The short vein within the first submarginal cell (SCI) is variously described as vein 1r or the ‘spur vein’. This vein is obvious in many Thynninae, including virtually all Thynnini. However, it is absent or barely indicated in Iswaroidini, another of the Thynninae tribes.

The relative positions of the ‘recurrent veins’, particularly 2m-cu, and the 2nd submarginal cell cross vein (2r-m) is particularly important in distinguishing the Thynninae tribes.

The subfamily Diamminae consists of a single species, Diamma bicolor. While the females are easily identified (large, metallic blue, often seen moving freely above ground), males are less distinctive. Their forewing venation, however, provides a very good clue. In Diamminae, 2m-cu meets SCII. In nearly all other Thynninae, 2m-cu meets SCIII.

In many Thynnidae, the frons is produced above and between the antennal sockets. Viewed dorsally, this ventromedial region of the frons is therefore raised relative to the lateral regions.

The shape of then antennal prominence varies considerably between genera.

Both the epipygium (T7) and the hypopygium (S8) provide important clues to identification.

The epipygium is typically convex, as here, but in some genera it is produced apically into a plate before and above the apical margin. Note that such ‘subapical plates’ are quite distinct from the apical membranous plate, a widespread feature that may vary in width but is otherwise not particularly diagnostic.

The hypopygium is highly variable, particularly among the Thynninae.

2m-cu meets SCIII (so not Diamminae)

3rd interval of M: subequal to 2nd interval (3:3.5); more than half length 2r-m (3:3.8) (so neither Iswaroidini nor Agriomyini)

1r vein distinct (so neither Myzininae nor Iswaroidini)

frons produced above antennal sockets (ie antennal prominence present) (so not Anthoboscinae)

clyeus with sagittal (ie median) carina, not obviously branched

clypeus truncate apically

note broad mandibles!

antennal prominence slightly raised above each antennal socket

metasoma fusiform, without strong constrictions

hypopygium with short, slightly upturned apical spine

epipygium (T7): strongly convex, not flat (unlike most Tachynomyini); without subapical plate

hypopygium with: long, exposed dorsal surface that is multicarinate; rounded lateral lobes (‘basal angles’); short apical spine; apical margin rounded

metasoma: moderately sclerotised; moderately constricted between segments

S2-6 without posterolateral spines

S1 slightly angulate in profile

note that constrictions between segments are much less pronounced in this view (cf lateral view)

S1 weakly raised, without sagittal carina

pronotum: long dorsally; carinate anteriorly

propodeum rounded

head rounded posteriorly, not strongly concave (unlike most Tachynomyini)

pronotum: long (?) dorsally; carinate anteriorly

pronotum: long dorsally; carinate anteriorly

antennae long

propodeum: evenly rounded, without distinct dorsal and vertical faces; without carina

hypostomal carina with fringe of setae of varying lengths

hypostoma broad, concave, polished

front coxae are large and concave ventrally, with a sharp ridge between dorsal and ventral faces

front coxae are large and concave ventrally

front coxa wide, with rounded (convex) dorsal surface

prementum with tuft of long, posteriorly directed setae

prementum with tuft of long, posteriorly directed setae

both 1m-cu & 2m-cu join the M vein proximal to 2r-m (ie both recurrent veins meet SCII)

without even a trace of 1r vein

without even a trace of 1r vein

frons strongly produced above antennal sockets (ie WITH antennal prominence)

metasoma strongly fusiform in dorsal view, glossy

without constrictions between segments (except between segments 1 & 2)

T1 longer than wide, considerably narrower than T2

antennal prominence with narrow carina, V-shaped & contiguous with sagittal carina to clypeus

antennal sockets directed ventrolaterally

clypeus with sagittal carina, contiguous with V-shaped carina of antennal prominence

lateral regions of clypeus long, rounded

apex of clypeus narrow, weakly trilobed, not strongly produced beyond lateral regions

pale colour: lateral lobes of clypeus; inner eye margins, mandibles for basal 2/3

metasoma fusiform in lateral view

pale, lateral spots T1-4 & S2-4

propodeum rounded (without delineated dorsal and lateral surface), with shallow sagittal depression

T1 near triangular, with pair of white marks posterolaterally

epipygium convex, without subapical plate

apices of parameres (pale) exposed

hypopygium rounded, without spines or teeth, WITH fringe of stout setae arising subapically

apices of parameres (pale) exposed

pronotal disc rounded anteriorly, without carina

pronotum widest posteriorly, lateral edges rounded, converging anteriorly, without transverse carinae or groove

front coxae with large, pale spots anteriorly

femora partly red/orange

pale, lateral spots T1-4

hind femora red (except black basally & apically)

scutellum & metanotum with narrow, transverse pale bands mediapically

medial shallow depression, broadened posteriorly

2m-cu meets SCIII, 1r distinct

1r distinct

frons strongly produced above antennal sockets

metasoma fusiform, not strongly constricted

hypopygium with apical spine, not strongly upturned

metasoma fusiform

clypeus long medially, broadly truncate, with sagittal carina

S1; roundly raised medially, but without sharp carina; highest posteriorly, then with short oblique posterior surface; without tubercle

S5 & S6 without posterolateral spines

hypopygium with broadly rounded basal angles, raised above level of spine

hypopygium with broadly rounded basal angles, raised above level of spine

epipygium without subapical plate