Porricondyla bidentula, Jaschhof & Jaschhof, 2020

Jaschhof, Mathias & Jaschhof, Catrin, 2020, The Porricondylini (Diptera: Cecidomyiidae: Porricondylinae) of Sweden revisited: descriptions of nineteen new species of ten genera, including a new genus, Zootaxa 4728 (2), pp. 151-182 : 168

Porricondyla bidentula sp. nov.

Figs 30–31

Diagnosis. This is a medium-size Porricondyla with yellowish thorax and evenly gray abdomen, the latter resulting from the unusually uniform sclerotization / pigmentation of both tergites and sternites. Porricondyla bidentula is peculiar for having two gonostylar teeth, a large one ventroapically and a much smaller one dorsoapically ( Fig. 31 , ↓ 1). (The left gonostylus of the holotype, which is the only specimen known of this species, has actually two teeth of even smaller size dorsally.) The shape of the gonostylus is unusual in that its front is flattened, which, viewed from ventrally, results in a conspicuously blunt-ended, somewhat angular outline ( Fig. 31 , ↓ 2). Females and larvae of this new species are unknown.

Other male characters. Body size 1.8 mm. Head. Eye bridge 6–7 ommatidia long at vertex.Antenna with only 4 flagellomeres retained. Scape and pedicel lighter than flagellum. Neck of fourth flagellomere 1.9 times as long as node ( Fig. 30 ). Palpus 1.4 times as long as head height, 4 setose, subcylindrical segments, apical segment longest of all. Thorax. No scutal windows. Pronotum with 5 setae; anepisternum with 3 setae; anepimeron with 5 setae. Wing markedly longer than body. Length / width ratio 3.0. M 1+2 absent. Hind fork incomplete. Legs. Femur and tibia of foreleg nearly equally long. Tarsi and acropods not retained. Genitalia ( Fig. 31 ). Gonocoxal synsclerite: setae confined to ventrolateral and dorsal portions; a pair of interior, sclerotized rims ventrosubbasally; ventral emargination indistinct, its space filled with a vaguely delineated membrane that possibly is homologous with the gonocoxal processes; ventroanterior edge straight; dorsal apodemes long, ending at same level with ventroanterior edge. Gonostylus with conspicuously large setae. Parameres slender, posterior portions running parallel to each other, apices slightly overlapping, pointing dorsomedially. Aedeagal apodeme longer than gonocoxae, slightly broadened on apical third, apex pointed and bent ventrally. Ducts of accessory glands well discernible.

Etymology. The Latin adjective bidentula means ̒with two small teeth’, with reference to the peculiar gonosty- lar armature found in this species.

Type material. Holotype. Male , Sweden, Öland , Mörbylånga , Gamla Skogsby (Kalkstad), scrubby meadow (̒diversity meadow’), 15 August–6 September 2006, Malaise trap, Swedish Malaise Trap Project (trap 22, collecting event 1829) (spn. CEC 2269 in NHRS).

Remarks on the classification. Porricondyla bidentula and P. armata (see Jaschhof & Jaschhof 2013: fig. 97) share several characters that are unknown from other Porricondyla , notably the gonostylus equipped with more than one tooth, largely reduced gonocoxal processes, and the apex of the aedeagal apodeme bent ventrad. We rate this as indicators of close relationship. Porricondyla armata was previously classified in species group A, containing Porricondyla whose gonostylar apex bears a pectinate claw; this needs to be revised here. As described earlier ( Jaschhof & Jaschhof 2013: 211 and fig. 97), the spines building the gonostylar claw of P. armata are markedly stronger than those found in other Porricondyla and therefore may be regarded as several, individual teeth arranged in a line. Following this argument, P. armata and P. bidentula conform in having two or more gonostylar teeth rather than only one single tooth, which is the reason here to classify both in a group of their own (group D in our scheme introduced in 2013).

Figures

FIGURES 30–33. Male morphology of Porricondyla bidentula (30–31) and Porricondyla diversicornis (32–33), holotypes. 30: Fourth flagellomere, lateral. 31: Genitalia, ventral. 32: Genitalia, ventral. 33: Fourth flagellomere, lateral. Scales 0.05 mm. Arrows refer to characters described in the diagnoses.