The position of the Azeliinae in the Muscidae (Diptera) based on musculature of the male terminalia

The male genital and pregenital skeleton and musculature were studied in males of the following species of the Muscidae subfamily Azeliinae: Drymeia firthiana (Huckett, 1965), Drymeia longiseta Sorokina & Pont, 2015, Drymeia segnis (Holmgren, 1883), Thricops nigritellus (Zetterstedt, 1838), Thricops hirtulus (Zetterstedt, 1838), Hydrotaea dentipes (Fabricius, 1805), Muscina stabulans (Fallén, 1817), and Muscina levida (Harris, 1780). Descriptions and figures of the genital sclerites and muscles of D. firthiana and M. stabulans are given. A comparison was made between the genital segments and muscles of previously studied species of Mydaeinae and Muscinae and those of the Azeliinae. Based on the structure of the skeleton and muscles of syntergosternite VII + VIII and the phallapodeme muscles, significant differences were found between the subfamily Azeliinae and the subfamilies Mydaeinae and Muscinae. The basal position of the Azeliinae within the family Muscidae was confirmed. A comparison of the genital segments and muscles of the Muscidae with those of the Scathophagidae (Scathophaga stercoraria (Linnaeus, 1758)) and Anthomyiidae (Delia platura (Meigen, 1826)) was made. Tendencies in reduction of the pregenital segments and musculature, as well as of the phallapodeme muscles in the evolution of the Muscoidea have been revealed. The complete set of phallapodeme muscles in the Scathophagidae and Anthomyiidae corresponds to the basal state, and therefore the structure of the genital sclerites and muscles in the Muscidae shows a certain degree of reduction. The progressive changes in the Muscidae from the Azeliinae through the Mydaeinae to the Muscinae were traced.

Skeleton and musculature of the male abdomen in Tanyderidae (Diptera, Nematocera) of the Southern Hemisphere

The structure of the male terminalia and their musculature of species of tanyderid genera Araucoderus Alexander, 1929 from Chile and Nothoderus Alexander, 1927 from Tasmania are examined and compared with each other and with published data on the likely relatives. The overall pattern of male terminalia of both genera is similar to those of most Southern Hemisphere genera, with simple curved gonostyli, lobe-like setose parameres, and setose cerci inconspicuous under the epandrium. Both genera have terminalia similarly rotated by 180° (and 90° as an intermediate stage); rotation may be either clockwise or counterclockwise. However, the similar patterns are realized differently: segment VIII is the decreased and asymmetrical due to completely membranose tergite VIII in Nothoderus (the first record of such modification in Tanyderidae), but narrow and symmetrical in Araucoderus. Accordingly, pregenital muscles are very different between the genera. Based on localization of muscle attachment sites, the hypandrial origin of the stripe between gonocoxites is shown in both genera, and entire membranization of tergite VIII and partial membranization of hypoproct is shown in Nothoderus. Tanyderidae are characterized by highly specialized sclerites and muscles of male terminalia and provide no evidence of relationship with previously studied members of Psychodidae, Blephariceridae and Ptychopteridae.

X-ray microtomography (microCT) of male genitalia of Nothybus kuznetsovorum (Nothybidae) and Cothornobata sp. (Micropezidae)

The results of manual dissection of the musculature of the male genitalia in Nothybuskuznetsovorum are fully confirmed by the modern methods of Micro-CT. A comparative analysis of Neriacommutata and Cothornobata sp. shows that an increase in the flexion in the genitalia of males and the displacement of syntergosternite VII to the ventral side in Cothornobata sp. caused the disappearance of the muscles ITM6–7r and ITM7–8r. In addition, this increase in flexion apparently caused the fusion of the M18 muscles into one bundle. The muscle ISM5-6c goes on to moving the second segment of the forcipate appendages of sternite V.

Musculature of the male genitalia in Rivellia (Diptera: Platystomatidae)

The musculature of male genitalia was studied hitherto only in two species of Tephritidae, one species of Platystomatidae, one species of Pallopteridae, and three species of Ulidiidae of the superfamily Tephritoidea. The split of the hypandrium from one structure into three (the hypandrium and two lateral sclerites) is traced. The hypandrial origin of the lateral sclerites of the hypandrial complex is shown based on the localization of muscle attachment sites. The subepandrial origin of the inner lobes of the surstyli is also confirmed.

Description of the larva and biological notes on Vermiophis taihangensis Yang & Chen, 1993 (Diptera: Vermileonidae) from China

Unmixed colonies of larval antlions and wormlions in similar pits were found in the Xiaolongmen National Forest Park in the Taihang Shan, China. A male of Vermiophis taihangensis Yang & Chen, 1993 was reared from a larva and a morphological description of the third instar larval wormlion is presented. The larva of Vermiophis taihangensis differs from the related species V. ganquanensis Yang, 1979 in the well developed sclerotized stigmata on abdominal segment 4, but is similar in the structure of the lateral row of setae and the same number of spines (6) on the pseudopod on the abdominal segment 1.