Myanmarothrips, Ulitzka, 2018

Ulitzka, Manfred R., 2018, A first survey of Cretaceous thrips from Burmese amber including the establishment of a new family of Tubulifera (Insecta: Thysanoptera), Zootaxa 4486 (4), pp. 548-558 : 550-551

Myanmarothrips gen. n.

Type species. Myanmarothrips pankowskiorum sp. n. Diagnosis. Antennae ( Fig. 3) 9-segmented with rings of short microtrichia on all segments; III with a circular sensorium, IV with a small transversely kidney-shaped sensorium; I–III distinctly stronger than distal segments. Fore wings ( Fig. 7) distally narrowed to a softly pointed tip; longitudinal veins complete, with four cross-veins. Wing surface on fore wings covered with microtrichia; hind wings smooth, apart from some sparse microtrichia at extreme tip ( Fig. 8). Head with long postocular setae directed backwards ( Fig. 3). Pronotum studded with regular rows of marginal setae (similar to extant Erotidothrips Priesner ; cf. Mound & O’Neill 1974); one pair of long posteroangular setae present. Fore femora stout in males and females ( Fig. 4); tarsi two-segmented; fore tarsus without a hamus.

Etymology. Named after Myanmar, the amber’s country of origin.

Discussion. Even though the antenna of Myanmarothrips gen. n. is not moniliform (cf. Bhatti 2006), the form of the antennal sensoria, the enlarged fore and hind femora as well as the shape of the wings with pointed tips and their venation characterized by the emergence of vein M distally to the fork RA–RP (cf. Nel et al. 2012) indicate that the new genus is attributable to Merothripidae . Species associated with this family have nine-segmented antennae, apart from members of Merothrips Hood , which have the two terminal segments fused ( Mound & O’Neill 1974). The presence of nine antennal segments is a plesiomorphic character for all Thysanoptera ( Mound et al. 1980) . Merothripidae species are considered to have retained some of the ancestral character states of Thysanoptera , particularly the presence in females of a pair of lobes on the posterior margin of the seventh sternite ( Ulitzka 2015a). These structures are considered to represent a reduced eighth sternite ( Mound et al. 1980), and they are otherwise found only in species of Melanthripidae . In fossils, however, the abdomen is often constricted and thus this feature is hardly visible. In the new species described below it is not assessable.

Myanmarothrips gen. n. differs from Jezzinothrips zur Strassen at least in the shape of the antennae and the presence of microtrichia on the antennal segments. Furthermore, the wing-shape is clearly different (cf. zur Strassen 1973, p. 14, fig. 10). Myanmarothrips gen. n. is unusual in the presence of microtrichia only on the fore wings in contrast to a smooth hind wing membrane.