Pseudochillus (Micropseudochillus) thailandicus 2015

Fouquè, René, 2015, A review of the genera Indostola, Tagenostola, Indochillus, Pseudethas, and Pseudochillus gen. nov. in South East Asia (Coleoptera: Tenebrionidae: Stenosini), Acta Entomologica Musei Nationalis Pragae 55 (1), pp. 217-242 : 236-237

Pseudochillus (Micropseudochillus) thailandicus sp. nov.

( Figs 11 , 25 , 35 , 42 )

Type locality. Thailand, Doi Suthep, Monthathan, 650 m a.s.l.

Type material. HOLOTYPE: ♂, ‘ THAILAND / Doi Suthep , 650 m / Monthathan, 14.XII.96- / 10.I.97, Schwendingerʼ ( MHNG).

Description. Body length 3.9 mm, body width 1.2 mm. Body and antennae dark brown, legs rusty brown.

Head length/width ratio 1.04, widest at anterior margin of eyes. Tempora widest at posterior margin of eyes, from there slowly narrowed at distance equal to 0.75 eye length, then rounded and sharply narrowed to cervix. Genae arched from posterior margin of eyes to the widest place, there arched and directly narrowed to clypeus, margins behind clypeus very finely serullate. Clypeus concave, with small tooth situated slightly to the right. Left half of clypeus slightly more concave than right one. Suborbital keel flat, indistinct. Eye groove stretches from posterior margin of eye to cervical constriction. The latter prominent, narrower than distance between inner margin of eyes and concave, vertex convex, occiput with mid-longitudinal impression which starts on top of vertex. Frons with two distinct impressions. Ratio of head/ cervix widths 1.86. Eyes ( Fig. 35 ) completely divided by genae, dorsal part with 15 facets in 3 rows, ventral part with 6 facets arranged in an elongated triangle. Punctation rounded, larger on vertex sideways of impression, towards clypeus almost disappearing. Punctures on vertex almost touching each other. Punctures on vertex and on genae with thick, yellow, forward-oriented setae as long as puncture diameter, clypeus also covered with prominent setae oriented towards middle of clypeus, setae of the same length as those on vertex. Space between punctures finely wrinkled, on frons glossy. Antennae ( Fig. 25 ) with golden setae oriented forwards, cut and flattened on top and there also widest. Setae on middle antennomeres as long as ½ length of antennomeres; antennomeres 2–11 combined twice longer than pronotal width; antennomeres 2 and 4–9 elliptical, antennomere 3 club-shaped, antennomere 10 trapezoidal, terminal antennomere cut latero-apically; antennomere 10 longest and widest, all antennomeres wider than long, antennomere 3 only 1.1 times longer than antennomere 4; length ratio of antennomeres 2–11 100: 175: 163: 144: 144: 144: 144: 144: 194: 106, width ratio 181: 200: 231: 231: 231: 225: 225: 231: 263: 181.

Pronotum longer than wide (1.09), widest in anterior third; width ratio of head/anterior edges of pronotum / widest point of pronotum / posterior edges of pronotum 100: 74: 87: 69. Anterior corners obtusely rounded, not protruding and with small teeth. Posterior corners almost rectangular. Pronotal base convex.Anterior margin very finely convex, in middle very finely concave. Lateral margin cordiform, with fine teeth. Pronotum laterally arched, with mid-longitudional impression, latter slightly widened backwards. Punctation dense and large as on head, rounded. Punctures almost touching each other, in impression joined, interspace wrinkled. Punctures with yellow, forward-oriented setae. Setae as long as puncture diameter and fine. Around impression, on anterior margin and on lateral margins setae distinct and two times longer than puncture diameter.

Elytra oval; 3.0 times longer and 1.8 times wider than pronotum, elytra length/width ratio 1.83. Base of elytra concave, narrower than pronotal base (0.84). Each elytron with 10 rows of punctures, 8 on dorsal side, 2 on deflexed part. Intervals 3, 5, 7 and 9 keeled, interval 7 flattened in first quarter, keels on top with teeth with yellow erected setae. Setae thin and sharp, twice longer than puncture diameter. Remaining intervals flat. Keels disappearing on the elytral declivity. Intervals not forming humeral corners, only basal tooth on keel is slightly bigger. Punctures deep, rounded and as large as those on pronotum, with fine setae as long as ¾ puncture diameter. Distance between punctures in row 1.5–2.0 wider than puncture diameters. Interspaces gently wrinkled. Epipleura with one row of punctures in its whole length, its punctures somewhat smaller than in row 10, smaller towards apex. Humeral calli not developed, apterous.

