Meligethes foddaii Audisio, De Biase & Trizzino, 2009

Audisio, Paolo, Biase, Alessio De, Trizzino, Marco, Mancini, Emiliano & Antonini, Gloria, 2009, A new species of Meligethes (Coleoptera: Nitidulidae: Meligethinae) of the M. lugubris complex from Sardinia *, Zootaxa 2318, pp. 386-393 : 387-390

Meligethes foddaii Audisio, De Biase & Trizzino , sp. nov.

( Figs 1, 3, 7–8)

Diagnosis. Small-sized (length 1.78–2.02 mm), body shiny black, legs and antennae blackish to chestnut brown. Maximum pronotal width near posterior angles ( Fig. 1). Similar to the widespread European species M. lugubris recently re-described by Audisio (1993), but with interspaces between dorsal punctures on pronotum and most of elytra smooth and shining. Median lobe of aedeagus distinct, slightly more parallelsided distad ( Fig. 8), and tegmen darker, distinctly more pigmented than median lobe. Differentiated from the closely related M. gagathinus by smaller, more elongate, and more parallel-sided body (length 2.1–2.6 mm in M. gagathinus , 1.8–2.0 in M. foddaii sp. nov.), elytral sides less arcuate ( Figs 1–2), more extruded paramere apices ( Figs 7, 9), and more narrow prosternal process ( Figs 3–4).

Type material. Holotype ♂: Italy, Sardinia, Medio Campidano province, Domusnovas, Lago Siuru, 390 m, 39.22.12 N, 8.36.59 E, 19.V.2008, P. Audisio, M. Trizzino, G. Nardi & M. Bardiani leg., on apical (nonflowered) stems of Mentha insularis Requien (= Mentha suaveolens Ehrh. subsp. insularis (Req.) Greuter ; Lamiaceae ) ( CAR).

Paratypes: same data as holotype, 4 ♂, 5 ♀♀ (CAR, NMP); Italy, Sardinia, Medio Campidano province, Villacidro, near Montimannu dam, 256 m, 39.24.02 N, 8.41.56 E, 6.IX.2006, G. Nardi leg., grassnetting on flowers of Mentha insularis , 2 ♀♀, 1 ♂ (CAR, CNBFVR) .

Other material examined. Italy, Sardinia , Nuoro province, Oliena, near San Giovanni , 150 m, 6.VI.1995, F. Angelini leg., 1 ex ( CAR) ; Italy, Sardinia , Nuoro province, Gennargentu Massif, Montarbu Forest , Mount Tonneri , 1300 m, 2.V.1983, P. Audisio leg., 2 ex ( CAR) ; ibidem, 989 m, 16.V.2008, P. Audisio & M. Trizzino leg., 1 ex ( CAR) ; Italy, Sardinia , Cagliari province, Geremeas, Geremeas river , 150 m, 18.VI.1976, C. Meloni leg., 2 ex ( CAR) ; Italy, Sardinia , Cagliari province, Elmas near Cagliari , 10 m, 1.X.1973, P. Leo leg., 1 ex ( CAR) ; France, Corsica , Casta , 270 m, 22.VII.1976, A. Sette leg., 5 ex ( CAR) .

Description. Male [measurements refer to holotype]. Length 1.90 mm; width (at elytral widest point) 1.00 mm. Body elongate, narrow, transversely convex and moderately parallel-sided ( Fig. 1), black and shining, with short and fine silvery to golden-olivaceous pubescence. Legs and antennae blackish.

Head with dorsal punctures as large as or slightly smaller than an eye facet, moderately impressed, separated by nearly one diameter, surface smooth and shining; front margin of clypeus straight, completely bordered, with almost right angles. Fronto-genal grooves narrow and shallow, but distinct. Antennae small, of normal size for group (cf. Fig. 1), with third segment slender, longer than second; antennal club small.

Pronotum only moderately narrowed anteriorly, 1.65 times as wide as long, broadest close to posterior angles (cf. Fig. 1); sides narrowly bordered; posterior angles slightly obtuse but distinct. Posterior base faintly sinuate on either side of scutellum; pronotal punctures and surface smooth and shining, each puncture nearly as large as an eye facet and separated by one diameter or less.

