Laishania, Kung & Brown, 2005

Kung, Giar-Ann & Brown, Brian V., 2005, Three unusually divergent new genera of phorid flies (Diptera: Phoridae) from Costa Rica, Zootaxa 1019 (1), pp. 43-52 : 47

Laishania new genus

Diagnosis. Entire body with short, sparse setae ( Fig. 3 ). Head elongate, rounded. Median furrow of frons absent. Frontal setae present but reduced in size. Eye reduced; ocelli absent. Flagellomere 1 slightly pointed, arista apical. Mouthparts relatively small, unmodified. Thoracic segmentation greatly reduced; scutellum absent. Legs greatly elongate, without large isolated setae; tibiae lacking setae palisades. Forefemur with triangular ventral expansion at midlength; foretibia apically expanded; foretarsomere 1 basally expanded with long fringe of orange setae. Wing and halter absent. Abdomen with well­developed tergites; ovipositor mostly membranous, non­parasitic.

This distinctive apterous species does not resemble any other New World phorid. It is easily recognized by its overall elongate appearance, extremely long legs, and the presence of thin scattered setae across the body. The long legs indicate a possible cursorial lifestyle, and it is likely that this species is an associate of army ants ( Hymenoptera : Formicidae : Ecitonininae).

Laishania does not key out using Disney’s 1994 key to genera of females. This species does not fit either lead in couplet 32, so following his note, one must “proceed to couplet 40.” Following couplet 40, Laishania keys closest to Puliciphora in couplet 46, although it lacks the “bristle, sometimes on a distinct papilla, on side of thorax towards rear,” which is the second character for Puliciphora in that lead. However this genus differs from Puliciphora by the larger size, much longer and modified legs (especially the foretibia), the unusual body setation, the shape of the head and thorax, and the structure of abdominal tergite 7.

Dr. R. H. L. Disney, a helpful reviewer of this paper, suggested that Laishania should not be considered a new genus, and instead should be placed as an aberrant Puliciphora . We disagree with this suggestion. Although Disney has recently made great progress in Puliciphora taxonomy, there are still no apomorphic characters available to define the group; thus, recognizing species of Puliciphora , especially highly divergent ones, based on anything other than overall similarity, is extremely problematic. Our new genus has a number of differences from described species of Puliciphora , summarized above, creating a gap between it and Puliciphora that is at least as great as that between other phorid genera. Until much further information is available for Metopina ­group genera, in the form of currently undescribed males or in molecular characters, there will be considerable uncertainty to generic assignments. We prefer to recognize our distinctive new taxon at the genus level, and not to associate it with a much larger and better­known genus with which it might share little relationship.

Figures

FIGURES 1–3. Laciniomyia dilata new species. 1. Abdomen, dorsal. 2. Body, lateral. 3. Laishania angustithorax new species. Body, lateral.