Legs finely covered with light adherent hairs. Tibiae in males with small inner subapical tooth (female tibiae unknown). Ratio of posterior tibia width/length 0.15.

Abdomen on all ventrites with small rounded punctures of the same diameter. Interspaces between punctures decrease backwards, equal to puncture diameter on anal ventrite. Ventrites with very fine setae twice longer than puncture diameter.

Aedeagus ( Fig. 42 ) length approximately 0.3 mm.

Diagnosis. Pseudochillus (M.) thailandicus sp. nov. can be distinguished from P. (M.) palawanus sp. nov. and P. (M.) indochinensis sp. nov. by thin, erected, long and sharp setae; punctures on elytra deep and distance between punctures in row 1.5–2.0 wider than puncture diameters; and occiput with mid-longitudinal impression. While P. (M.) palawanus has thick, erected setae; punctures on elytra more shallow and distance between punctures in row smaller than puncture diameters; occiput without impression. Pseudochillus (M.) indochinensis has very short and adherent setae on elytra; punctures on elytra shallow and indistinct; occiput without impression.

Etymology. Named after Thailand where the type species was collected.

Distribution. Thailand: Chiang Mai Province.

Figures

Figs 10–16. 10–12 – dorsal view:10 – Pseudochillus (Micropseudochillus) palawanus sp.nov., holotype♂, Philippines (Palawan); 11 – P.(M.) thailandicus sp. nov., holotype ♂, Thailand.; 12 – P.(M.) indochinensis sp. nov., paratype ♀, Vietnam. 13 – P.(M.) indochinensis sp. nov., tooth on clypeus; 14–15 – humeral corner: 14 – P.(Kaszabochillus) helferi sp. nov.; 15 – P.(Pseudochillus) bangaloreanus (Kaszab, 1981). 16 – P.(P.) bangaloreanus (Kaszab, 1981), punctures on epipleura. Scale bar = 4 mm (Figs 10–12).

Figs 17–26. Antenna. 17 – Indochillus cristatus Koch, 1941. 18 – Pseudochillus (Pseudochillus) bangaloreanus (Kaszab, 1981). 19 – P.(P.) aalbui sp. nov. 20 – P.(Kaszabochillus) andamanus (Kaszab, 1981). 21 – P.(K.) helferi sp.nov. 22 – Indostola kaengkrachanensis sp.nov. 23 – I.pulchella Medvedev, 1991.24 – Pseudochillus (Micropseudochillus) palawanus sp. nov. 25 – P.(M.) thailandicus sp. nov. 26 – P.(M.) indochinensis sp. nov. Scale bar = 1 mm.

Figs 27–36. Lateral view of head with eyes. 27 – Indostola pulchella Medvedev, 1991. 28 – I. kaengkrachanensis sp. nov.29 – Indochillus cristatus Koch, 1941. 30 – Pseudochillus (Pseudochillus) bangaloreanus (Kaszab, 1981). 31 – P. (P.) aalbui sp. nov. 32 – P.(Kaszabochillus) andamanus (Kaszab, 1981). 33 – P.(K.) helferi sp. nov. 34 – Pseudochillus (Micropseudochillus) palawanus sp. nov. 35 – P.(M.) thailandicus sp. nov. 36 – P.(M.) indochinensis sp. nov.

Figs 37–43. Aedeagus. 37 – Indostola kaengkrachanensis sp. nov. 38 – I. pulchella Medvedev, 1991. 39 – Pseudochillus (Pseudochillus) bangaloreanus (Kaszab, 1981). 40 – Pseudochillus (P.) aalbui sp. nov. 41 – Pseudochillus (Micropseudochillus) palawanus sp. nov. 42 – P.(M.) thailandicus sp. nov. 43 – P.(M.) indochinensis sp. nov. Scale bars: 0.5 mm (Figs 37, 38, 40–42), 1 mm (Fig. 39, 43).