Curtonotidae

McAlpine, David, 2011, Observations on Antennal Morphology in Diptera, with Particular Reference to the Articular Surfaces between Segments 2 and 3 in the Cyclorrhapha, Records of the Australian Museum 63 (2), pp. 113-166 : 140

The Curtonotidae

The antennae of Axinota pictiventris Wulp ( Figs 76, 78 ) and Cyrtona sp. (Karen, Kenya, Fig. 77 ) are here considered.

In Axinota segment 2 has the rim represented by a double ridge on its medial side. The distal articular surface is concave and more deeply recessed laterally to the conus. The conus is asymmetrical, broad and very short, with the foramen facing laterally. The foraminal ring is crenulate laterally as in Campichoeta , but is not entirely visible in the preparation. Segment 3 has a very marked differentiation into basal stem and distal disc. There is no basal hollow, and the caecum on the basal stem is minute. The basal stem bears the basal foramen on its ventromedial surface not far from its extremity. The arista lacks segment 4; segment 5 is very short and stout, and segment 6 is swollen basally.

The antenna of Cyrtona has a general resemblance to that of Axinota , with a few notable differences. Segment 2 lacks the additional ridge of the rim; the lateral part of the distal articular surface is less narrowly recessed so that the button is readily detected, just laterally to the foraminal ring; segment 3 has a less attenuated basal stem; segment 4 is distinctly sclerotized so that the arista is three-segmented.

Figures

Figures 76–78. Antennae of Curtonotidae. (76) Axinota pictiventris Wulp, left seg. 2, seg. 3 removed, distolateral view. (77) Cyrtona sp., left seg. 2, similar view. (78) A. pictiventris, left seg. 3, medial view. a5, antennal seg. 5; bf, basal foramen of seg. 3; bs, basal stem; bu, pedicellar button; d, disc of seg. 3; sc, sacculus.