Neohydnobius irregularis, Newton & Švec & Fikáček, 2017

Newton, Alfred F., Švec, Zdeněk & Fikáček, Martin, 2017, A new genus and two new species of Leiodinae from Chile, with keys to world genera of Sogdini and Leiodinae from Chile and Argentina (Coleoptera: Leiodidae), Acta Entomologica Musei Nationalis Pragae 57 (1), pp. 121-140 : 133-134

Neohydnobius irregularis sp. nov.

( Figs 5A–D )

Type locality. Chile, La Araucanía Region, Malleco Province, Sendero Piedra de Aguila at Araucaria Milenaria , 37°49.5′S, 73°0.8′W, 1180 m a.s.l.

Type material. HOLOTYPE: ♂ ( NMPC): “ CHILE: IX. La Araucanía Region / PN Nahuelbuta, Sendero Piedra / de Aguila at Araucaria Milenaria / 27.xi.-12.xii.2013; 1180 m / 37°49.5’S 73°0.8’W; Fikáček, / Kment & Vondráček, CH15 // flight intercept trap in sparse / Nothofagus / Araucaria forest with / understory of bushes+ Chusquea / and numeous [sic!] mosses” . PARATYPES: CHILE: 2 ♂♂, 1 ♀ ( NMPC, ZSPC): same data as the holotype ; 2 ♂♂ 7 ♀♀ [1♂ 1♀ dissected on permanent microscope slide in Permount] ( FMNH): CHILE: Cautín, Bellavista, N shore Lago Villarrica, 310 m, [39°12′S 72°8′W], 15-30.xii.1982, A. Newton & M. Thayer ANMT 655, Valdivian rainforest, window trap; 2♀♀ ( FMNH): same data except FMHD#82-778, carrion trap (squid); 2 ♂♂, 1 ♀ 5 spec. ( FMNH): CHILE: Malleco, Malalcahuello (12 km E), 1350 m, [38°26′S 71°30′W], 13-31.xii.1982, A. Newton & M. Thayer ANMT 650, FMHD#82-823, Nothofagus dombeyi-Araucaria forest, window trap ; 1 ♂ 2 ♀♀ ( FMNH): CHILE: Malleco, Malalcahuello (14 km E), 1570 m, [38°26′S 71°29′W], 13-31.xii.1982, A. Newton & M. Thayer ANMT 649, FMHD#82-820, Nothofagus pumilio-Araucaria forest, window trap; 1 ♂ ( FMNH): CHILE: Malleco, Malalcahuello (6.5 km E), 1080 m, [38°28′S 71°31′W], 13-31.xii.1982, A. Newton & M. Thayer ANMT 651, FMHD#82-846, Nothofagus dombeyi w/ Chusquea , window trap; 1 ♀ ( FMNH): CHILE: Malleco, P.N. Tolhuaca, Lago Malleco, 890 m, [38°12′S 71°52′W], 1.i.1983, A. Newton & M. Thayer ANMT 651.3, FMHD#83-887, Nothofagus forest (disturbed), berl., wet leaves & flood debris, forest stream; 2 ♂♂ 2 ♀♀, 13 spec., [1♂ 1♀ dissected on permanent microscope slide in Permount] ( FMNH): CHILE: Ñuble, Recinto (19.5 km ESE), Las Trancas, 1250 m, [36°54′S 71°28′W], 10.xii.1982 - 3.i.1983,A. Newton & M. Thayer ANMT 647, FMHD#82-818, Nothofagus forest, window trap; 1 ♀ ( FMNH): same data except FMHD#82-817, screen-sweeping vegetation; 3 ♂♂ [1♂ dissected on permanent microscope slide in Permount] ( FMNH): CHILE: Ñuble, Recinto (22.7 km ESE), 1330 m, [36°55′S 71°27′W], 10.xii.1982 - 3.i.1983, A. Newton & M. Thayer ANMT 646, FMHD#82-815, Nothofagus forest, window trap.

Description. Body length 1.5–2.1 mm, 2.1 mm in holotype. Length of body parts (holotype): head 0.3 mm, pronotum 0.6 mm, elytra 1.2 mm, antenna 0.6 mm, aedeagus 0.5 mm, spermatheca 0.1 mm. Maximum width of body parts (holotype): head 0.6 mm, pronotum 1.0 mm, elytra 1.1 mm.

Body oval ( Fig. 5A ), moderately convex ( Fig. 5B ), head, pronotum, elytral lateral parts and apex and legs red-brown, elytra brown-black, AI–AVI reddish, rest of antenna infuscate. Venter chestnut coloured, central part of mesoventrite darker. Head, pronotum and scutellum transversely microsculptured by elongate cells, elytra transversely strigose. Dorsal surface punctured.

