Aeschrocorini Distant, 1902: "A division at present represented only by two genera in this fauna and marked by very distinctive characters. The head is long, with the lateral lobes much longer than the central; the pronotal angles are very prominently dilated; the scutellum is broad and short; the membrane has the veins more or less reticulate and does not reach the apex of the abdomen." Linnavuori, 1982: Under the heading The Tyoma group: Linnavouri includes Aeschrus in his discussion of this group in several places, and although he indicates that Aeschrus is very distinctive and "forms a group of its own," he still includes it in the key to Tyoma group genera. My comments: I have examined specimens of Aeschrocoris, Aeschrus, Geomorpha, and Tyoma. At present, I believe that Aeschrocoris, Geomorpha, and Tyoma all belong to a single tribe. Aeschrus, as noted by Linnavuori, 1982 (see above), is quite different, and may not belong in this tribe. Important defining characters of the Aeschrocorini include all three thoracic sterna very sulcate, the spiracles are very lateral in position located just below the lateral margin of the abdomen, between each spiracle are tubercles variously produced, and the trichobothria are posterior and distinctly mediad of each corresponding spiracle. A character of possible lesser importance is that the venation of the forewing is usually reticulate. It appears that Cachan’s Chraesus and Schouteden’s Risbecella are also definitely members of this tribe. Although I have not examined specimens, I have serious doubts about including Scylax and Tyomana in this tribe. Scylax is described as having the mesosternum medially carinate. Tyomana has the wing venation "regular," and there are no tubercles along the lateral margins of the abdomen. Aeschrus does look superficially very similar in general appearance to the members of this tribe, but the spiracles are not located laterally, the pronotum has a very distinct rounded flap extending posteriorly on each side over the base of each corium, and the scutellum is expanded laterally beyond the apex of the frenum on each side, also covering part of each corium. One last note: Probably should compare the South American genus Caonabo as it has the spiracles lateral in position with a tubercle between each spiracle along the lateral margins - the mesosternum is medially carinate, however. Included Genera:
Aeschrocoris Bergroth, 1887
David A. Rider updated: 30 Aug 2005 Published by the
Department of
Entomology
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