F. X. Williams.
A Note on the Habits of Epactiothynnus opaciventris Turner, An Australian Thynnid Wasp.
Psyche 26:160-161, 1919.

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160 Psyche [December
A NOTE ON THE HABITS OF EPACTIOTHYNNUS
OPACIV'ENTRIS TURNER, AN AUSTRALIAN THYN- NID WASP.
BY FRANCIS X. WILLIAMS,
Hawaiian Sugar Planter's Experiment Station, Honolulu. During the winter of 1919, while engaged in entomological work on the Herbert River, North Queensland, for the Experiment Station of the Hawaiian Sugar Planter's Association, I made a few observations on this wasp. Epactiothynnus opaciventris is a moderately small species of the great Australian group of Thyn- nidse.
The male measures about 11
and the female 8 mm. in
length.
At the time of observation it was the most abundant of the few species of Thynnids then flying and its main food flower was Crotalaria sp., a common weed along roadsides and edges of '
fields.
I can find nothing in literature which relates to the egg and larval stages of any of the Australian Thynnidse, though Froggatt (Australian Insects, 1907) has dug up cocoons which yielded a large species. He states that these wasps probably parasitize the larvae of Lamellicorn beetles.
When females of Epactiothynnus were enclosed in a tumbler or shallow dish of soil with Lamellicorn grubs about 14 mm. long, and which were common in some of the cane fields, these grubs Fig. 1.
Larva of one of the Scarabzeid beetles, showing egg of Epactiothynnus opaciventn~s on its mid-ventral line.
(X 4.25, North Queensland.)




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19191 Williams-Habits of Epactiothynnus opaciventris Turner 161 were eventually stung to almost complete paralysis, just as the Scolias sting their prey. I did not observe the act of stinging, but a single Epactiothyunns would sometimes paralyze several grubs overnight.
Something was wrong, however, perhaps the weather was too cool, for of the many grubs stung but one had an egg upon it, and that failed to hatch. The egg (Fig. 1) is deposited along the mid-ventral line of the larva. It is pearly white, somewhat arcuate, thicker at one extremity, and measures 1.85 x 0.40 mm.
Tachynomyia sp., a darker and somewhat larger Thynnid was found also to paralyze the same species of beetle larva that was offered to Epactiothynnus.
In the bulk of the Thynnidse the strong-winged male, as he flies from place to place or feeds at flowers, carries his apterous Fig. 2. Female Thynnid on
reed; in such a position, she
awaits the advent of the winged
male, which carries her off.
(X 6.7, Sydney.)
and obese partner with him.
In cap-
tivity, at least, two Epactiothynnus
may remain paired for several days.
Fig. 2 is a drawing from life of a
small species of Thynnid taken near
Sydney.
She was first observed crawl-
ing on the ground, then ascend a reed,
place herself in an inverted position,
with the abdomen inclined a little for-
ward, and thus motionless to await the
coming of the male. Epactiothynnus
females had the same habit awaiting
their mates in a conspicuous place.
The circling males sometimes betrayed
her whereabouts; as soon as located she
was immediately seized and carried
off.
Australia has perhaps the richest
fauna of Scarabeid beetles in the
world, so it is not surprising that the
enemies of these often destructive in-
sects are similarly numerous. The
immense Thynnid population of sev-
eral hundred species far outnumbers
the Scoliidse, and it may be affirmed




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162 Psyche [December
with some degree of certitude that, like the latter, they prey essentially on Lamellicorn beetle grubs. The rather anomalous
"blue ant," Diamnza bicolor, is somewhat related to the Methoca group, and being a fierce and active insect of good size perhaps attacks caraboid beetle larvse.
a
AN AFRICAN FIGITIDB.
BY ALFRED C. KINSEY,
Bussey Institution, Harvard University.
Aspicera africana sp. nov.
Male and Female. Body entirely black, except the antennae and legs, which are rufous-brown. Head: black, ocelli yellowish, compound eyes silvery; front concave, coriaceous, with a few, short, wavy lines, bounded laterally by prominent ridges extend- ing from the lateral ocelli to the base of the antennae and beyond half way to the mouth; lower half of face irregularly rugosostriate, hairy; cheeks hairy; mandibles dark rufous; antennae rufous- '
brown, darker toward the tips, in the ? 13-jointed, in the 8 14- jointed. Thorax: entirely black, finely coriaceous, the sides of the pronotum and the metapleure dense with white hairs; meso- pleurae with a large shining area; parapsidal grooves continuous, deep, cross-ridged, broad at the scutellum, curved sharply apart at the pronotum; a narrow, elevated median ridge extending from the pronotum half way to the scutellum; the depressed median groove from that point to the scutellum is two-thirds as wide as the distance between parapsidals; anterior parallel lines smooth, elevated, extending half the length of the thorax; fovese very large, very deep, sparsely striate, with a fine, shallow ridge between; the spine of the scutellum about half the length of the whole scutellum, with 3 to 5 longitudinal ridges. Abdomen: piceous black, finely and regularly punctate, the 2nd segment dorsally about one- third the total length and reduced to a mere scale on the sides, 3rd segment reaching almost to the tip of the abdomen; abdomen in the male similar but more slender. Legs: uniformly rufous- brown, including the coxae; with short hairs. Wings: very clear,
without hairs; the subcosta, basal vein, and radius distinct, pale



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