Cuticular morphology of larval mountain midges (Diptera: Deuterophlebiidae): implications for the phylogenetic relationships of Nematocera
The cuticular structure of larval mountain midges (Diptera: Deuterophlebiidae) is described, with emphasis on cranial and mouthpart morphology. Homologies are suggested for musculature and external features of the head capsule. External morphology of the thorax and abdomen is described, and a system for deuterophlebiid larval chaetotaxy is presented. Also included is a discussion of the feeding behaviour of deuterophlebiid and blepharicerid larvae, and how differing morphological characteristics influence mechanisms of food acquisition. Larval morphology of the Deuterophlebiidae and other Nematocera provides support for (i) a sister-group relationship between the Deuterophlebiidae and Blephariceridae; (ii) a monophyletic Blephariceromorpha (sensu Wood and Borkent) composed of the Nymphomyiidae + (Deuterophlebiidae + Blephariceridae); and (iii) a sister-group relationship between the Blephariceromorpha and Psychodomorpha (sensu Wood and Borkent).