Ivanauskiella Ivinskis & Piskunov, 1980

Bidzilya, Oleksiy, Karsholt, Ole & Šumpich, Jan, 2023, A revision of the genus Ivanauskiella (Lepidoptera: Gelechiidae), Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 63 (1), pp. 135-164 : 136-138

Ivanauskiella Ivinskis & Piskunov, 1980

Ivanauskiella Ivinskis & Piskunov, 1980: 23 (original description; type species: Ivanauskiella turkmenica Ivinskis & Piskunov, 1980: 25 , by original designation)

Spatuncusella Nel & Varenne, 2013: 35 (original description; type species: Spatuncusella occitanica Nel & Varenne, 2013: 40 , by original designation). Synonymized by NFL & VARFNNF (2017).

Diagnosis. Ivanauskiella is characterised by clavate valva, narrow elongate sacculus, long clavate uncus and stout phallus with needle-shaped spines in vesica in the male genitalia. Normally double signum with small rounded anterior one and large horned posterior one, in combination with distinct colliculum that usually bears short thorn-shaped sclerites (but see details below) are characteristic for the female genitalia.

Most of these characters are scattered within other genera of Anomologinae : strong uncus is present in Psamathocrita Meyrick, 1925 , slender saber-shaped sacculus, somewhat similar valva, needle-shaped cornuti and distinct colliculum can be found in some Monochroa Heinemann, 1870 , whereas signum with characteristic thorns is common for Oxypteryx Rebel, 1911 and Bryotropha Heinemann, 1870 . However, the unique double signum in combination with the above-mentioned suite of characters unambiguously separates species of Ivanauskiella from other genera of the tribe.

Description. Head smoothly scaled; labial palpus upcurved, long, protruding over head, segment 2 of labial palpus about as broad as or just slightly broader than segment 3, smooth, dark with light apex, segment 3 0.66–0.75 length of segment 2, slender, pointed, uniformly coloured or with indistinct belts; scape of antenna without pecten, flagellum filiform, weakly or distinctly light annulated.

Thorax and tegula concolorous with head. Forewing elongate, moderately slender, wingspan 6.0– 12.5 mm, normally more or less uniformly light grey to light brown and brown, with slight sheen in some species, dark suffusion along margins and termen in some species, pattern (if present) consists of three brown spots in cell, brown spot (or touch) in fold, and additional diffuse small dark spots below costal margin; costal and dorsal margins distinctly lightened in I. albimarginata sp. nov.; hindwing light grey to dark grey, with distinct subapical excavation and slender pointed apex. The venation for I. occitanica is described and illustrated by NFL & VARRFNF (2013).

Frenulum simple in male and consisting of two ( I. limoniella sp. nov.) or three ( I. bovis sp. nov.) acantae in female.

Abdomen. Male segment VIII slightly longer than remaining abdominal segments, sternum subrectangular, tergum trapezoidal, with pairs of hair-like tufts and tufts of grape-shaped coremata arising from membranous connection between posterior margin of segment VIII and genitalia capsule. Female segment VII twice as long as remaining abdominal segments, with row of dense scales along dorsal margin, sternum subquadrate to subrectangular, tergum VII twice as long as broad; sternum II with distinct venulae and well developed apodeme.

Male genitalia. Uncus long, slender with apex strongly flattened laterally, with posterior margin finely serrate, connected with tegumen by distinct basal sclerotised arms; gnathos absent; tegumen as broad as or slightly broader than long, subrectangular, with broad triangular posteromedial and shallow anteromedial emarginations, lateral parts wrapped inside; valva clavate, with narrow medial portion and strongly broadened apex covered with short setae; sacculus direct, weakly bent to saber-shaped, 0.33–0.50× as long as valva; vinculum very short; saccus short, subtriangular or subrectangular; phallus stout, long, parallel-sided, cornuti in vesica vary in number and shape from several comparatively large thorn-shaped to about 20 small, needle-shaped spines, additional group of minute spines gathered in rounded apical plate is usually present, in some species vesica bears numerous minute spines only; lamina ducti ejaculatorii as long as phallus with anterior sclerite.

