Epactus hirticornis, Colonnelli, 2014

Colonnelli, Enzo, 2014, Apionidae, Nanophyidae, Brachyceridae and Curculionidae except Scolytinae (Coleoptera) from Socotra Island, Acta Entomologica Musei Nationalis Pragae 54, pp. 295-422 : 345-346

Epactus hirticornis sp. nov.

( Figs 51–52 )

Type material. HOLOTYPE: J ( NMPC), ‘ Yemen, Socotra island // Al Haghier Mts. // Skant Mt. env. 1450 m // 12°34.6′N E 54°01.5′E / J. Bezděk leg. 12-13.xi.2010 ’. PARATYPES: 4JJ 3♀♀, same label data as holotype (4 NMPC, 3 ECRI) ; 2 JJ 2 ♀♀, ‘ Yemen, Socotra island // Hagher Mts. , Skant, / /N 12°34.557′ E 54°01.514′ // V. Hula & J. Niedobová leg. // 7-8.vi.2010 ’ ( NMPC) ; 6 JJ 3 ♀♀, ‘ Yemen, Socotra island // Al Haghier Mts. // Skant Mt. env. 1450 m // 12°34.6′N E 54°01.5′E // Jiří Hájek leg. 12-13.xi.2010 ’ (6 NMPC, 3 ECRI) ; 1 J, ‘ Socotra Is. ( YE) // Al Haghier Mts.Skant Mt. env. // 12°34.6′N, 54°01.5′E 1450 m // Jan Batelka leg. 12-13.xi.2010 ’ ( JBPC) ; 20JJ 9♀♀, ‘ Yemen, Socotra // Al Haghier Mts. [sifting] // Scant Mt. env. 1450 m // 12°34.6′N, 54°01.5′E // 12-13.xi.2010, P. Hlaváč’ (17 NMPC, 2 BMNH, 10 ECRI) ; 1 J, ‘ Yemen, Socotra island / Al Haghier Mts. // wadi Madar, 1180-1230 m // 12°33.2′N E 54°00.4′E // Jiří Hájek leg. 12-14.xi.2010 ’ ( NMPC) ; 1 ♀, ‘ Socotra Is. ( YE) // Dixam plateau // Firmihin ( Dracaena forest) // 12°28.6′N, 54°01.1′E 490 m // Jan Batelka leg. 15-16.xi.2010 ’ ( JBPC) ; 3 JJ 3 ♀♀, ‘ Yemen, Socotra Island // Hagher Mts. , Scand Mt. env.// montane evergreen woodland // 16-18.vi.2012 // 12°34.6′N E 54°01.5′E, 1450 m’, ‘Socotra expedition 2012 // J. Bezděk, J. Hájek, V. Hula, // P. Kment, I. Malenovský, // J. Niedobová & L. Purchart leg.’ (4 NMPC, 2 ECRI) .

Description. Male holotype. Body length 3.5 mm. Piceous, funiculus, tarsi, extreme base and distal half of tibiae pale ferruginous, scape somewhat darker, basal half of tibiae and club brown, apical comb of setae of tibiae golden-yellowish. Vestiture of very dense recumbent partly embricate roundish brownish and coppery to greenish metallic scales. Erect claviform elongate scales are on sides of epifrons, above eyes, on pronotum and are arranged in row on each elytral interval. Ventral surface with not very dense recumbent metallic roundish scales ( Fig. 51 ).

Head. Rostrum 1.20 times wider than long, sides faintly converging from base to slightly protruding pterygia. Epifrons at narrowest point half as wide as maximum width of rostrum, slightly depressed, rather coarsely punctured and scaled at base, its surface between antennae irregularly undulate and bare except for few erect setae, sides gently declining towards sides. Epistome U-shaped and separated from epifrons by thin carina. Scrobes short. Head on sides separated from rostrum by barely visible shallow impression, distance between eyes much greater than that between antennae, space between eyes slightly depressed and with shallow pit, vertex quite flat, temples shorter than greater diameter of eye, sides converging forward. Eyes quite small, subconical with their maximum convexity posteriorly from middle. Antennae thin; scape moderately curved, not very abruptly clubbed and with erect long claviform elongate scales on its anterior margin; funicular antennomeres I and II elongate and about of same length, antennomere I hardly wider than II, antennomeres III to VII only slightly diminishing in length, all longer than wide; club fusiform oval, about as long as three preceding antennomeres.

