Zeachremylus Belokobylskij, 2018

Belokobylskij, Sergey A., 2018, An enigmatic new genus of cyclostome braconid wasp (Hymenoptera: Braconidae) from New Zealand, Zootaxa 4403 (3), pp. 594-600 : 595-596

Zeachremylus Belokobylskij , gen. nov.

Type species. Zeachremylus wardi Belokobylskij , sp. nov.

Diagnosis. Zeachremylus gen. nov. has an enigmatic subfamily position. On one hand, it is similar to the pamboline genus Chremylus Haliday, 1833 , but distinctly differs from it by entirely and coarse rugose-reticulate sculpture on mesosoma, rather distinctly separated antennal sockets, reduced numbers of maxillary and labial palpal segments, distinctly elongated scape, presence of long setae on dorsal margin of hind tibia, absence of second radiomedial (r-m) vein in fore wing and nervellus (cu-a) in hind wing, distinctly apically widened brachial (first subdiscal) cell and strongly medially curved mediocubital (M+CU) vein in fore wing.

On the other hand, because of the absence of the nervulus in the hind wing and the resulting widely open submedial (subbasal) cell, this new genus has some similarities with the mesostoine (according to molecular data: Quicke at al. 2018) genus Austrohormius Belokobylskij, 1989 , but the new genus is distinctly different in the following characters: head and mesosoma entirely coarsely rugose-reticulate, malar suture absent, small number of antennal segments, distinctly elongated scape, notauli present and complete, prescutellar depression long and almost straight, second radiomedial (r-m) vein of fore wing absent, and second and third tergites not enlarged.

Description. Head weakly transverse ( Fig. 2 ), not depressed dorso-ventrally ( Fig. 3 ), almost entirely densely rugose ( Figs 2–5 ). Ocelli small, arranged in almost equilateral triangle. Frons weakly convex, without median keel or furrow. Eyes glabrous. Occipital carina present, complete dorsally and ventrally, below fused with hypostomal carina. Hypostomal keel wide and coarse. Malar suture absent. Clypeal suture shallow and in upper part almost indistinct. Hypoclypeal depression rather large and oval. Mandible wide and massive. Postgenal bridge absent. Maxillary palpus ( Fig. 4 ) rather short, 5-segmented, its fifth segment longer than fourth segment; labial palpus short, 3-segmented, middle segment weakly shortened and wide. Antenna ( Fig. 6 ) thickened, 12-segmented. Scape narrow basally, evenly widened towards apex, long, without apical lobe and basal constriction. Pedicel subspherical. First flagellar segment longer than second segment. Apical segment pointed apically, but without spine.

Mesosoma ( Figs 7, 8 ) not depressed. Neck of promesosoma rather short, weakly convex dorsally (lateral view). Pronotal keel distinct in anterior third, pronope absent. Propleural dorsoposterior flange rather wide and short. Mesonotum distinctly and roundly elevated above pronotum. Median lobe of mesonotum without anterolateral corners, with distinct medial furrow in posterior half. Notauli shallow, very shallow posteriorly, narrow, complete, crenulated, fused to each other weakly before prescutellar depression. Prescutellar depression short medially and rather long laterally, deep and coarsely crenulated. Scuto-scutellar suture distinct, prominent. Scutellum weakly convex, with distinct lateral carinae. Metanotum with short, wide and subpointed median tooth (lateral view). Subalar depression rather deep and narrow. Precoxal sulcus (sternaulus) shallow, rather wide, long, weakly sinuate, oblique, distinctly crenulated. Prepectal carina distinct and complete. Postpectal carina absent. Mesosternal medial furrow deep and wide. Metapleural flange long, wide, subpointed apically. Metapleuron in upper anterior part with deep subcircular depression. Propodeum with areas distinctly delineated by carinae ( Fig. 15 ); with distinct high and wide longitudinal lateral ridges.

