Hexagonia sauteri Dupuis, 1912: 308

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 : 58-60

Hexagonia sauteri Dupuis, 1912: 308

( Figs. 2–3 , 8–9 )

Hexagonia castanea JedliËka, 1936: 55 syn. n.

Type material: Holotype, male – “Kankau [= Hengchun] | Formosa | Sauter IV.09”, “ Ex. Deutsch | Ent. Mus”, “ H.E. Andrewes Coll. | B.M. 1945­ 97”, “ Hexagonia | sauteri | Dupuis [handwritten]”, “ Dupuis det”, “Typus [red label]”, “NHMUK 014404802” ( BMNH) . Paratype, 1 ex – “ Formosa | Kankau IV.09 | Sauter”, “ Ex. Coll. Berl. | Zool. Mus.”, “Cotype [green round label]”, “ Hexagonia sauteri | det. P. Dupuis 1913”, “ H.E. Andrewes Coll. | B.M. 1945­ 97”, “NHMUK 014404769” ( BMNH) . Holotype – “ Type [red round label]”, “ Philippine Islands | Manila | 6.II.1914 | Coll. Bottcher ”, “Philippine Is.| Coll. Bottcher | B.M. 1929­ 201”, “ Hexagonia | castanea sp.n. | det. Ing. JedliËka [red label]”, “NHMUK 014404930” ( BMNH) . Paratypes, 5 ex – “ Cotype [yellow round label]”, “ Philippine Islands | Manila | 6.II.1914 | Coll. Bottcher ”, “Philippine Is.| Coll. Bottcher | B.M. 1929­ 201”, “ Hexagonia | castanea sp.n. | det. Ing. JedliËka ” ( BMNH). 2 ex – “Kankau | Formosa | Sauter IV.09”, “ Dupuis det”, “Typus [red label]”, “ Hexagonia sauteri | Dupuis”, “ Syntypus [red label]”, “DEI Coleoptera | # 200406”; idem but “DEI Coleoptera | # 200407” ( SDEI) .

Other material: 1 ex – “Philippine Is., Coll. Bottcher, B.M. 1929­ 201”, “NHMUK 014404905” ( BMNH); 1 ex female – “ Philippines, E Luzon | Sierra Madre, Aurora | Dingalan III.2016 ” (cRS)

Diagnosis. Instantly recognizable among all other oriental species of the genus by the combination of bifid mentum, short and wide mandibles, and several pores in elytral intervals 3 and 5.

Redescription. Body length: 8.3­ 9.5 mm. Width/ length of head: 1.27; width/length of pronotum:

Taxonomic notes on the genus Hexagonia Kirby, 1825 with description of three new species from the Philippines...

1.17­ 1.2; length/ width of elytra: 1.45­ 1.56. Body uniformly brown, sometimes tibiae, sides of elytra and mandibles slightly darker.

Head trapezoid, dorsally depressed, narrower than the prothorax. Eyes large and markedly protruded, almost as long as temples; temples protruding; gradually rounded to the constriction of the neck. Neck constriction well marked, narrow and deep. Mandibles relatively short, wide and gradually incurved towards apex. Palpi elongate, narrowed towards apex, smooth. Mentum bifid, bisetose. Antenna relatively short, just reaching lateral pore of pronotum; three basal antennomeres and basal half of antennomere 4 glabrous. Clypeus with two pores and an irregular transverse depression, apical margin of clypeus slightly concave; clypeal suture very strong and deep, laterally effaced. Labrum transverse and slightly asymmetric, margin with wide rounded incision, right angle slightly longer than left. Frons with two deep and wide impressions, connected by a third weaker impression between them. Postorbital pore isolated. Surface with indistinct microreticulation, shiny.

Pronotum much wider than head, markedly transverse, widest near apical third; dorsal surface depressed.Anterior margin slightly concave, ante­

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

rior angles completely rounded. Lateral margins form a slight and obtuse angle opposite the lateral setiferous pore; with evident excision before hind angles; basal angles right and moderately produced; base of pronotum straight. Median line narrow and deep, impunctate, almost reaching anterior and posterior margins of pronotum; anterior and posterior transverse sulcus obsolete. Anterior margin and base not margined; lateral borders margined, marginal sulcus gradually widened from angles of pronotum to setiferous pore. Lateral setiferous pore situated in widest point of pronotum, posterior pore absent. Disc transversally rugose, with hardly visible transverse microreticulation.

Elytra elongate, markedly depressed, very slightly widened in apical half. Humeri rounded. Lateral margins straight. Basal margin oblique, connected at a very obtuse angle with lateral margin at position between striae 4 and 5. Scutellar stria long, not connected with stria 1. All striae deeply impressed and crenulate. Intervals flat and smooth. Scutellar seta situated at base of 1st stria. Interval 3 with 4–7 setiferous pores (usually 6–7), two anterior pores closely spaced and situated near stria 3 at the level of end of scutellar stria; the discal and apical pores irregularly placed in apical half. Interval 5 of elytra with 2 pores, asymmetrically and irregularly placed in apical half. Marginal series consisting of 12–14 pores. Intervals impunctate and with well visible squamiform microreticulation, glossy.

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

Median lobe of aedeagus ( Figs. 8–9 ) elongated, apical third of median lobe slightly downturned. Endophallus with big semicircular sclerite.

Female genitalia unstudied.

Taxonomic notes. After careful study of type material of H. sauteri Dupuis, 1912 and H. castanea JedliËka, 1936 no differences were found between the two species. The new synonymy is established here.

Distribution. China, Japan (Ryukyu Islands), Taiwan, Philippine Islands: Luzon.

Affinities. This species seems rather isolated within the genus in the rather short and wide elytra, crenulate striae and several points on intervals 3 and 5. Beyond this, it is the only species known to day from an island different from Mindanao.

Figures

Figs. 2–3. Habitus of Hexagonia. 2 – H. sauteri Dupuis, 1912 Holotype, male; 3 – H. castanea JedliËka, 1936 syn. n., Cotype, 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.