camptogastra; 42, B. enoptra. 43–46. Metanotum and propodeum: 43, B. levicollis; 44, B. punctiscutum; 45, B. enoptra (cal = callus, dor = dorsellum, pcr = precrenular region of metanotal panel, ppr = propodeal plical region, psr = paraspiracular region); 46, B. elegans.

FIGURES 47–54. 47. Metanotum and propodeum: Balcha eximia. 48. B. indica (N. Am.): dorsellum and propodeal plical region. 49 and 50. Mesosoma, lateral: 49, B. punctiscutum; 50, B. indica (N. Am.). 51–54. Posterior half of acropleuron: 51, B. indica (holotype); 52, B. eximiassita; 53, B. anemeta; 54, B. levicollis (sar = subalar region of acropleuron).

FIGURES 9–18. Mesosoma dorsal: 9, Balcha laciniosa; 10, B. cylindrica; 11, B. elegans; 12, B. indica (N. Am.); 13, B. eximia; 14, B. eximiassita; 15, B. dictyota; 16, B. reticulata; 17, B. anemeta; 18, B. splendida (nob = notaular band, pnb = paranotaular band, ppb = parapsidal band).

FIGURES 31–38. Mesosoma dorsal: 31, Balcha anemeta; 32, B. punctiscutum; 33, B. indica (N. Am.); 34, B. indica (holotype); 35, B. elegans; 36, B. laciniosa (not = notaulus, pl = parapsidal line); 37, B. eximiassita; 38, B. reticulata.