Head. Microsculpture fine, distinct, finer and denser on clypeus. Dorsal surface with scattered fine punctures separated by about 2–3 times or more their diameter. Two large punctures on front, two large punctures on one side of clypeus, three large punctures at other side of clypeus. Relative length of AIII: AII = 1.3. Ratio of width of AX: AXI = 1.2.

Pronotum. Microsculpture distinct. Punctation fine, similar to that on head, irregular, punctures separated by about 1–10 or more times their own diameter. Before base, at basal third and behind anterior margin of pronotum with some scattered larger punctures. Widest at base. Base not bordered, slightly curved, feebly angled towards blunt moderately rounded hind pronotal angles. Hind angles blunt and broadly rounded in lateral view. Lateral sides conically narrowed anteriorly in dorsal view; slightly curved in lateral view. Anterior margin not bordered.

Scutellum. Small with rounded apex, covered by several transverse lines.

Elytra. Transversely strigose, strigae oriented obliquely medio-caudally, separated approximately by about 0.03 mm connecting elytral punctures. Irregularly punctured, punctures separated by about 2–4 times their own diameter tending to be seriate in some places. Without distinct regular longitudinal rows of punctures. Along lateral margins and near elytral apex several short yellow erect setae. Sutural stria confined to posterior three quarters of elytral length.

Legs. Tarsal formula 5-4-4. Male with anterior TI distinctly, TII–TIII feebly widened, TI– TIV each bearing one (TII–TIV) or multiple (TI) pairs of very large tenent setae; remaining tarsi of male and all tarsi of female slender and without tenent setae. Longest terminal tibial spine shorter than TI. Lateral and apical spines of mid- and hind tibiae shorter than relevant TI. Hind tibiae bent in blunt angle in middle, then gradually widened apically.

Mesoventrite. Hollowed between procoxal rest and longitudinal posterior carina. Procoxal rest margined anteriorly with longitudinal narrow keel in middle. Longitudinal posterior carina steeply falling between mid-coxae, feebly rounded in lateral view.

Metaventrite. Coarsely and densely punctured centrally, punctures separated by about 0.5–1.0 times their own diameter, punctation sparser anteriorly, laterally without punctures, microsculptured.

Metathoracic wings fully developed.

Abdominal ventrites. Very finely punctured and setose. Without unusual characters.

Genitalia. Aedeagus as in Fig. 5C ; parameres with one apical seta medially. Ovipositor normal, with paired slender proximal and distal gonocoxites and styli. Spermatheca as in Fig. 5D .

Variability. Species varies in colour – one of the paratypes with dark chestnut coloured elytra only slightly darker than head and pronotum; antennae unicolorous red-brown in another paratype.

Differential diagnosis. Neohydnobius irregularis sp. nov. differs from both previously known species by irregularly punctured elytra; further it differs from N. brevis Jeannel, 1962 by the angularly truncated apex of the median lobe that is broadly rounded in the compared species. The new species differs also from N. argentinicus ( Hlisnikovský, 1964) by possessing a coarsely punctured metaventrite while the metaventrite is punctured as fine as abdomen in N. argentinicus .

Etymology. The species name is a Latin adjective meaning irregular, in reference to the irregularly punctures elytra characteristic for the species.

Distribution and biology. This species has a relatively small known range in Ñuble, Malleco and Cautín provinces, in regions VIII (Biobío) and IX (Araucanía), in both the Andes and coastal Nahuelbuta mountains ( Fig. 7B ). Specimens have been collected in various kinds of indigenous forests (Valdivian rainforest and Nothofagus -dominant forests, with or without Araucaria trees or Chusquea bamboo understory), at elevations from 300 m to nearly 1600 m, mainly by use of flight intercept (window) traps. No associations with fungi are known.

Figures

Fig. 5. Habitus and genitalia of Chilean Leiodinae. A–D – Neohydnobius irregularis sp. nov. (A–C – holotype; D – female paratype). E–G –Metahydnobius forticornis (Champion, 1918), male specimen from PN Nahuelbuta. A, E – body in dorsal view; B, F – body in lateral view; C, G –aedeagus in dorsal view; D – spermatheca.

Fig. 7. Type locality and distribution of Anaballetus chilensis sp. nov. and Neohydnobius irregularis sp. nov. A–B – distribution of both species in Chile; C – flight intercept trap in the Araucaria araucana forest in PN Nahuelbuta (37°49.5′S 73°0.8′W) at which examined specimens were collected; D – general view of the Araucaria forests in the area where specimens were collected (PN Nahuelbuta, view from Piedra de Aguila towards Pehuenco). Photos by M. Fikáček.