Pterostigma of fore wing wide, triangular ( Fig. 10 ). Radial vein (r) arising perpendicularly from middle of pterostigma. Parastigma relatively narrow and long. Radial (marginal) cell weakly shortened ( Fig. 10 ). First radiomedial vein (2RS) present; second radiomedial vein (r-m) absent ( Fig. 10 ). Second radial abscissa (3RSa) strongly curved in basal half, then almost linear till apex. Recurrent vein (1m-cu) short, weakly postfurcal or interstitial ( Fig. 12 ). Mediocubital vein (M+CU) sinuate, distinctly curved to longitudinal anal vein (1A) in apical third. Nervulus (1cu-a) short and weakly postfurcal or sometimes interstitial. Discoidal (first discal) cell petiolate. Basal (1M) and recurrent (1m-cu) veins strongly convergent posteriorly. Parallel vein (2CU) not interstitial ( Fig. 12 ), arising from anterior third of distal margin of brachial (first subdiscal) cell, but sometimes almost interstitial. Brachial (first subdiscal) cell distinctly widened towards apex. Both transverse anal veins (1a and 2a) absent. Hind wing ( Fig. 11 ) with three-four hamuli and with singly long slender setae on top of first costal abscissa. First abscissa of costal vein (C+Sc+R) shorter than second abscissa (SC+R). Medial (subbasal) cell rather narrow, weakly widened towards apex, 0.3–0.4 × as long as hind wing. Radial vein (RS) unsclerotised; radial (marginal) cell without additional transverse vein (r), almost parallel-sided. Nervellus (cu-a) absent ( Figs 11, 13 ); longitudinal anal vein present. Submedial (subbasal) cell widely open. Recurrent vein (m-cu) present, long, distinctly curved towards base of wing.

Legs. Hind coxa medium-sized, without basoventral tooth or corner. All femora entirely coarsely rugosereticulate. Fore and middle femora claviform. Hind femur narrow and curved basally, widened apically in lateral view, rather compressed and weakly curved in dorsal view. Hind tibial spurs medium length, glabrous ( Fig. 9 ). Hind tarsus narrowed towards apex. Basitarsus of hind tarsus about 0.7 × as long as second–fifth segments combined. Claw distinctly curved in apical half.

Metasoma ( Fig. 14 ). First tergite not petiolate, wide and short ( Figs 14, 15 ). Acrosternite short, about 0.2 × as long as first tergite, its posterior margin situated distinctly before spiracles. Dorsope of first tergite small; basolateral lobes absent; spiracular tubercles small, situated in basal third of tergite; dorsal carinae complete, widely separated, weakly curved, subparallel. Suture between second and third tergites mainly or completely absent, partly present only laterally. Second and third tergites combined covering more than half of the metasoma length behind first tergite (dorsal view). Second–fifth tergites without separated laterotergites; spiracles situated on fold or below it. Hypopygium obtusely rounded apically. Ovipositor shorter than metasoma; apex simple, without tubercle dorsally and serration ventrally ( Fig. 16 ).

Etymology. From New Zealand, the country in which the new genus was collected, and Chremylus , the name of a similar genus. The gender is masculine.

Biology. Perhaps a parasitoid of an insect developing in the guano of bats, Mystacina spp. ( Mystacinidae ).

Distribution. Australasian region ( New Zealand).

Figures

FIGURES 1–9. Zeachremylus wardi gen. et sp. nov. (female, holotype). 1, Body, dorsal view. 2, Head, dorsal view. 3, Head, front view. 4, Head, latero-ventral view. 5, Head, lateral view. 6, Antenna. 7, Mesosoma, lateral view. 8, Mesosoma, dorsal view.9, Hind tibia.

FIGURES 10–16. Zeachremylus wardi gen. et sp. nov. (female, holotype). 10, Fore wing. 11, Hind wing. 12, Fore wing, median part.13, Basal half of hind wing. 14, Metasoma, dorsal view.15, Propodeum and basal half of metasoma, dorsal view. 16, Ovipositor, lateral view.