Porricondyla gemina, 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 : 170-172

Porricondyla gemina sp. nov.

Figs 34–36

This new species is separated here from P. nigripennis , a common and widespread Porricondyla that Panelius (1965) redescribed on the basis of the type female from France and several male specimens from museums in England, Sweden, Finland, and Italy. We did not restudy Panelius’s (1965) material, so have to leave it open here whether all his specimens are conspecific. His female description does not make clear how P. nigripennis can be distinguished from other Porricondyla , and his male description is not detailed enough to allow one to decide whether it refers to P. nigripennis as defined here, or to P. gemina , or to yet another species of the nigripennis complex, or to a species mix. The definition given here of P. nigripennis (see Diagnosis) is based on male characters determined through examination of 28 specimens from Sweden, Germany and Slovakia. We regard it as unlikely that females that belong to different species of the nigripennis complex can be distinguished from each other using morphological indicators.

Diagnosis. Porricondyla gemina shows the same pattern of scutal windows previously thought to be characteristic of P. nigripennis ( Jaschhof & Jaschhof 2013: fig. 16C). While the female of P. gemina is unknown, we expect that both sexes have scutal windows of identical outline. Males of P. gemina can be distinguished from those of P. nigripennis by genitalic characters. In P. gemina , the gonostylar claw follows the curve of the gonostylar body, i.e. is evenly rounded ( Fig. 34 , ↓ 1), while in P. nigripennis the claw has a dent in the middle, which results in a sinuous edge ( Fig. 37 , ↓ 2). Also, P. gemina shows a more or less conspicuous, bright space between gonostylar claw and body ( Fig. 34 , ↓ 3), which is less obvious or absent in P. nigripennis . As for the gonocoxal synsclerite ( Fig. 35 ), in P. gemina the ventral emargination is small and barely reinforced; the processes, which are tapered apically, have a smooth surface (↓ 4); and the narrowed ventrobasal portion is short (↓ 5); in P. nigripennis the ventral emargination is larger and broadly reinforced by sclerotization; the processes, which are slightly broadened apically, are irregularly wrinkled and, to various extents, covered by what looks like tiny spikes ( Fig. 38 , ↓ 6); and the narrowed ventrobasal portion is longer (↓ 7).

Other male characters. Body size 1.8–2.3 mm. Head. Eye bridge 4–5 ommatidia long at vertex. Antenna clearly longer than body. Scape and pedicel concolorous with flagellum. Circumfila on all flagellomeres. Neck of fourth flagellomere 1.5–1.7 times as long as node ( Fig. 36 ). Palpus 1.6 times as long as head height, 4 setose, subcylindrical segments, apical segment longest of all. Thorax. Pronotum with 4–8 setae; anepisternum with 2–7 setae; anepimeron with 3–6 setae. Wing markedly longer than body. Length / width ratio 2.7–3.1. Venation as in P. nigripennis ( Jaschhof & Jaschhof 2013: fig. 100B). Legs. Foreleg: femur and tibia nearly equally long, tibia 1.2–1.3 times as long as T 2. Abdomen. Sclerotization pattern as in P. nigripennis ( Jaschhof & Jaschhof 2013: fig. 16B). Genitalia ( Fig. 35 ). Gonocoxal setae strictly confined to ventrolateral and dorsal portions, a large area ventromedially devoid of setae (in P. nigripennis , the distribution of ventral setae is more variable and occasionally extends further medially compared with P. gemina ). Otherwise similar to P. nigripennis ( Fig. 38 ).

Etymology. The Latin adjective gemina means ̒as similar as a twin’, an allusion to the close resemblance of this new species to P. nigripennis .

Type material. Holotype. Male, Sweden, Blekinge, Ronneby, Tromtö , Tromtö nabb, mixed forest of beech and oak, 3–16 June 2005, Malaise trap, Swedish Malaise Trap Project (trap 23, collecting event 1477) (spn. CEC 2255 in NHRS) . Paratypes. 1 male, same data as the holotype (spn. CEC 2256 in NHRS) ; 3 males, same data but 15–23 September 2004 (collecting event 1016) (spns CEC2257 – CEC 2259 in SDEI) .

Other material. Sweden: 2 males, Öland, Mörbylånga , Färjestaden, backyard with grove of young birch trees and scrub, 6 March–5 May 2015, MT, MCJ (spns CEC2260 – CEC 2261 in SDEI) ; 2 males, Småland , Nybro, Bäckebo, Grytsjön NR, hay meadow surrounded by hemiboreal taiga, 4–19 June 2005, MT, SMTP (trap 1001, collecting event 1329) (spns CEC 2262–2263 in NHRS) ; 1 male, Södermanland, Tyresö, Åva, Spirudden, oak forest near coast, 28 May–16 June 2004, MT, SMTP (trap 1, collecting event 316) (spn. CEC 2264 in NHRS) ; 1 male. Södermanland, Södertälje, Tullgarns näs, Rävsalaviken, mixed forest near pasture, 23 July–1 August 2003, MT, SMTP (trap 30, collecting event 5003) ; 2 males, Dalarna, Säter, Säterdalen , Näsåkerspussen, alder wood ravine, 18–31 May 2005, MT, SMTP (trap 10, collecting event 1621) (spns CEC2266 – CEC 2267 in NHRS) ; 1 male, Lule Lappmark, Jokkmokk, Vuollerim, backyard, 2 August–1 September 2016, MT, MCJ & M. Karström.

Remark on the occurrence. Porricondyla gemina and P. nigripennis have on various occasions been found co-occurring at one and the same sites.

Figures

FIGURES 34–39. Male morphology of Porricondyla gemina (34–36) and Porricondyla nigripennis (37–39). 34: Gonostylus, ventral, holotype. 35: Genitalia, ventral, holotype. 36: Fourth flagellomere, lateral, holotype. 37: Gonostylus, ventral, specimen from Germany. 38: Genitalia, ventral, specimen from Germany. 39: Fourth flagellomere, lateral, specimen from Germany. Scales 0.05 mm. Arrows refer to characters described in the diagnosis.