Drusus iani Ibrahimi, Hlebec, Vitecek & Kučinić, 2025

Drusus iani Ibrahimi, Hlebec, Vitecek & Kučinić sp. nov.

( Figs 3-11 View FIGURES 3-7 View FIGURES 8-11 )

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Type material. Holotype (male): Iran, East Azerbaijan, Sabalan Mouontain, Gurgur River , 38.16994°N, 47.90193°E, 2443 m above sea level, 02.viii.2021, leg. H. Ibrahimi. GoogleMaps Paratype ( 1 male) and Allotype (female): with the same label data as holotype.

Distribution. Iran, Ardabil Province, Sabalan Mountains.

Diagnosis. The male of the new species is most similar to that of Drusus aranos Oláh 2017 (known from Teberda, Russia) and Drusus iranicus Oláh & Chvojka 2017 (known from Central Elburz, Iran) (both in Oláh et al. 2017), but differs by exhibiting (1) superior appendages with acute, pinched, apicodorsally pointed apex, in lateral view; (2) segment IX in lateral view with an acuminate dorsal portion and longer ventral portion, laterally even longer, with expressed triangular median protuberances on anterior and posterior margins in lateral view; 3) rather short inferior appendages, with narrow, tapering apex in lateral view; 4) large, rounded tips of intermediate appendages in lateral view, long and ovate in caudal view, subquadratic with narrow base and wide apex in dorsal view; (5) a short, T-shaped spinulose zone of segment VIII, with long lateral arms and concave apex in dorsal view; 6) a robust and long principal spine on each paramere and one or two small joint secondary spines also projecting ventrad.

The male of Drusus aranos is characterized by (1) superior appendages with apicodorsally rounded apex in lateral view; (2) segment IX with an acuminate dorsal portion and longer ventral portion, laterally even longer, and sinuate anterior margin without an expressed median triangular protuberance in lateral view; (3) moderately long inferior appendages, with wide, rounded apex in lateral view; (4) small rounded tips of intermediate appendages in lateral and caudal views, quadratic with equally long base and apex in dorsal view; (5) a short T-shaped spinulose zone of segment VIII, with short lateral arms and convex apex in dorsal view; (6) a medium-long principal spine of each paramere and several small secondary spines.

The Drusus iranicus male has:1) superior appendages with a rounded apicodorsally apex, projecting dorsad; (2) segment IX with an acuminate dorsal portion and longer ventral portion, laterally even longer and convex anterior margin without an expressed median triangular protuberance in lateral view; (3) rather long inferior appendages with wide, rounded apex in lateral view; (4) large, truncated tips of intermediate appendages in lateral view, long and subtriangular in caudal view, ovate with longer base and shorter apex in dorsal view; (5) a long subrectangular spinulose zone of segment VIII with long apex and short base in dorsal view; (6) a small principal spine of each paramere and few minute, small secondary spines.

The female of the new species is most similar to that of Drusus aranos , Drusus polur Oláh 2017 (known from Polour, Iran) and Drusus simplex Martynov 1927 (known from Verchnij Sadon, Russia) and differs in exhibiting (1) vulvar scale shorter than supragenital plate, both shorter than segment X in lateral view; (2) supragenital plate slightly longer ventrally than dorsally, caudal margin straight in lateral view; (3) lateral lobe of segment IX with wide base in lateral view.

The Drusus aranos female has (1) segment X and vulvar scale almost equally long, supragenital plate slightly shorter in lateral view; (2) supragenital plate longer dorsally than ventrally, caudal margin incised in lateral view; (3) lateral lobe of segment IX rounded in lateral view.

The Drusus polur female has (1) segment X, supragenital plate and vulvar scale almost equally long; (2) supragenital plate longer dorsally than ventrally, apical margin straight in lateral view; (3) lateral lobe of segment IX with narrow base in lateral view.

The Drusus simplex female has (1) supragenital plate and vulvar scale slightly shorter than segment X in lateral view; (2) supragenital plate longer dorsally than ventrally, apical margin medially incised in lateral view; (3) lateral lobe of segment IX with wide base, longer dorsally than ventrally in lateral view.

In addition to this, the female of Drusus iani sp. nov., is easily distinguishable from all other described species of the Drusus simplex Species Complex by its slender, slightly widening apically median lobe of the vulvar scale in ventral view. Such a slender median lobe of the vulvar scale is only present in Drusus polur , but in the latter species it is of equal width along its entire length, and all three lobes of the vulvar scale appear longer than in D. iani sp. nov. In all other described species of the Drusus simplex Species Complex, the median lobe is strikingly triangular, tapering apically in ventral view. Vaginal sclerite of Drusus iani sp. nov. appears basally wider than any of the described females in the Drusus simplex Species Complex in dorsal view.

Description. Habitus brownish yellow, sclerites and tergites light brown; cephalic and thoracic setal areas pale yellow; cephalic, thoracic and abdominal setation yellow, legs brown to yellow, few darker areas proximally; wings yellowish-brown, translucent, with yellow setae. Maxillary palp 3-segmented. Length of forewing 12 -12.3 mm (n=3). Spur formula 1,3,3.

Male genitalia. Tergite VIII subquandrangular, light brown; in lateral view, truncate anteroventrally; in dorsal view, discrete incision anteriorly, two large membranous areas on either side of the spinulose area, darker patches medially and around membranous areas, few setae laterally, narrower posteriorly, T-shaped spinate area posteromedially, spines more abundant apically, scattered towards the base. Segment IX elongate dorsoventrally; in lateral view with narrow, acuminate dorsal portion, enlarged, subquadrate ventral portion, acute projections anteriorly and posteriorly. Superior appendages elongate, covered with fine setae of medium length; in lateral view subrectangular, pointed dorsoapically, ventral margin shorter than dorsal margin, both sinuate; in dorsal view, subovate. Intermediate appendages in lateral view with large, rounded black tips; in caudal view elongated, ovate, and diverging. Inferior appendages in lateral view subtriangular with wide base and tapering apex; long, with rounded apex; in ventral view. Phallic apparatus consisting of simple long aedeagus and pair of parameres; parameres slender, with principal spine long and triangular, two discrete secondary spines, half the length of principal spine, triangular terminal part long and slightly inflated before acute apex.

Female genitalia. Segment VIII subquadrate, setose, in lateral view; in dorsal view equally wide along entire height, setation concentrated mediolaterally. Lateral lobe of segment IX in lateral view, subtriangular membranous, elongated, with longer ventral edge, few setae on dorsal half; in ventral view, subovate. Segment X elongated; in lateral view, triangular, longer than supragenital plate; in dorsal view, wide proximally, slightly narrowing distally, with 2 lateral triangular lobes, setose, and a deep triangular median excision. Supragenital plate quadrate; in lateral view, with rounded posteroventral projection; in ventral view, quadrate, with wide base and slightly narrowing distally. Vulvar scale subtriangular in lateral view, shorter than supragenital plate, with wide tip and concave ventral margin; with 3 lobes in ventral view, lateral lobes elongate, with converging rounded tips, the median lobe slender, shorter than lateral lobes.

Larva, pupa. Unknown.

Etymology. The species epithet is dedicated and refers to the first author’s son, Ian.

Habitat. The new species was collected from the upper reaches of the Gurgur River. The riverbed at the sampling site consisted of stones of various sizes, interspersed with pebbles, gravel, and patches of fine sediment. Riparian vegetation was moderately developed, covering approximately 30% of the stream banks on either side, creating a relatively shaded environment. Although the site appeared to be largely natural, there were signs of mild anthropogenic disturbance in the surrounding area, primarily due to structures and activities related to livestock farming.