Hexagonia andrewesi JedliËka, 1935: 89

Anichtchenko, Alexander, Sciaky, Riccardo & Medina, Milton Norman, 2022, Taxonomic notes on the genus Hexagonia Kirby, 1825 with description of three new species from the Philippines (Coleoptera: Carabidae: Hexagoniini), Baltic Journal of Coleopterology 22 (1), pp. 55-66 : 57-58

Hexagonia andrewesi JedliËka, 1935: 89

( Figs. 1 , 7 )

014404850” & idem but “NHMUK 014404853” (BMNH).

Diagnosis. Very similar to H. amicitia sp. n., but different in the longer and more prominent temples; asymetric labrum; pronotum without lateral setiferous pores, slightly produced hind angles of pronotum and different length/width ratio of elytra. In addition it can be diagnosed by the presence of obtuse humeral angle and absence of setiferous pores in interval 5 of elytra.

Redescription. Body length: 11.5 – 12.0 mm. Width/length of head: 0.92; width/length of pronotum: 0.9; length/width of elytra: 1.7. Body, antennae and legs uniformly black or slightly brownish, palpi brown.

Type material: Holotype, male – “ Philippine Islands | Dingat Is. [Dinagat] | 163 | XII.1915 | Coll. Bottcher ”, “Philippine Is. | Coll. Bottcher | B.M. 1929­ 201”, “ Hexagonia | andrewesi | type sp. n. [handwritten]| det. Ing. JedliËka ”, “Type [round red label]”, “NHMUK 014404858” ( BMNH) . Paratypes, 2 ex – “Philippine Is. | Coll. Bottcher | B.M. 1929­ 201”, “ Hexagonia | andrewesi | sp. n. [handwritten]| det. Ing. JedliËka ”, “Cotype [round yellow label]”, “NHMUK 014404929” & idem but “NHMUK 014404872” ( BMNH) . Other material: 2 ex – “Philippine Is. | Coll. Bottcher | B.M. 1929­ 201”, “NHMUK Head with elongate hexagonal shape; dorsally depressed, slightly narrower than the prothorax. Eye moderately large and markedly protruded, 0.6 times as long as temples; temples not protruding; gradually rounded to the constriction of the neck. Mandibles elongate, slightly incurved in basal two thirds, then strongly incurved towards apex. Palpi elongate, narrowed towards apex, smooth. Mentum with wide triangular tooth, bisetose. Antenna relatively long, two apical antennomeres go beyond the middle lenght of pronotum; three basal antennomeres and basal half of antennomere 4 glabrous. Clypeus with two pores and two shallow pits, apical margin of clypeus slightly concave; clypeal suture very shallow and laterally effaced. Labrum transverse and strongly asymmetric, margin with wide triangular incision, right angle much longer than left. Frons with two deep, elongate, parallel sided pits. Postorbital pore isolated. Surface with indistinct microreticulation, shiny.

Pronotum wider than the head, widest at the middle, almost as long as wide; dorsal surface depressed.Anterior margin straight, anterior angles completely rounded. Lateral margins evenly curved, with short sinuation before hind angles; basal angles right, slightly produced; base of pronotum concave. Median line very narrow and moderately deep, impunctate, almost reaching anterior and posterior margins of pronotum;

Anichtchenko A., Sciaky R., Medina M.N.

anterior and posterior transverse sulcus obsoleted. Apex and base not margined; lateral borders narrowly margined, marginal gutter relatively wide in the middle part of pronotum. Lateral and posterior setiferous setae absent. Dorsal surface smooth, with hardly visible transverse microreticulation.

Elytra elongate, markedly depressed, parallel sided. Base straight, humeri with obtuse humeral angle; lateral margins straight. Basal margin concave, connected at an obtuse angle with lateral margin at position between striae 4 and 5. Scutellar stria long, but very effaced. All striae deeply impressed and smooth; sutural stria effaced near scutellum. Intervals flat and smooth. Scutellar seta situated at base of stria 1. Interval 3 with two setiferous pores, the anterior pore situated in stria 3 at the level of the end of scutellar stria; discal pore absent; posterior one situated in apical fourth, near stria 2. Marginal series widely interrupted in the middle, consisting of 9–10 pores. Intervals impunctate and with well visible microreticulation, consisting of polygonal meshes, glossy.

Legs of average size. Three basal tarsomeres of all legs triangular, very wide and dorsally smooth; tarsomere 4 wide and very deeply excised, with dense brush­like pilosity on ventral surface. Tarsal claws edentate.

Aedeagus ( Fig. 7 ) elongate, ventral surface almost straight to apex.Apex of median lobe moderately long and slightly downturned. Endophallus with big semicircular sclerite.

Female genitalia unstudied.

Distribution. This species known with certainty only from Dinagat island (Dinagat Islands prov., Caraga region). It is an island situated to the north­east of Mindanao. All the other known specimens bear generic labels mentioning only “ Philippine Islands ”.

Affinities. This species is similar to H. amicitia , although larger. The two share a similar general structure, but differ in the elytral punctuation, the length/width ratio of the elytra, and the shape of the head and of the pronotum. The only species, among those known to us, to which there two can be compared is H. nigrita Van de Pool, 1889 , widely diffused in south­east Asia from India to Indonesia, but not known from the Philippines.

Figures

Fig. 1. Habitus of Hexagonia andrewesi JedliËka, 1935, Holotype, male. Scale bar 5 mm.

Figs. 7–11. Aedeagus of Hexagonia, A – dorsal view, B – lateral view. 7 – H. andrewesi JedliËka, 1935, Holotype; 8 – H. castanea JedliËka, 1936 syn. n. Cotype; 9 – H. sauteri Dupuis, 1912, Holotype. Scale bar 1 mm. 10 – H. amicitia sp. n., Holotype; 11 – H. nigrocyanea sp. n. Holotype. Scale bar 1 mm.