A contribution to the knowledge of the immature stages of Curtonotum (Diptera: Curtonotidae), from Africa and the Middle East, with a discussion of relationships to other known Ephydroidea larvae

Abstract

The morphology of the puparia of Curtonotum saheliense Tsacas and C. simile Tsacas are described or redescribed, based on material reared from locust egg pods in Mali and Oman, using SEM techniques and light microscopy. The original specimens on which Greathead based his 1958 larval description of C. cuthbertsoni Duda, have been located and examined and are here ascribed to C. simile, rather than C. saheliense as previously assumed, based on examination of the type specimens of both. An additional larva, also reared from locust egg pods in northern Nigeria, is tentatively ascribed to C. saheliense and is described using SEM techniques, despite its relatively poor state of preservation. The two species are shown to be separable based on the relative lengths and widths of the mouthooks and intermediate sclerite of the cephaloskeleton and in the degree of expansion of semi-circular cuticular folding adjacent to the anal opening on the anal pad. A diagnosis of the immature stages of the genus Curtonotum Macquart is provided and the larval and puparial features of C. saheliense and C. simile are compared to the puparium of the Nearctic species C. helvum (Loew), the other species of the genus for which the immature stages are partially known. The composition and homologies of caudal tubules are discussed, as are features in common between the three species under discussion, and tentative comparison is made of the known immature stages of Curtonotum to those of the known larvae of other families of the Ephydroidea, as additional larval features are now discernible for the Curtonotidae. It is concluded that the larval morphology of the Curtonotidae is generally close to the putative groundplan of the Ephydroidea and are probably most closely allied to the Drosophilidae and Camillidae. The relative length of abdominal compartments six and seven is probably an autapomorphy of the family.