Rhinusa mateui ( Hoffmann, 1965 )

Caldara, Roberto & Toševski, Ivo, 2019, Rhinusa Stephens: a taxonomic revision of the species belonging to the R. linariae R. herbarum, R. melas, and R. mauritii groups (Coleoptera Curculionidae), Zootaxa 4679 (2), pp. 318-340 : 328-329

Rhinusa mateui ( Hoffmann, 1965)

Figs 6 , 14, 15 , 29 , 35, 41

Gymnetron mateui Hoffmann, 1965: 26 .

Rhinusa mateui (Hoffmann) . Caldara 2001: 185. Caldara et al. 2010: 52. Alonso-Zarazaga et al. 2017: 204.

Type locality. Chabt el Karka N’Igli ( Algeria) .

Type series. This species was described from a numerous series of specimens collected in north-western Algerian Sahara. In coll. Hoffmann ( MNHN) we studied the holotype (a male) and four paratypes (two males and two females).

Redescription. Male. Body: oval, slender ( Fig. 6 ). Rostrum: black with reddish apex, short (Rl/Pl 0.75), cylindrical; in lateral view weakly curved, of about same width from base to apex ( Fig. 14 ); in dorsal view with subparallel sides, with weakly visible scrobes, sparsely striate-punctate in basal half, further almost smooth and shining, in basal half with rather dense recumbent to subrecumbent long (l/w 6–9) setiform whitish scales. Head: between eyes slightly wider than rostrum at base, with narrow fovea. Eyes almost flat. Antennae reddish with brown club, inserted at middle of rostrum; scape 4.0× longer than wide, funicle slightly longer than scape, with segment 1 twice longer than wide, distinctly stouter and 1.5× longer than segment 2, which is 1.5× longer than wide, segment 3 about as long as wide, segments 4 and 5 transverse; club oval, with segment 1 less pubescent than others. Pronotum: black, with moderately dense and shallow punctures a little irregularly arranged, and with rather broad, slightly rugulose and slightly shining intervals, well visible between rather dense recumbent to subrecumbent long to very long (l/w 8–12) setiform whitish scales; transverse (Pw/Pl 1.42), with strongly rounded sides, weakly constricted at apex, widest in basal half, weakly convex. Elytra: black, 1.30× as long as wide, subrectangular, slightly wider than pronotum (Ew/Pw 1.18), weakly convex on disc; interstriae well visible between sparse recumbent to suberect long setiform whitish scales, 0.75–1.00× as long as width of interstria (l/w 7–10) and arranged in a regular row; striae well visible, one third as wide as interstriae, with a row of scales shorter and narrower than those on interstriae. Legs: slender, with sparse recumbent to subrecumbent greyish scales distinctly shorter than width of tibia; femora brown, subclavate, without tooth; tibiae reddish brown, long, with outer margin curved inward apically; unci black, stout, all of same size; tarsi reddish brown, with tarsomere 1 1.5× longer than wide, tarsomere 2 slightly longer than wide, tarsomere 3 weakly bilobed and moderately wider than tarsomere 2, onychium about as long as tarsomeres 1–3 taken together; claws dark brown, equal in length. Venter: metasternum black, with sparse recumbent to suberect long setiform whitish scales. Mesepimera, mes- and metepisterna with dense long setiform whitish scales. Abdomen black, with dense irregular punctures, rather visible between sparse recumbent to suberect setiform greyish scales; length ventrites 1+2/3+4 1.93. Penis: body of penis moderately long (l/ w 2.9), with slightly concave sides, with subacutely rounded apex, in lateral view with sides higher apically; apodemes shorter than body and in lateral view on same ideal plane joining base and apex of median lobe ( Fig. 29 ).

Female. Rostrum longer (Rl/Pl 0.92) ( Fig. 15 ), smooth and shining, uncus of metatibiae very small. Spiculum ventrale: arms distinctly spaced each other, apodeme shorter than arms ( Fig. 35 ). Spermatheca: ramus and collum well-developed ( Fig. 41 ).

Variability. Length 1.3–1.6 mm. The pronotum is slightly variable in width, with more or less rounded sides.

Remarks and comparative notes. Apart from the male genitalia this species also differs from R. herbarum by the smaller size, the scales of elytral interstriae arranged in a single regular row, the rostrum of the female distinctly longer, the tarsomere 3 slightly bilobed and only moderately broader that tarsomere 2. It shares this last character with R. korotyaevi .

Biological notes. According to their collector, J. Mateu, the specimens of the type series came out from dry branches of Launaea arborescens (Batt.) Murb. (erroneously reported by Hoffmann as Launia). This datum must be confirmed since the genus Launaea belongs to the Asteraceae , a family unknown to serve as a host for species of Rhinusa . On the contrary, some specimens were collected on Kickxia aegyptiaca fruticosa (Desf.) Wickens in Tunisia (det. Péricart). This is probably a true host plant, since, as above reported, the closely related species R. herbarum also feeds on plant species from the genus Kickxia .

Distribution. Algeria, Tunisia.

Non-type material examined. Algeria: Biskra, 24.–25.V.1971, leg. Hoffer & Horák (1, RCCM); Hammam Salihine, 29.–30.V.1971, leg. Hoffer & J. Horák (1, RCCM). Tunisia: Carthage, VI.2003, leg. Ernest (1, MMCT); 40 km N of Gabes, 21.V.2004, leg. Sechi (1, RCCR); 35 km N of Kasserine, 1030 m, 27.IV.1998, leg. Borovec (1, RBCS; 1, RCCM); Matmata, 450 m, 20.IV.1995, leg. Košťál (11, MKCH); Sfax, 1896, leg. de Valouger (1, MNHN); 15 km W of Zarzis, road to Médénine, salty soil, 28.III.1979, on Kickxia aegyptiaca (L.) Nab. ssp. fruticosa (Desf.) Wick. , leg. Péricart (3, JPCM).

Figures

FIGURES 1‒9. Habitus of (1) Rhinusa linariae, male; (2) R. brisouti, male; (3) R. kumatschevi, male; (4) R. herbarum, male; (5) R. vulpeculus, holotype male; (6) R. mateui, female; (7) R. melas, male; (8) R. korotyaevi, paratype male; (9) R. mauritii, male. Not to the same scale

FIGURES 10‒22. Rostrum of (10) Rhinusa linariae, male; (11) R. linariae, female; (12) R. herbarum, male; (13) R. herbarum, female; (14) R. mateui, male; (15) R. mateui, female; (16) R. melas, male; (17) R. melas, female; (18) R. korotyaevi, male; (19) R. korotyaevi, female; (20) R. mauritii, male; (21) R. mauritii, female; (22) R. antirrhini, male.

FIGURES 23‒32. Profemur and protibia of (23) Rhinusa bipustulata, male; (24) R. linariae, male; (25) R. tetra, male; (26) R. tetra, female. Penis in dorsal view of (27) R. linariae; (28) R. herbarum; (29) R. mateui; (30) R. melas; (31) R. korotyaevi; (32) R. mauritii.

FIGURES 33‒44. Spiculum ventrale of (33) Rhinusa linariae; (34) R. herbarum; (35) R. mateui; (36) R. melas; (37) R. korotyaevi; (38) R. mauritii. Spermatheca of (39) R. linariae; (40) R. herbarum; (41) R. mateui; (42) R. melas; (43) R. korotyaevi; (44) R. mauritii.