Trypanophion gigas (Diptera: Tephritidae: Trypetinae: Adramini)
Posting an image of Trypanophion gigas is a great way to get back to the flies. It is one of the largest species of true fruit flies, the Tephritidae, in the world. Trypanophion is a monotypical genus (one that contains only a single species), one of the 26 genera in the tribe Adramini, whose members display a wide range of host choice and feeding behaviours, including frugivory (fruit feeding). Others are flower-bud feeders or stem miners. The etymology of the generic name Trypanophion is a bit obscure. In Greek, “trypan” means to bore or pierce through, probably pertaining to the behaviour of trypetine females which use their sharp ovipositor to pierce their plant host to lay egg(s). Also, there is one source online for “phion” that reports an Irish origin for the word, meaning “ruler”. “Gigas” in Latin and Greek means “giant”. So, we have the ruling giant that pierces. I won’t argue with that, as the large size of Trypanophion (our specimen in the image is ca. 13.8 mm long) and its impressive colouration suggest the stature of a mythical queen.
Based on morphological and molecular data Trypanophion is the sister genus of Coelopacidea and both are closely related to the stalk-eyed fruit fly genera (Pelmatops + Pseudopelmatops; (google their images – definitely worth a look!). The plant host of Trypanophion is unknown, but for those willing to use talent and time in search of modest discoveries, a good starting point would be to examine the stems of Senecio, a large genus in the Asteraceae (sunflower) family. Coelopacidia, has been reared from larvae boring in the stems of Senecio species, and Trypanophion may do the same. The larvae of Coelopacidia have also been found boring inside the stems of Polemmania, a genus of Apiaceae (=Umbelliferae, the carrot and parsley family). A further clue to finding Trypanophion may be found in the habitat (upland forest) in which adult Trypanophion have been sampled. All the Kenyan records are from forests west of the Great Rift Valley; Kakamega Forest, Kaberua Forest, and Mt Elgon riverine forest, at 1620, 2052, and 1887 m in elevation, respectively. In addition to Kenya, the species has been found in Uganda, Cameroon, and Zimbabwe.
Credits: Dr Robert Copeland