Platymetopus tritus Bates, 1889

Kataev, Boris M., 2023, A review of Asian species of the genus Platymetopus (Coleoptera: Carabidae: Harpalini), Zootaxa 5306 (5), pp. 501-536 : 521-524

Platymetopus tritus Bates, 1889

( Figs. 42 , 46, 47 , 57, 58 , 65 )

Platymetopus tritus Bates, 1889: 270 . Type locality: “ Saigon, Mytho ”, Vietnam.

Type material examined. Syntype: female, with labels “ Saigon ”, “ Platymetopus tritus Bates ” [Bates’ handwriting], and “Ex Musaeo H.W. Bates, 1892 ” ( MNHN) .

Additional material examined. 1 female, with round piece of golden paper and labelled: “India orient.”, “ indicus Motsc. , India [Ménétries’ handwriting]” (this species never been described) ( ZIN). Myanmar. Kachin : 1 female, road Bhamo to Shwegu, Irrawaddy River , 157 m (light), 24°07′387″N 97°01′577″E, 5.VI.2006, M. Langer, S. Naumann & S. Löffler leg. (cWR). Tanintharyi : 2 males, 1 female, “Mus. Pragense, Tenasserim, Coll. Helfer ”, “ Platymetopus tritii Bates, Andrewes det.” ( ZIN). Vietnam. Hai Duong : 1 male, “Sept—Pagodes [= Pha Lai] (Tonkin)” ( ZIN). Quang Binh : 1 female, mts SW of Dong Hoi, 200 m, 27.XI.1961, O. Kabakov leg. ( ZIN). Gia-Lai : 1 male, Ankhi Distr., Buoenloy Vill. , 5–10.XI.1993, Yu. Starikov leg. ( ZIN). Dong Nai : 3 males, 6 females, Nam Cat Tien Nat. Park , at light HQL450, 30.V.–12.VI.2005, D. Fedorenko leg. (Exped. Russ. - Vietnamese Tropical Centre) ( SIEE, ZIN) ; 1 male, same data, but 27.X.2004 ( ZIN). Laos . 1 female, Borikhan Prov., 20 km N of Muang Paxan, Borikhan env., 18.V.2003, O. Šatranek leg. (cKM) ; 1 female, Luang Phaband Prov., Mt. Phou Phakhao, Namtap Vill. , 7–11.VI.2010, Sasa Kamphilavong leg. (cDST) ; 3 males, 2 females, Vientiane Prov. , Phou Khao Khouay , 18°20.369′N 102°48.523′E, 700–800 m, near strongly disturbed primary rainforest on light, 25–30.V.2008, A. Solodovnikov & J. Petersen leg. ( ZMUC) ; 1 male, Xaysomboun, Ban San Tong , VI.2015, Wang leg. (cZR). Thailand. Kamphaeng Phet : 1 male, Mae Wong National Park , 187 m, at light, 15°53.7′N 99°20.7′E, 9.VIII.2009, V. Zinchenko & A. Korshunov leg. ( ISEN). Bangkok : 1 male, Bangkok , Rajitani Villa, Clong Luang, 20.XII.2007 – 10.I.2008, A. Korshunov leg. ( ZIN). Nakhon Ratchasima ( Korat ) : 1 male, near Nong Bun Nak Vill., 220 m, 14°41′N 102°27′E, leaf-falling gallery forest, 27.VII.–2.VIII.2009, A.V. Korshunov leg. ( ZIN). Lan Sak : 6 males, 2 females, 25 km NW Lan Sak, 65 km NW Uthai Thani, VI.1990, Thielen leg. ( NME, cJS, ZIN). Phetburi : 1 female, Bon Kaeng Krachan , 30–31.VII.1996, M. Mostovsky leg. ( MPU). Chiang Mai : 1 male, Chiang Mai , 6.V.1988 (cWR).

Malaysia. Pahang: 1 male, 50 km NE Kuala Rompin, Endau Rompin N. P., G. Kerjung (Kg. Tebu Hitam), 400 m, at light, 9–30.IV.2008, P. Čechovsky leg. (cWR) .

Description. Body length: 6.1–7.5 (m 6.9) mm. Body proportions in Table 1 . Habitus as in Fig. 42 .

Body blackish brown to black, with unicolorous elytra; dorsum shiny, with metallic bronze or coppery tinge; base of mandibles and labrum occasionally paler. Palpi, antennae from apical part of antennomere 2 or 3 and tarsi blackish brown to black; basal antennomeres (2 and 3 at least partially), femora and tibiae brownish yellow; tibiae often slightly infuscate apically.

Head with large convex eyes; tempora oblique, flat; genae slightly wider than antennomere 1. Labral apex almost shallowly concave at middle. Supraorbital pore small, located close to supraorbital suture slightly before of level of posterior margin of eye. Frons and vertex densely and rather coarsely punctate, without microsculpture between punctures. Mandibles short, with almost straight mesal margin apically. Antennae long, surpassing pronotal basal margin; antennomeres 4–8 elongate, about two times as long as wide.

