Taxonomic notes of Hemixantha (Diptera: Richardiidae) with description of a new species from the Amazon Region

Richardiidae is represented by ca. 180 species in 33 genera. A new species of Hemixantha, now totaling 20 species, is described from the Amazon Region, state of Para, Brazil, and from Teoponte, Bolivia. Hemixantha maculosa sp. nov., H. picta Hennig, 1937 and H. pulchripennis Hendel, 1911 are richardiids known to have an extensively banded wing pattern. Hemixantha maculosa sp. nov. represents the first record of Hemixantha from the state of Para and this species can be distinguished from H. picta and H. pulchripennis by anepisternum and dorsal half of anepimeron bright yellow and vein R2+3 slightly sinuous. Besides the hyaline areas on the wing of H. maculosa are very distinct from these other species, as follows: (1) subtrapezoidal median area in cell cua(1) extended anteriorly to vein M-1, separated from hyaline area in cell dm; (2) two oblique areas from costal margin almost to or beyond vein R4+5, one proximal to and one distal to level of crossvein r-m; (3) a circular area on basal part of cell r(4+5) and (4) a triangular area on basal region of cell m(1). An identification key, diagnoses, description and redescriptions, and illustrations to the species of Hemixantha with an extensively banded wing pattern are provided.