Ptychoptera (Paraptychoptera) castor Keresztes & Kappert, 2021

Keresztes, Lujza, Kappert, Juergen, Henning, Maria & Toeroek, Edina, 2021, Helen's twins in the Balkans: discovery of two new Paraptychoptera Tonnoir, 1919 species closely related to P. helena Peus, 1958, with systematic revision of the " lacustris " group (Diptera, Ptychopteridae), ZooKeys 1071, pp. 63-81 : 63

Ptychoptera (Paraptychoptera) castor Keresztes & Kappert sp. nov.

Figure 2

Type material.

Holotype. male, Albania: Tragjas municipality, Rrepet e Izvorit, Vlora district, sweeping the vegetation near a limnocren karst spring with large basin and muddy shore with reeds, 30.iv, 2019, 17 m, leg. M. Henning, 40.323132°N, 19.510031°E. Institutional id for specimen is DCFBG-PT-0002.

Diagnosis

. Ptychoptera (Paraptychoptera) castor sp. nov. is known only from a single male collected near a limnocrene karst spring with muddy shore invaded by rich vegetation at Repet y Izvorit, Tragjas, Albania (Fig. 3 ). Male general habitus, wing venation and spots are highly similar to P. helena (Fig. 4a, b, c ). However, the male epandrium has a unique design, differentiated from all other members of Paraptychoptera , but close to P. helena (Fig. 4d, e ). In contrast to P. helena , the finger-like subapical process on its ventral side is well developed, with a basal chitinous process, equal in length with subapical lobe, which is much shorter in P. helena (Fig. 2d ) and the conspicuous long harpoon-shaped apex of the hypoproct (Fig. 2c ) which is bilobate in P. helena (Fig. 4d ). Gonostylus apical stylus is long, twice as long as the secondary lobe (Fig. 2e ), which differentiates it well from P. helena , where such a process is subequal. Gonostylus anterior lobule with a short finger-like vental process (Fig. 2f ), while in P. helena such a process is much longer and curved at tip (Fig. 4g ). Hypandrium apex lacking a narrow-lobe-like terminal division (Fig. 2g ) which is present in P. helena (Fig. 4h ), and well developed in all other Paraptychoptera species, in addition with a series of fine differences in male aedeagal complex and paramere (Fig. 2h, i ).

Description

. Medium-sized species, body length 7.3 mm, wing length 8 mm. Head and thorax shiny black, almost glabrous, pleuron almost uniformly brownish, some obvious pale setae only above halter. Head shiny brownish, labrum pale brownish to yellow. Antennae with 15 segments. Scape elongate cylinder, pedicel globular, yellowish, as the half of the first flagellar segment. Remainder flagellomeres blackish brown (Fig. 2a ). First flagellar segment shorter than the following two segments together, the others successively shorter and thinner. Each flagellar segment with several long straight black setae and dense pelt of short dark hairs. Eye large, finely faceted, bare; no ocelli. Large, oval, clypeus, convex, terminal labrum yellowish. Large labellum, very long maxillary palpus with whip-like fifth segment pale yellow.

Thorax dorsally black with metallic blue shining, narrow pronotum, base of postnotum and large parts of episternum, epimeron, and metapleuron pale brownish. Coxae and legs yellowish, apex of femur, narrow base and apex of tibia, tarsal segments brownish. Wing with three transverse bands of well-developed confluent dark spots close to anterior margin on basal, middle and distal part of otherwise clear or pale yellowish membrane. Additionally, isolated dark spots are present on both sides of the middle dark band at the level of Sc and at the distal end of R3 (Fig. 2b ). Wing membrane with macrotrichia. Prehalter and halter pale yellow.

First abdominal tergite blackish to dark brown with metallic shining, only a narrow yellow stripe near the distal, tergite 2 large part yellowish with brown spot in the middle, distal part shiny black, tergite 3 brownish, tergite 4 and all distal tergites brownish black. Genitalia pale brown. Narrow sternites pale brown at base, becoming yellowish towards the auxiliary sexual organ on segment III. Sternites 4-7 medially reduced to a narrow band with a deep notch in the middle at proximal margins.

Auxiliary sexual organ less developed than in the other members of Paraptychoptera , excepting P. lacustris and P. helena . Sternite 3 with thin long golden hair fringes on sides; its bare middle part lacking the transversally sculptured median sclerite, but distal brownish patch is present at distal end, close to the deep pouch of the auxiliary sexual organ. Distally sternite 3 with deep pouch of the auxiliary sexual organ. Two caudal lips of the pouch less developed, one smooth lateral lobe on each side, covered with dense hair fringe in their interior part. Lateral lips separated by a deep furrow leading to a small oval sclerite inside the pouch and two lateral lobes covered with fine sculptures.

Male terminalia. Epandrium with distinct collar, deeply and widely emarginated behind, hypoproct long lobe-like and densely hairy (Fig. 2c ). Hypoproct lobe harpoon shaped, tapering at apex. Epandrium lobes long, slightly widened apically. Subapical process of epandrium with a finger-like ventral projection with basal thorn equal in length with the digitiform process (Fig. 2d ). Apex of subapical lobe with long macrotrichia (Fig. 2d ). Gonocoxite simple, with its medial appendage as a simple curved pilose lobe. Gonostylus apical lobe short, finger-like, fringe of setae at apex, secondary lobe similar shape, but twice as long as the apical lobe (Fig. 2e ). Gonostylus anterior lobules divided into a dorsal triangular process and a ventral part with a short finger-like rostrum. Middle lobe strong sclerotised sickle-like rounded at apex, long fine hairs at tip (Fig. 2f ). Hypandrium wide, hemispherical, long, elongate crests in the middle, including a narrow slit between them, from which the eversible sac protrudes. The transverse scale at the base of the slit is less developed, tongue-like, rounded apically, membranous and densely pilose. Hypandrium apex terminal division process missing (Fig. 2g ). Aedeagal complex highly similar to other Paraptychoptera species. Paramere lateral arms well developed, widened towards a sloping apex. Well-developed setae close to the apex of the paramere arms. Apical processes of paramere well developed, rounded, with a recurring thorn-like formation (Fig. 2h ). Apex of aedeagus blunt, depressed medially, subapical lobe of aedeagus pointed (Fig. 2i ).

Female unknown.

Etymology

. The specific epithet is named after Castor, a god from Greek mythology, the twin brother of Helena, because of its close morphological similarity with P. helena .

Figures

Figure 2. Ptychoptera castor sp. nov. a flagellum of antennae b right wing c epandrium, dorsal d subapical lobe of epandrium, ventral e left gonocoxite with gonocoxite lobes f anterior and medial lobules, details g hypandrium, caudal h paramere, ventral i aedeagal complex, dorsal.

Figure 3. Habitat of Ptychoptera castor sp. nov., south-western Albania, Tragjas, Repet y Izvorit.

Figure 4. Ptychoptera helena, paratype male (ZFMK) a habitus male b head and thorax dorsal c right wing d epandrium, dorsal e subapical lobe of epandrium, ventral f gonocoxite and gonostylus complex, dorsal g gonostylus anterior and medial lobules, caudal h hypandrium, caudal i paramere, ventral j aedeagal complex, dorsal.