Toxomerus Macquart, 1855 belongs to Syrphinae (Syrphidae) and it is the only genus included in Tribe Toxomerini, with approximately 150 species described in the world. It occurs mainly in the Neotropical Region with 143 species, followed by the Neartic Region with 16 species (9 endemic) (Borges and Couri 2009).
The genus Toxomerus is characterized by : eye with distinct triangular emargination on posterior margin; gena narrow; arista bare; postpronotum bare; meron bare; anatergum bare; katatergum bare; posterior spiracle with short pile on margin; metasternum bare; metaepisternum pilose; metaepimeron bare; male genitalia well sclerotized, very short to long postanal process arising from fused surstylar apodemes and projecting caudad between bases of surstyli (Borges and Couri 2009).
Toxomerus politus has face 1/3 as long as eye width, yellow; frontal triangle yellow; proepimeron yellow; scutum black except broadly yellow laterally; scutellum yellow, black pilose; anepimeron anterior and dorsomedial yellow, anepimeron posterior black. Femora and tibiae yellow. Wing extensively microtrichose; alula broader than cell BM appically, microtrichose. Abdomen with 3rd and 4th terga yellow on basal 2/3, with narrow black subbasal fascia connected to medial vitta to form L-shaped macula not touching the lateral margin. Surstylus almost all with the same width; postanal process 1/3 as long as surstylus; aedeagus enlarged, proeminent dorsally and ventrally; superior lobe somewhat rectangular, acuminated dorsally, with hairs in distad anteroventral margin and scattered hairs, with small lobe ventrally with hairs. Female genitalia: 9th tergum with somewhat trapezoid black macula concave posteriorly; epiproct slender; cercus slender; hypoproct as a triangular arch; two elliptical spermatecae similar in size (Borges and Couri 2009).