Majerthrips, Mound, Laurence A. & Minaei, Kambiz, 2006

Mound, Laurence A. & Minaei, Kambiz, 2006, New fungus­feeding thrips (Thysanoptera Phlaeothripinae) from tropical Australia, Zootaxa 1150, pp. 1-17 : 7

Majerthrips gen. n.

Large polymorphic Phlaeothripinae –Docessissophothripini. Antennae 8­segmented, III with 1 sense cone, IV with 3 sense cones, VII and VIII broadly joined by oblique suture. Head about twice as long as wide, elevated in midline, narrowest just behind compound eyes ( Fig. 10 ); postocular setae capitate; postocellar setae acute in microptera, capitate in aptera; maxillary stylets retracted to compound eyes, close together in midline, maxillary guides stout; mouth cone pointed. Pronotum transverse, four pairs of capitate major setae present, anteromarginals absent (present in aptera); notopleural sutures complete. Mesonotal lateral setae capitate; metanotum reticulate, transverse in aptera; metanotal median setae acute (capitate in aptera). Prosternal basantra absent, ferna varying from pointed to rounded medially ( Fig. 9 ); mesopraesternum complete but eroded, particularly in aptera. Metathoracic sternopleural sutures long and curved ( Fig. 9 ), sometimes reaching almost hind coxal cavity. Both sexes with large fore femora and fore tarsal tooth. Forewings variable in length, also form of sub­basal setae, reaching thoracic hind margin in microptera, reaching tergite II hind margin in hemimacroptera. Pelta variable, quadrate to D­shaped ( Fig. 10 ), but narrowly bell­shaped in aptera ( Fig. 11 ); tergites II–VI each with 2 pairs of sigmoid wing­retaining setae, in microptera these are strongly developed only on III and IV, on VII they are short and straight as on all tergites of aptera; tergites with one pair of capitate posteromarginal setae, aptera with one pair of capitate setae medially ( Fig. 11 ); tergite IX setae S1, S2 and S3 capitate in both sexes. Sternites III–VI of both sexes anterolaterally with areas of specialised reticulation; sternal discal setae small in single transverse row.

Type species Majerthrips barrow i sp.n.

Comments

The type species of this new genus has long maxillary stylets that are about 5microns in width, more slender than those of Idolothripinae species but broader than those of typical Phlaeothripinae . These stylets are very similar in their width, and in their length and position medially within the head, to those found in species of the phlaeothripine tribe Docessissophothripini ( Mound & Palmer, 1983). Moreover, as in most members of that tribe, the pelta is not broad, particularly in apterae, and the males have distinctive iridescent reticulate sculptured areas on sternites III to VII of the abdomen. Two genera of this tribe are known from Australia. Holothrips Karny includes species from around the world, and these have antennal segments VII and VIII more or less fused, and segments III and IV have three and four sense cones respectively. Asemothrips Hood is used for a group of small species, five Australian and one Indonesian, but these have antennal segments III and IV with two and four sense cones respectively. In contrast, the new species described below has segments III and IV with one and three sense cones respectively. All of the species in the Docessissophothripini appear to be fungus feeders on dead plant tissues. This new species is unusual amongst the members of this tribe in exhibiting polymorphism related to wing development as well as sex. The genus is named in recognition of the many contributions of Jonathan Majer to the studies of Australia’s biodiversity.

Figures

FIGURES 9 – 14. Majerthrips and Sennithrips species. (9) M. barrowi micropterous female, ventral; (10) M. barrowi micropterous female, dorsal; (11) M. barrowi apterous female, metanotum and tergites I – II; (12) S. psomus, ventral; (13) S. psomus, dorsal; (14) S. psomus antenna. [ns = prothoracic notopleural suture; ss = metathoracic sternopleural suture]