Chrysotoxum Explained

thumbnail|right|Female Chrysotoxum bicinctumThe genus Chrysotoxum (Meigen, 1803) 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 (sides of the thorax).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.[1] Larvae are specialized in preying upon root aphids associated with ant nests.[2] [3]

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 (contacting each other medially) 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 (flagellum) 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.[4]

Species

Notes and References

  1. Shannon . Raymond Corbett . Review of the American xylotine syrphid-flies . Proceedings of the United States National Museum . 1926 . 69 . (9)[2635] . 1–52 . 10.5479/si.00963801.69-2637.1 . 19 July 2021.
  2. Rotheray . Graham . 1998 . Phylogeny of Palaearctic Syrphidae (Diptera): evidence from larval stages . Zoological Journal of the Linnean Society . 127 . 1–112 . 10.1111/j.1096-3642.1999.tb01305.x .
  3. Book: Stubbs, Alan E. . Falk, Steven J.. 1983 . British Hoverflies: An Illustrated Identification Guide. 253, xvpp . British Entomological & Natural History Society.
  4. Masetti . Antonio . Luchetti . Andrea . Sommaggio . Daniele . 2006 . Phylogeny of Chrysotoxum species (Diptera: Syrphidae) inferred from morphological and molecular characters . Eur. J. Entomol. . 103 . 2 . 459–467 . 10.14411/EJE.2006.059 . 55348395 . free .
  5. Violovitsh. N. A.. New species of hover-flies of the genus Chrysotoxum Mb. (Diptera, Syrphidae) from Palaearctic.. Ent. Obozr.. 1973. 52. 924–934.
  6. Book: Walker. F.. List of the specimens of dipterous insects in the collection of the British Museum. Part III. 1849. British Museum (Natural History). London. 485–687.
  7. Book: Vockeroth, J.R. . 1991. The Flower Flies of the Subfamily Syrphinae of Canada, Alaska and Greenland . 456 . Agriculture Canada. The Insects and Arachnids of Canada Part 18.
  8. Williston . S.W. . Synopsis of the North American Syrphidae . Bulletin of the United States National Museum . 1887 . 31 . 1–335 .
  9. Mutin . V.A. . 1999 . Fam. Syrphidae . Key to the Insects of Russian Far East. . 6 . 342–500 .