Female genitalia. Papilla analis subovate, covered with short hair-like setae; apophysis posterioris straight or weakly curved, as long as or slightly longer than apophysis anterioris; segment VIII weakly sclerotised, subtrapezoidal, about as long as broad, slightly narrowing posteriorly, sternum VIII evenly sclerotised except for subtriangular posterior plates, posterior margin straight with row of strong setae; ostium indistinct; apophysis anterioris straight, divided at base into two processes: one of them extending posteriorly towards subtriangular plate under posterior margin of sternum VIII, another one directed dorso-laterally; ductus bursae moderately broad, of equal width or slightly broadened anteriorly, colliculum subtriangular belt, situated at 0.33–0.66 of ductus bursae, part of ductus bursae anteriorly adjacent to colliculum is modified bearing one or two thorn-shaped sclerites, densely covered with short teeth and weakly wrinkled, ductus seminalis arises slightly anteriorly from colliculum (for practical reasons we treat thorn-shaped sclerites as part of colliculum in species descriptions), corpus bursae rounded to ovate, signum usually paired: anterior one small rounded or weakly elongate, densely serrate plate, posterior one elongate or irregularly shaped plate with two distinct horn-shaped processes, in some species both signa are small plates without projections, one species with single signum with four horn-shaped processes.

Biology. The larvae of I. turkmenica and I. limoniella sp. nov. were observed feeding on Limonium sp. (FALKOvlTSH & BlDZlLYA 2006, 2009). Host plants for other species are unknown.

Distribution. Species of Ivanauskiella occur mainly in open landscapes (grasslands, coastal habitats, mountain steppe slopes) in the Palaearctic Region from Spain and Morocco to Mongolia and Southern Yakutia of Russia.

Remarks. Ivanauskiella bovis sp. nov., I. psamathias , I. nigripunctata sp. nov., I. albimarginata sp. nov., I. annekristinae sp. nov., I. ainella and I. turkmenica can be recognised by their forewing pattern. Superficial identification of the uniformly coloured species ( I. limoniella sp. nov., I. occitanica and I. sutteri sp. nov.) should be confirmed by examination of genitalia. The male genitalia of Ivanauskiella are rather uniform in the shape of gnathos, valva, sacculus and saccus. The shape and number of cornuti in the phallus as well as the shape of signa in the female genitalia are the most important diagnostic characters for separating species of Ivanauskiella .

Molecular data are available for I. limoniella sp. nov., I. occitanica and I. nigripunctata sp. nov. (HUFMFR et al. 2020: suppl. data 2), and partially for I. albimarginata sp. nov. and support the taxonomy based on morphological characters.

Key to adults based on external characters

1 Forewing light brown with costal and dorsal margin lighter. ................................ I. albimarginata sp. nov.

– Forewing with markings or uniformly coloured. ..... 2

2 Forewing with markings. .......................................... 3

– Forewing uniformly coloured. .................................. 5

3 Forewing with diffuse pale subapical fascia. ............... ................ I. turkmenica Ivinskis & Piskunov, 1980

– Forewing without pale subapical fascia. .................. 4

4 Forewing light brown with darker brown streak in fold and brown spots in cell and under costal margin, wingspan 10–13 mm. ...... I. ainella ( Chrétien, 1908)

– Forewing without brown streak in fold, wingspan 6.0–9.0 mm. .............................................................. 5

5 Wingspan 6.0– 7.1 mm, apex concolorous with forewing. ......................................................................... 6

– Wingspan 8.7–10.0 mm, apex of forewing spotted with white. ................ I. psamathias ( Meyrick, 1891)

6 Segment 2 of labial palpus brown with white apex, forewing light grey with small black markings. ............. .......................................... I. nigripunctata sp. nov.

– Segment 2 of labial palpus uniformly white, forewing white with large black markings. ................................. .......................................... I. annekristinae sp. nov.

7 Forewing ochreous brown, wingspan 10.0– 12.5 mm. ........................................................ I. bovis sp. nov.

– Forewing light brown to grey or greyish brown, with or without sheen, wingspan 7.5–9.0 mm. ................. 8

8 Forewing with distinct sheen. ... I. limoniella sp. nov.

– Forewing without sheen. .......................................... 9

9 Forewing white mottled with light brown. .................. ...................................................... I. sutteri sp. nov.

– Forewing greyish brown, without sheen. .................... ................................................ I. occitanica sp. nov.