Scutellum medium-sized, densely and uniformly punctate; surface exhibiting a faint trace of reticulate microsculpture. Elytra (cf. Fig. 1) nearly 1.17 times as long as wide, broadest in basal fifth, scarcely wider than pronotum (1.06) and nearly twice as long; feebly raised, humeral striae absent; elytral punctures in basal half as on head and pronotum, but slightly coarser and more elongate, exhibiting a feeble transverse rugosity and with a shiny surface between punctures. Elytral punctures becoming finer and shallower towards their hind end.

Ventral surface black, with sparse fine silvery pubescence. Prosternal antennal furrows strongly raised. Prosternal process rather long, moderately wide and parallel-sided (cf. Fig. 1), subtruncate at apex, as wide as posterior tibiae.

Metasternum moderately convex (punctures as on head and pronotum, surface shiny), with a barely distinct and posteriorly widened longitudinal impression on posterior two-thirds, and a well-raised elongate medial tubercle. Caudal marginal line of posterior coxal cavity closely following posterior edge, turning back just before outer end. Last visible abdominal sternite with a markedly raised obtuse projection, distally concave, as in males of M. lugubris and M. gagathinus .

Protibiae (cf. Fig. 1) with outer edges finely crenulate from basal third, with subapical group of 5–7 sharp teeth, the first and penultimate tooth markedly bigger than the rest; protarsi barely as wide as antennal club; metatibiae narrow, inner edges not sinuate (cf. Fig. 1); tarsal claws simple.

Genitalia. Tegmen as in Fig. 7, rather strongly sclerotized and dark, with a shallow, V-shaped median excision, and apex markedly projected distad and scarcely pubescent; median lobe of aedeagus elongate, narrow, nearly 2.4 times as long as wide (cf. Fig. 1), less sclerotized and paler than tegmen, widest in distal three-fifths, parallel-sided distad and proximad, apex subtruncate and minutely incised. Male genitalia exhibiting a rather unusual contrast between the rather strongly pigmented, blackish-brown tegmen, and the orange-yellowish and scarcely pigmented median lobe.

Female. Protarsi more narrow (~0.7 times as wide) than in male. Metasternum not impressed longitudinally. Ovipositor nearly indistinguishable from that of M. lugubris (fig. 160 l in Audisio 1993), yellowish, with apical suture of coxites slightly darker, apex acuminate, styli relatively short and inserted at a distance from apex equal to their length; outer subdivision of coxites moderately long and narrow; “central point” placed at distal three fifths, without ventral spicule; transverse suture nearly straight; external angles of basicoxites moderately sharp.

Variability. Length 1.78–2.04 mm. Dorsal punctures slightly variable in density, but usually conforming to the pattern described. Antennae, tibiae and tarsi frequently paler, at least partially nut-brown.

Comparative notes. Meligethes foddaii sp. nov. exhibits a dorsal habitus ( Fig. 1) similar to that of small specimens of M. lugubris (widespread in Europe and peninsular Italy), but with a much shinier dorsal surface. The new species is also recognizable by the proportionally larger male genitalia, the more strongly pigmented and darkened tegmen, and by the more parallel-sided shape of the distal portion of the median lobe of the aedeagus ( Figs 5–8). Easily distinguishable from the closely related M. gagathinus (widespread in Europe and peninsular Italy) by the smaller, narrower, and more parallel-sided body ( Figs 1–2), by the parameres more protruding laterad to the distal portion of tegmen ( Figs 7–10), by the narrower prosternal process ( Figs 3–4), and by the slightly narrower male protarsal plate ( Figs 1–2).

Geographic distribution. All known specimens are from the above-mentioned localities in Sardinia and Corsica. This species appears not to be particularly rare, and could be more widely distributed, in suitable habitats, throughout both islands.

Biological notes. The type and non-type specimens were all collected from apical stems of the common plant Mentha insularis Requien [= Mentha suaveolens Ehrh ssp. insularis (Req.) Greuter ] ( Lamiaceae ), a subendemic W-Mediterranean species known to occur in the Corso-Sardinian plate and Balearic Islands, in wet places near lakes and ponds, and on the edges of river banks, from sea level up to 1300m (Gennargentu Massif). The adults are active on host-plants from early May to late November, two-three months before flowering time, but reproduction appears to be extremely tardive for a Mediterranean Meligethes , occurring mainly between late July and early October.

Etymology. This species is named after our Sardinian friend and colleague Dr. Sebastiano Foddai (Department of Vegetal Biology, Sapienza University of Rome), whose main scientific research is devoted to the biochemistry of secondary substances extracted from Sardinian endemic plant species.