Boreobythus, ENGEL & GRIMALDI, 2007

ENGEL, MICHAEL S. & GRIMALDI, DAVID A., 2007, Cretaceous Scolebythidae and Phylogeny of the Family (Hymenoptera: Chrysidoidea), American Museum Novitates 3568 (1), pp. 1-16 : 5

Boreobythus , new genus

TYPE SPECIES: Boreobythus turonius , new species .

DIAGNOSIS: Head elongate ( fig. 2 ); frontal prominence absent; clypeal apex weakly produced; malar space apparently more than onehalf basal mandibular width; face lateral to antennal torulus flat; compound eyes relatively small, length only slightly more than distance from upper tangent of compound eyes to preoccipital ridge; inner margins of compound eyes very minutely converging below; ocelli almost entirely obscured by fine layer of microscopic bubbles but apparently near upper tangent of compound eyes; occipital carina absent; pronotal collar present, dorsal surface of pronotum nearly 1.5 times as long as mesoscutum; propleura well developed, anteriorly forming a short neck; notauli absent; prosternum large, exposed, broadly triangular posteriorly ( fig. 2 ); parapsidal lines absent; forewing with open marginal cell; Rs long, much longer than pterostigma, terminating near anterior wing margin ( fig. 2 ), tubular over entire length; R 1 present on wing margin; pterostigma relatively small, margin within marginal cell convex; 1m-cu present, tubular; Rs + M tubular; Cu distad separation from M nebulous (i.e., abscissae basad and distad 1m-cu nebulous); first submarginal cell short; metafemur not flattened; tibial spur formula indeterminate from fossil; pretarsal claws simple.

ETYMOLOGY: The genus-group name is a combination of boreas (Greek, meaning ‘‘north wind’’) and – bythus (root of the type genus for the family, Scolebythus ). The name refers to the fact that this fossil comes from the furthest north paleolatitude among Cretaceous scolebythids. The name is masculine.

COMMENTS: Boreobythus has, perhaps, the most plesiomorphic habitus of any scolebythid, overall resembling a primitive bethylid, particularly in the shape of the head. However, despite the superficial shape of the head, the greatly enlarged and exposed prosternum, the laterally articulated protrochanters, and the enlarged propleura that form a short neck attest to its placement in Scolebythidae .

Figures

Figs. 1–3. Photomicrographs of Cretaceous Scolebythidae. 1. Female holotype of Boreobythus turonius, new genus and species (AMNH). 2. Female holotype of Zapenesia libanica, new genus and species (Azar 146- A). 3. Male holotype of Uliobythus terpsichore, new genus and species (Azar 157-A).