Akthethrips Mound, 1970

Mound, Laurence A., Tree, Desley J. & Wells, Alice, 2022, Convoluted maxillary stylets among Australian Thysanoptera Phlaeothripinae associated mainly with Casuarinaceae trees, Zootaxa 5190 (3), pp. 301-332 : 315-316

Akthethrips Mound

Akthethrips Mound, 1970: 452 .

Type species Akthethrips strobus Mound , by monotypy.

The single species that is placed in this genus is distinguished from other Phlaeothripinae with convoluted maxillary stylets by the prolongation of the head between the basal antennal segments ( Fig. 40 ). This is particularly obvious in females in which the head is more than 2.5 times as long as wide. However, the head of the available males is much shorter and scarcely 1.5 times as long as wide, and the prolongation is only half as long as the first antennal segment. The presence of one sense cone on antennal segment III and three on IV, also most other character states in the diagnosis, suggest a relationship to the genus Heligmothrips , but the more basal position of the sensorium on antennal segment II is unusual.

Diagnosis. Small brown macropterous Phlaeothripinae with prominent interantennal projection in female. Head about twice as long as wide; large female with interantennal projection extending to apex of antennal I, shorter in male; eyes longer on dorsal than ventral surface; postocular setae well developed in large female and male, reduced in small female; mouth cone short and rounded; maxillary stylets elongate, crossing over each other near base of head, with one lateral convolution; mandible small, restricted to mouth cone. Antennae 8-segmented; segment II with campaniform sensillum placed medially or toward the base; segment III with 1 sense cone, IV with 3 (or 2) sense cones; VIII distinct from VII but not constricted at base. Pronotum narrower than prothorax ( Fig. 41 ), all 5 pairs of major setae present; notopleural sutures complete. Prosternal basantra absent; mesopresternum reduced to two triangles; metathoracic sternopleural sutures long. Mesonotal midlateral setae well developed with apices expanded; metanotum reticulate medially with 1 pair of small fine setae. Fore tarsal tooth larger in female than in male. Fore wing parallel-sided, duplicated cilia present, 3 sub-basal setae present with expanded apices. Pelta elongate triangular ( Fig. 42 ); tergites II–VII with 2 pairs of sigmoid wing-retaining setae arising laterally; tube short with long anal setae; sternites with transverse row of about 10 discal setae; male sternite VIII with no pore plate.

Figures

FIGURES 40–50. Akthethrips, Enigmathrips, Phallothrips, Thaumatothrips. A. strobus 40-42: (40) head; (41) pronotum; (42) metanotum & pelta. E. carnarvoni 43–46: (43) antenna; (44) head; (45) prosternites; (46) pronotum. (47) T. froggatti head & fore legs. P. houstoni 48–50: (48) microptera; (49) macroptera; (50) macroptera tergites V–VII.