Asynaptini Rübsaamen & Hedicke

Jaschhof, Mathias & Jaschhof, Catrin, 2019, New and rarely found species of asynaptine Porricondylinae (Diptera: Cecidomyiidae) in northern Europe, Zootaxa 4604 (2), pp. 281-300 : 283

Asynaptini Rübsaamen & Hedicke

Adult Asynaptini differ from other Porricondylinae in that the maxillary protuberance (including stipes and cardo) is enlarged; the number of flagellomeres in both sexes usually exceeds 14 (up to 30 in males, 40 in females); male circumfila lack side branches; abdominal sclerites are subdivided into two or four portions; male gonocoxal processes are either rudimentary ( Asynapta ) or absent (remaining genera); the central genitalic structures, i.e. parameres and aedeagus including ejaculatory apodeme, are closely interconnected to form a complex apparatus referred to as the copulatory organ; and the dorsal lamella of the ovipositor is reduced to only two segments, the basicercus and the disticercus ( Jaschhof & Jaschhof 2013). The construction of the copulatory organ is revisited here, prompted by some authors’ assigning to new genera Camptomyia species with exceptionally odd parameres (see Fedotova & Sidorenko 2005; Fedotova 2018). A central point in our reinterpretation is the assumption of two pairs of parameres, ventral and dorsal, belonging to the basic pattern of asynaptine male genitalia. We further assume that the condition found in Parasynapta Panelius comes closest to the ancestral pattern: two pairs of tusk-shaped parameres bordering the aedeagus whose anterior component is a simple, sclerotized rod (ejaculatory apodeme) and whose posterior component is a more complex, largely membranous extension (aedeagal head) ( Jaschhof & Jaschhof 2013: fig. 178C). The area where the ejaculatory apodeme transitions into the aedeagal head is normally somewhat thickened, marking the site where the pair of ejaculatory gland ducts enter the genital tube. The ends and orifices of those ducts are often slightly reinforced, which makes them better visible, particularly in Camptomyia ( Jaschhof & Jaschhof 2013: fig. 174C). Examining extant Asynaptini in their entirety, it is evident that parameres occur in a wide range of different shapes and varying degrees of connectivity with the aedeagus. The variation found in parameral structure includes the absence of one of the pairs or that both sides of a pair may be entirely or partly merged with each other to form a shield (tegmen). While the construction of the copulatory organ, including the parameres, differs from species to species, the basic design within a genus is to some extent distinctive; those genus-specific patterns are described here in more detail under Asynapta and Camptomyia . In this paper we employ terms for parts of the copulatory organ that differ from previous usage ( Jaschhof & Jaschhof 2013), as follows: ventral parameres (instead of parameres in Asynapta , and parameral processes in Camptomyia ), dorsal parameres (instead of aedeagal head in Asynapta , and parameres in Camptomyia ), aedeagal apodeme (instead of ejaculatory apodeme), and aedeagal apex (instead of aedeagal head) (see Figs 3 and 9 ).

Figures

FIGURES 1–4. Genitalic morphology of Asynapta spp. 1: Gonostylus of A. inflatoides, ventral, paratype. 2: Gonostylus of A. rickebasta, ventral, holotype. 3: Aedeagus and parameres of A. rickebasta, ventral, holotype. 4: Genitalia of A. taigensis, ventral, holotype. Scales for 1–3, 0.025 mm, for 4, 0.05 mm. Arrows refer to characters described in the diagnoses.

FIGURES 5–9. Camptomyia hedmarki, male, holotype. 5: Genitalia, ventral. 6: Apex of gonostylus, ventral. 7: Zoom of central parts of genitalia, ventral. 8: Fourth flagellomere, lateral. 9: Aedeagus and parameres, ventral. Scales for 5, 0.1 mm, for 6, 0.025 mm, for 7–9, 0.05 mm. Arrows refer to characters described in the diagnosis. Abbreviations: dpm = dorsal parameres, vpm = ventral parameres.