Prothorax 1.33 times wider than long, widest hardly basad of middle, depressed at basal third and then little convex in lateral view; anterior margin hardly narrower than basal one; sides subangularly rounded; punctures on disc completely hidden by thick vestiture, with barely visible trace of median keel. Scutellum indicated by small depression.

Elytra elongate oval, 1.40 times as long as wide, 1.47 times as wide as pronotum, depressed around scutellum, then flat on basal two thirds, apical declivity quite abrupt and almost perpendicular; striae formed by rather sparse rows of roundish to elongate punctures; intervals hardly convex and much wider than striae.

Legs quite short; femora clubbed, edentate; tibiae slightly curved on apical third, meso- and particularly metatibiae granulate on inner margin, apex with stout acute internal mucro; tarsi short, tarsomere I little longer than wide, tarsomere II and widely bilobed tarsomere III transverse, apical tarsomere almost three times as long as tarsomere III.

Ventral side. Metaventrite and abdominal ventrite I flat.

Variability. All specimens are similar to the holotype. Females, besides the abdomen slightly convex and smaller tibial mucros, have plumper elytra and their elytral striae II and III are more or less sinuous from the apical third because interval III is here a little wider that the adjoining ones and with a faint trace of tubercles. The colour of the metallic scales varies a little from golden to greenish-gold. Some specimens have also a thin longitudinal median keel on pronotum.

Male genitalia. Aedeagus as depicted in Fig. 52 .

Body length 2.8–4.4 mm.

Differential diagnosis. The present species agrees with Epactus Marshall, 1955 in all its salient characteristics, namely bisetose mentum, small size, quite short rostrum, subperpendicular epistome, comparatively short second ventrite ( MARSHALL 1955). However, all Socotran species of Epactus are immediately identified from the Kenyan E. coenosus Marshall, 1955 already by their not pedunculate mentum, setose scape, scrobes not extending backwards up to the subconically protruding eyes, interocular distance at least slightly wider than the base of rostrum, somewhat carinate pronotum, elytra with the basal angles not much extending beyond the base of pronotum and protibiae not denticulate but set with more or less stiff setae. On the other hand the second hitherto known species of this genus, E. impar Voss, 1965 from Tanzania, is at once distinguished from the Socotran Epactus by its eyes not strongly convex, lack of erect setae on elytra, and posterior tibiae widened at both inner and outer apical margin ( VOSS 1965). Perhaps future findings of additional continental African species of this genus may prove that the above mentioned characters are worthy of a generic name for the Socotran taxa, but for the time being it seems wise not to propose a new name, considering the present poor knowledge of the African peritelines. See below for separation of E. hirticornis sp. nov. from the close E. hispidus sp. nov.

Etymology. The species name, Latin adjective hirticornis (- is, - e), meaning ‘with hirsute antennae’, emphasizes an obvious feature of the new species.

Collection circumstances. Sifted from leaf litter in montane evergreen woodland in the highest parts of the Hagher mountains (J. Hájek, pers. comm.).

Distribution. Endemic to Socotra Island.

Figures

Figs 47–52.47–49 – Parvorhynchus sordidus sp.nov., holotype:47 – habitus; 48 – habitus in side view;49 – aedeagus in dorsal view. 50 – Otiorhynchus (Namertanus) argus Reitter, 1896 from Abkhazia, habitus. 51–52 – Epactus hirticornis sp. nov.: 51 – habitus of the holotype; 52 – aedeagus of a paratype in dorsal view.