Strongylogaster Dahlbom, 1835

Liu, Mengmeng, Li, Zejian & Wei, Meicai, 2021, Review of Strongylogaster Dahlbom (Hymenoptera: Tenthredinidae) from Zhejiang Province, China, with the description of a new species, Zoologia (e 63051) 38, pp. 1-7 : 2

Strongylogaster Dahlbom, 1835

Diagnosis. Body and wings long. Clypeus short, anterior margin slightly emarginated; eyes large and elliptical, distance between eyes usually broader than length of eye; mandibles stubby, with 2–3 symmetrical teeth, apical tooth weakly curved; temple short, lateral sides narrowed in dorsal view, postocellar area broader than long, hind orbit rounded, occipital carina short or absent; frons conspicuous, with a distinct frontal ridge; malar space 0.3–1.3 times diameter of median ocellus; antennae stout, antennomere 2 broader than long, antennomere 3 approximately as long as antennomere 4; epicnemium narrow, distinctly elevated, epicnemial groove distinct; mesepimeron with a distinct transverse middle carina, lower part of anepimeron concave; apex of inner spur of fore tibia bifid, metabasitarsus much shorter than following four tarsomeres together; tarsal claw without basal lobe, inner tooth absent or small and remote from outer tooth; fore wing with vein 1M weakly convergent or parallel with 1m-cu towards pterostigma, base of vein Rs+M distinctly curved, vein cu-a joining cell 1M at about middle, cell 2M clearly longer than broad, anal cross-vein usually absent; hind wing with cells Rs and M closed, anal cell sessile or with a short petiole; ovipositor sheath usually with lateral branches or scapes, narrow and long in few species; lamnium of lancet longer than radix, mostly with regular serrulae; valviceps of penis valve long oval, dorsal margin with minute teeth.

Remarks. Strongylogaster is morphologically similar to Thrinax Konow, 1885 , but it can be distinguished by the following characters: epicnemium distinctly elevated, epicnemial groove broad and deep; anepimeron without a membranous area; frontal ridge low and obtuse; occipital carina absent; the anal cell of fore wing usually without a cross-vein; ovipositor sheath usually with lateral branches or scopas. Thrinax can be differentiated by the following features: epicnemium flat, epicnemial groove suture-like or vestigial; anepimeron usually with a distinct membranous area; the frontal ridge distinctly raised, occipital carina well defined on lower hind margins; anal cell of fore wing with a suberect cross-vein, saw sheath always simple and slender towards apex. At present, 44 previously known species have been recorded worldwide. Among them, 17 species occur in China based on Strongylogaster specimens available in our lab (ASMN).