Image key to the wingless Cryptorhynchinae of the Caucasus Note. A reliable and quick identification can be made via the aedeagus of the males (see also Fig. 1). Only then should the females be assigned on the basis of the elytra scales and bristles from the same locality. Sifting of wingless Cyptorhynchinae, the main method by which they are collected, always contains a large number of specimens, almost always including males. 1 Base of each elytron strongly S -shaped, protruding towards the pronotum with corners that extend far forward. Length: 3.0– 4.9 mm .................................................................... Acallocrates colonnellii Bahr, 2003 1* Base of the elytron straight or only slightly convex over the entire length protruding towards the pronotum.............. 2 2 Male with a distinct (strongly sclerotised) sclerite (= inner sac structure) in the endophallus.......................... 3 2* Males without a recognisable, strongly sclerotised (more or less complex) sclerite in the endophallus (instead sometimes with a blurred, ‘cloudy’ appearing endophallus consisting of many tiny hooks).......... Onyxacalles & Echinodera ........ 11 3 Males with a strongly sclerotised, elongate, parallel-sided or X-shaped sclerite in the endophallus, basally (sometimes also apically) with a closed or semicircularly open structure (see couplet 2)......................... Kyklioacalles ………. 4 3* Males with sclerite in the endophallus differently shaped (without a circular or only semicircularly opened structure)...... 6 --- Kyklioacalles --- 4 Elytra with patches of pale scales (‘eyespots’) absent, instead with light-coloured, irregularly delimited, cloudy markings on the elytra and a prominent X-shaped inner sac structure of the aedeagus; tiny species: 3.5 mm; with a long, bottle-necked tip of the aedeagus (couplet 4*, left). Length: 3.5–5.2 mm ........................................................................... Kyklioacalles ocellus Stüben & Astrin, 2025 5* Smaller species, 4 mm)............................................................................. Subgenus: Ruteria ………. 18 --- Echinodera s. str. subg.--- 15 Spine at the end of the hind tibia of males curved inwards at almost a right angle. Length: 2.2–3.0 mm........................................................................................ Echinodera davidiani Savitsky, 1999 15* Spine at the end of the hind tibia of males straight or weakly curved............................................ 16 16 Elytra longer, obovate, apex rounded narrowly oval; elytral bristles very short (at most 1.5× longer than wide)). Length: 2.6–3.4 mm ............................................................. Echinodera orientalis (A. & F. Solari, 1907) 16* Elytra wider, short ovally rounded with apex more broadly rounded; elytral bristles longer (2×–4× longer than wide)..... 17 17 Elytral bristles very long, 3.5×–4× longer than wide (couplet 16*, left); striae and the punctures between the outermost elytra intervals narrow; median lobe of aedeagus strongly curved towards the tip when viewed ventrally. Length: 2.2 mm ..................................................................... Echinodera borjomiensis Stüben & Astrin, 2025 17* Elytral bristles short, only 2×–2.5 x longer than wide (couplet 16*, right); elytral striae strongly punctate between the narrower outermost elytra intervals; median lobe of aedeagus nearly flat when viewed laterally. Length: 1.9–3.1 mm .................................................................................... Echinodera horridula (Reitter, 1888) --- Ruteria subg. --- 18 Sides of the pronotum with light brown and white scales; aedeagus with a narrow, elongate apex. Length: (2.7) 4.0– 5.6 mm. Note. According to Savitsky (1997), the central, southern and southeastern European species is also said to occur in Georgia (the species was described from Austria, Styria). Savitsky mentions only 2 females and 1 male (it remains unclear whether the aedeagus shown is from this male.). In order to take this unusual disjunct distribution into account, the species is also mentioned here for the Caucasus, despite considerable doubt (to facilitate subsequent identification)........................................................................................ Echinodera (Ruteria) hypocrita (Boheman, 1837) 18* Sides of the pronotum with dark brown or black scales; aedeagus not protruding like a bottle neck at tip. Note. So far, molecular data from this group are only available for E. teplovi. Therefore, I follow here the exclusively morphological differential diagnosis of Savitsky, 1997, as far as it seemed comprehensible to me after examination of the type material (see illustrations of the habitus of holotypes). I supplement with illustrations of the aedeagus; however, further studies are urgently needed here on the generally poorly researched species of the subgenus Ruteria from the Caucasus ............................................................................... Echinodera anatolica group ………. 19 19 Elytra with 7th stria at end of basal 1/4 abruptly ending; mesosternal part of receptaculum with distinct tubercle; aedeagus slender, tapered. Length: 4.0– 5.5 mm .............................. Echinodera (Ruteria) kakhetica (Savitsky, 1997) (probably a synonym of E. hyrcania, see comment Stüben, 2018: 367) 19* Elytra with 7th stria not abruptly ending at the end of basal ¼; mesosternal part of receptaculum usually without tubercle.... .................................................................................................. 20 20 Middle part of metathorax and ventrite 1 covered with dissected scales; uncus of fore tibia in male beveled triangular, split (see couplet 20); apical part of ventrite 1 strongly sloping, at nearly right angle to plane of ventrite 2; aedeagus broader, obtuseangled (dorsal view). Length: 4.1–4.9 mm ......................... Echinodera (Ruteria) meskhetica (Savitsky, 1997) 20* Middle part of metathorax and ventrite 1 covered with elongate undissected scales; uncus of fore tibia in male of different shape; apical part of ventrite 1 slightly or moderately sloping to plane of ventrite 2................................ 21 21 Body of male 1.78–1.85, of female 1.77–1.91, times as long as wide; anterior part of receptaculum covered with hairs and admixture of scales divided into several filiform lobes; uncus of fore tibia in male wide; aedeagus wider towards the tip. Length: 4.0– 5.5 mm .................................................. Echinodera (Ruteria) hyrcanica (Savitsky, 1997) 21* Body of male 1.58–1.77, of female 1.59–1.80, times as long as wide; anterior part of receptaculum covered with hairs and sparse narrow scales divided into 2 filiform lobes; uncus of fore tibia in male weakly dilated; aedeagus with clearly bent tip (lateral view). Length: 3.9–5.0 mm.................................. Echinodera (Ruteria) teplovi (Savitsky, 1997)

Published as part of Stüben, Peter E., 2025, New species and an image key to the wingless Cryptorhynchinae of the Caucasus (Coleoptera: Curculionidae: Tylodina) - a hypothesis on the spread of forest and open land species in the Western Palaearctic, pp. 235-259 in Zootaxa 5647 (3) on pages 244-252, DOI: 10.11646/zootaxa.5647.3.2, http://zenodo.org/record/15819671