Thynninae, TachynomyiniKerri-Lee HarrisNovember 03, 2026to Thynnine Hub

Phymatothynnus (specimen #070)

Thynninae, TachynomyiniKerri-Lee HarrisNovember 03, 2026to Thynnine Hub

Workbook

Collected in Malaise trap (GMP 66369) during the week 17th–24th Oct 2026 (specimen ID #070)

THYNNINAE: Tachynomyini: Phymatothynnus nitidus ‘complex’

Having worked through the various options, I am confident that this is Phymatothynnus. The genus is known from our local region, and meets the diagnostic criteria described by Brown (2025).

see Thynnine hub for detailed summary matrices

While specimen #070 is similar in many characters to specimen #042, the clypeus shape is distinct. The clypeus in specimen #070 has an obvious carina, a narrower apex, and lacks lateral teeth. However, both specimens key to Phymatothynnus nitidus complex.

see specimen #042 notes for details, including key steps

Thynnidae

head-body length 11mm

antennae

apical 6 segments strongly arcuate

clypeus (frontal view)

clypeus short, without distinct carina

apex protruberant, narrowly truncate medially, not emarginate

single lateral tooth on each side of truncation, well separated from medial truncation

antennal prominence (dorsolateral view)

antennal prominence with complex structure:

- emarginate medially (dotted arrow), the emargination flanked by teeth (yellow arrows)
- lateral carinae (solid white arrows) and smooth, broad, triangular, lateral face (dotted arrow)

terminalia (dorsal view)

hypopygium: simple, rounded; small apical knob; distinct basal notch on lateral margin

epipygium without carina

terminalia (lateral view)

epipygium relatively flat in profile

hypopygium (ventral view)

hypopygium with: small, apical, knob-like spine; distinct basal notches; long thin setae extending beyond apex

hypopygium (ventrolateral view)

hypopygium with: small, apical, knob-like spine; distinct basal notches; long thin setae extending beyond apex

The following is my justification for excluding other options among the Thynnidae and Tiphiidae.

Thynninae: Thynnini

Family THYNNIDAE, based on:

3 submarginal cells & frons produced above antennal sockets (so not Tiphiidae: Tiphiinae)

Subfamily THYNNINAE, based on:

frons produced above antennal sockets (so NOT Anthoboscinae)
forewing with distinct 1r vein (so NOT Myzininae)
forewing with 2m-cu meeting SCIII (so NOT Diamminae)

Tribe Tachynomyini most likely, based on:

forewing with 3rd interval distinctly shorter than 2nd interval of M, & shorter than half length 2r-m (so NOT Thynnini)
forewing with distinct 1r vein, almost complete (so NOT Iswaroidini & unlike most Agriomyini)
six apical segments of antennae strongly arcuate (so NOT Neozeleboria, Pentazeleboria of tribe Agriomyini)
hypopygium rounded, with minute apical spine (unlike all Rhagigasterini except Eirone)
vertex not lengthened (unlike most Eirone)

Phymatothynnus (Tachynomyini) is a good match, including the following diagnostic features:

Antennal shape: the apical 6 or more segments are strongly arcuate.
Hypopygium: there is a distinct notch basal notch on the lateral margin.

References

Brown, G. 2025. Revision of the Australian Thynnidae and Tiphiidae (Hymenoptera). Zootaxa 5681 (1): 001-862 https://doi.org/10.11646/zootaxa.5681.1.1

This is a workbook page … a part of our website where we record the observations and references used in making species identifications. The notes will not necessarily be complete. They are a record for our own use, but we are happy to share this information with others.

Kerri-Lee Harris