Chrysotoxum


The genus Chrysotoxum consists of large, wasp-mimicking species. The adults are distinguished by very long antennae, oval abdomen with yellow stripes, and yellow patterns on the thoracic pleurae.
The species of Chrysotoxum are chiefly Holarctic in distribution.
. The species in this genus, are mostly very uniform in structure and colour and are separated with difficulty.
Larvae are specialized in preying upon root aphids associated with ant nests.

Taxonomy

Chrysotoxum is the only genus in the tribe Chrysotoxini
Features common to this genus are:
The head is slightly wider than the thorax. The eyes are more or less pubescent and are contiguous in males and widely separated in females. They have a prominent or angular frons and antennae base, features best seen in profile. The face is slightly concave. The antennae are long and erect, inserted on the frontal angle, with the first two segments nearly equal, and the third one is three to six times longer than the previous ones. Abdomen strongly convex dorsally, very deeply margined. Abdomen strongly convex dorsally, very deeply margined. The wings have the median transverse vein located before the middle of the discal cell. The wing vein R4+5 clearly dipped into cell r4+5.
There are many Chrysotoxum taxonomy concerns yet to be resolved due to the few morphological features available for species characterisation. Characters frequently used: the color of legs, the overall size, the connections between the various abdominal stripes and spots have been found to vary considerably within a species Differences in male terminalia, often of great diagnostic value in other genera are, so far, unhelpful among the majority of Chrysotoxum species.

Species