Pronotum comparatively wide, widest slightly before middle. Sides rounded in apical half, almost rectilinear in basal half; lateral bead complete, very narrow throughout; lateral furrow very narrow and shallow, recognized only in apical half; medial lateral seta inserted slightly before widest point. Apical margin deeply and more or less arcuately emarginate, bordered along entire length. Apical angles markedly prominent anteriorly, very narrowly rounded at apex. Basal margin longer than apical margin, shorter than elytral base, distinctly bordered along entire length, ciliate. Basal angles obtusangular, generally with a tiny obtuse denticle at apex. Disc convex, markedly depressed laterobasally. Basal foveae wide and moderately deep, outlines indistinct, fused with shallower laterobasal depressions. Median line roughly engraved, short, markedly not reaching anterior and basal margins. Anterior and posterior transverse depressions wide and shallow. Surface coarsely rugose-punctate, with coarsest punctures in basal foveae and laterobasal depressions, without microsculpture.

Elytra elongate oval, widest behind middle, convex on disc and somewhat gently sloping to apex. Humeri slightly prominent, rounded, generally with a tiny acute denticle visible behind, sometimes denticle absent. Lateral margins smooth along entire length. Preapical sinuation deep and long; sutural angle acutangular, narrowly rounded at tip. Basal border slightly sinuate, forming a very obtuse angle with lateral margin. Striae either superficial or slightly impressed apically or along entire length, coarsely punctate anteriorly, gradually becoming smooth behind middle. Intervals either equally wide and somewhat flat or intervals 3, 5 and 7 slightly wider and slightly more convex than neighboring. Discal setigerous pores absent. Marginal umbilicate series more or less clearly divided in basal and apical groups, each consisting of 5–7 setigerous pores. Punctation fine and dense, with three to five punctures across each interval in its middle portion. Microsculpture present throughout, consisting of slightly transverse meshes.

Prosternal process bordered. Proepisternum coarsely punctate. Metepisternum narrow, much longer than wide, strongly narrowed posteriorly. Wings fully developed.

Metatarsus slender, in both sexes longer than HWmin and shorter than HWmax, moderately densely setose ventrally. Male pro- and mesotarsomeres 1–4 only slightly dilated, each with adhesive vestiture.

Apex of abdominal sternite subtruncate or slightly concave in male and rounded in female, in both sexes with two pairs of marginal setigerous pores.

Female genitalia ( Figs. 57, 58 ): laterotergite with more or less sclerotized apex and with one apical seta; distal mesal angle of gonosubcoxite not prominent posteriorly, with a long seta at apex; gonocoxite about as long as gonosubcoxite, with two short thin seta on dorsal ridge of outer side.

Median lobe of aedeagus ( Figs. 46, 47 ) similar to that of P. flavilabris , but with apical portion in lateral view slightly more strongly curved ventrally and less sharply bent at apex and without a ventroapical denticle; terminal lamella in dorsal view rather evenly narrowed apically; internal sac without spines.

Comparison. This species shares most of its distinctive characters with P. flavilabris , particularly with the subspecies P. f. punctulatus , which also has brownish yellow femora and tibiae and a coarsely rugose-punctate pronotum without microsculpture. Platymetopus tritus differs from it in having the pronotum less strongly narrowed basally, with more or less rectilinear (never rounded) sides in front of the less obtuse basal angles and on average the smaller body size; in addition, the median lobe of P. tritus in lateral view is more arcuate, with less sharply bent apex and without a ventroapical tubercle, and the female genitalia are with a gonocoxite longer, about as long as a subcoxite.

In size and general habitus, P. tritus is somewhat similar to the sympatric P. rugosus , but distinctly differs from it in having body narrower with more strongly prominent apical angles of pronotum, basal antennomeres not infuscate, elytral lateral margin not serrate basally, genae wider, and median lobe of aedeagus less bent apically and without a spine in internal sac.

Distribution ( Fig. 65 ). This species was described from specimens collected in Southern Vietnam (Saigon and My Tho). Andrewes (1930) recorded it from Tenasserim ( Myanmar) and Hong Kong. According to our data, P. tritus is distributed over Myanmar, Vietnam, Thailand, Laos, West Malaysia, and Southeast China ( Hong Kong),

Figures

FIGURE 65. Platymetopus tritus Bates, 1889, distribution (black circles, based on examined material; white circles, based on literature data).

FIGURES 42–45. Platymetopus spp., habitus (42, 43, 45) and humerus (44). 42, P. tritus Bates, 1889 (Vietnam); 43, P. rugosus rugosus (Nietner, 1857) (India); 44, 45, P. r. obscurofemoratus subsp. n. (Vietnam, holotype). Scale bars = 1.0 mm (A: 44, B: 42, 43, 45).

FIGURES 46–56. Platymetopus spp., median lobe of aedeagus. 46, 47, P. tritus Bates, 1889 (Vietnam); 48, 49, P. rugosus rugosus (Nietner, 1857) (India); 50, 51, P. r. obscurofemoratus subsp. n. (Vietnam, holotype); 52, 53, P. quadrimaculatus Dejean, 1829 (Vietnam); 54–56, P. figuratus pictus Andrewes, 1923 (India, Rajasthan). Dorsal (46, 48, 50, 52, 54) and lateral (47, 49, 51, 53, 55, 56) views. Scale bars = 1.0 mm (A: 46–53, B: 54–56).

FIGURES 57–64. Platymetopus spp., gonocoxite, lateral view (57, 59, 61, 63), and laterotergite, gonosubcoxite, and gonocoxite, ventral view (58, 60, 62, 64). 57, 58, P. tritus Bates, 1889 (Vietnam); 59, 60, P. rugosus (Nietner, 1857) (India); 61, 62, P. quadrimaculatus Dejean, 1829 (Vietnam); 63, 64, P. figuratus pictus Andrewes, 1923 (India, Rajasthan). Scale bar = 0.5 mm.