Labidostomis (Labidostomis) balcanica Tomov, 1987

Regalin, Renato, 2017, A review of Labidostomis species similar to L. longimana from southeastern Europe with descriptions of two new species from Greece and Turkey (Coleoptera: Chrysomelidae: Cryptocephalinae: Clytrini), Zootaxa 4317 (2), pp. 321-337 : 323-324

Labidostomis (Labidostomis) balcanica Tomov, 1987

( Figs 5 , 11 , 16 , 22 , 28 , 34 )

Labidostomis balcanica Tomov, 1987: 25 (original description).

Type locality. “ Dalmatia , Biokovo ” [= Biokovo mountain range, Croatia].

Types examined. Holotype ( Fig. 34 ): ♂, “Biokovo / Dalmatia [w, h] // Holotypus [r, p] // Labidostomis / balcanica sp. n. / V. Tomov det. 1987 [w, p] // Mus. Nat. Pragae [p] / 66 150 [h] / Inv. [r, p]” (NMPC). Paratypes: 1 ♂ 3 ♀♀, same labels except “Paratypus [r, p]” and inventory numbers 66 151-66 154 (NMPC).

Additional specimens examined. 6 specimens — CROATIA: Insel Arbe [= Rab Isl.], 10.–21 . vii.1913, 1 ♂, without name of collector (NMPC); Makarska, S Biokovo, Vošac, 1000–1200 m, 22. vi.2000, 3 ♂♂ 2 ♀♀, R. Regalin leg. (RRCA).

Additions to description. Body length: ♂♂ 5.8–7.5 mm (holotype 7.5 mm); ♀♀ 5.8–6.3 mm.

Colouration. Labrum dark with anterior and lateral margins pale. Elytra of males completely pale brown, of females with very small blurred dark spot on humerus.

Mandibles and head ( Fig. 22 ). Head large with large deep frontal impression. Mandibles large but relatively narrow, distinctly constricted in preapical part, with dorsal keel sharp and elevated in basal half. Inner slopes oblique, angle between lateral and apical parts of inner margins is relatively sharp, about 90°, thus apical part of inner margin is nearly transverse.

Antennae ( Fig. 28 ). Antennomere IV subtriangular, ca. 1.45 times as long as wide.

Aedeagus ( Fig. 5 ). Apical quarter convergent with slightly concave margins, apex triangular with narrowly rounded tip. Dorsal median impression semi-elliptical, distinct, concave, with well-developed median keel. Apex of aedeagus with two inward triangular crooked folds, with narrow elongate cavity for insertion of anterior sclerite between folds. Operculum trapezoidal. Visible part of non-everted anterior sclerite transverse and thin, with thin, long and sharp median process. Ventral side of aedeagus moderately convex in lateral view and with two subapical shallow oblique impressions.

Everted aedeagus ( Fig. 16 ). Ejaculatory guide subpentagonal, compact in dorsal view, with thin short median process directed upwards, in lateral view with two arms coiled backwards. Lateral sclerites small. Anterior sclerite large, forming two concave wings connected in basal suture, in dorsal view with large v-shaped incision, in lateral view subtriangular.

Spermatheca ( Fig. 11 ). Vasculum C-shaped, relatively narrow, basal part distinctly longer than apical part, apex bent. Bulbus ca. as wide as long, with spherical glandular insertion. Ductus spermathecae very short, ca 1.1 times as long as vasculum, straight, without any coils or loops, proximal quarter slightly wider than rest of ductus. Bursa copulatrix with small sclerotized plate near entrance of ductus spermathecae.

Distribution. Croatia ( Tomov 1987, Regalin 2002). In the Palaearctic catalogue ( Regalin & Medvedev 2010) also Greece is listed in the distribution. This mistake probably resulted from the presumed synonymy with L. balcanica and L. graeca , respectively, mentioned in Warchałowski (2010).

Biology. The specimens from Vošac peak were collected on flowers of Dorycnium pentaphyllum ssp. pentaphyllum Scop. (Fabaceae) (Regalin 2000, pers. observ.).

Differential diagnosis. Labidostomis balcanica differs from similar species by the completely pale brown elytra in males (always with small dark spot on humeral calli in other species treated here). The most similar species seems to be L. leonardii sp. nov. from Kos Island and Turkey, as both species have mandibles with a sharp dorsal keel distinctly elevated in the basal half, aedeagus with a pair of shallow subapical impressions ventrally, and similar structure of spermatheca with ductus spermathecae short and straight, only slightly longer than the vasculum. Labidostomis balcanica differs from L. leonardii sp. nov. in colour, as the former has completely pale brown elytra in males (with small dark spots on humeral calli in L. leonardii sp. nov.), mandibles distinctly constricted subapically with sharp inner angle (not constricted subapically, inner margin regularly rounded in L. leonardii sp. nov.), antennomere IV subtriangular (almost parallel in L. leonardii sp. nov.) and spermatheca without visible bulbus (with bulbus in L. leonardii sp. nov.).

Comments. See the comments under L. longimana .

Figures

FIGURES 5 – 8. Aedeagus in dorsal, lateral and ventral views. 5 — Labidostomis balcanica; 6 — L. graeca; 7 — L. longimana; 8 — L. tymphristica. Scale bar: 0.5 mm.

FIGURES 11 – 15. Spermatheca. 11 — Labidostomis balcanica; 12 — L. longimana; 13 — L. tymphristica; 14 — L. daccordii sp. nov.; 15 — L. leonardii sp. nov. Scale bar: 0.25 mm.

FIGURES 16 – 18. Aedeagus with everted internal sac. 16 — Labidostomis balcanica; 17 — L. graeca; 18 — L. longimana. Not to scale.

FIGURES 22 – 27. Head and mandibles in frontal view. 22 — Labidostomis balcanica; 23 — L. graeca; 24 — L. longimana; 25 — L. tymphristica; 26 — L. daccordii sp. nov.; 27 — L. leonardii sp. nov. Not to scale.

FIGURES 28 – 33. Right male antenna. 28 — Labidostomis balcanica; 29 — L. graeca; 30 — L. longimana; 31 — L. tymphristica; 32 — L. daccordii sp. nov.; 33 — L. leonardii sp. nov. Not to scale.

FIGURES 34 – 39. Male habitus. 34 — Labidostomis balcanica (holotype, 7.6 mm); 35 — L. graeca (holotype, 6.7 mm); 36 — L. longimana (Bulgaria, 5.8 mm); 37 — L. tymphristica (holotype, 5.9 mm); 38 — L. daccordii sp. nov. (paratype, 6.5 mm); 39 — L. leonardii sp. nov. (holotype, 6.3 mm).