Medina, Anichtchenko & Sciaky & Medina, 2022

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 : 60-62

Medina , sp. n.

( Figs. 5 , 10 )

Material: Holotype, male – “ Maguing, Lanao Del Sur, Mindanao | october 2018 ” ( DUBC) ; Paratype, female – “ Philippines, Mindanao | Mt. Apo | XI.2013 ” (cRS) .

Diagnosis. This species is very similar to H. andrewesi ; the diagnostic differences are listed under that species.

Description. Body length: 8.9–10.0 mm. Width/ length of head: 1; Width/length of pronotum: 1.06; length/ width of elytra: 1.7. Body, legs and palpi dark brown or uniformly black; antennae brown.

Head as long as wide, depressed, slightly narrower than the prothorax. Eye moderately large and markedly protruded, 0.75 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, last antennomere go beyond the middle lenght of pronotum; three basal antennomeres and basal half of antennomere 4 glabrous. Clypeus with two pores near anterior angles; with wide, transverse and rugate depression, clypeal suture very deep and complete; apical margin of clypeus straight. Labrum transverse and symmetric, slightly bisinuate apically. Frons with two large irregularly shaped, deep impressions. Posterior half of impressions rugate. Postorbital pore isolated. Surface with indistinct microreticulation, shiny. pore and completely obsolete in basal fifth.Anterior lateral seta situated at widest point, posterior lateral seta absent. Dorsal surface smooth, with very shallow transverse sulci. Microreticulation transverse and very fine.

Elytra elongate, markedly depressed, parallel sided. Base straight, humeri widely rounded; lateral margins straight. Basal margin concave, connected at an obtuse angle with lateral margin at position between striae 4 and 5. Scutellar stria long, not connected with first stria.All striae deeply impressed and almost smooth, impunctate. Intervals flat and smooth. Scutellar seta situated at base of stria 1. Interval 3 with three setiferous pores, the anterior pore situated in the 3rd stria at the level of apice of scutellar stria; the discal pore situated immediately behind the middle of elytra near second stria; posterior one situated in apical fifth, near the stria 2. Interval 5 of elytra with one pore. Marginal series consisting of 14–15 pores. Intervals impunctate and with well visible microreticulation, consisting of polygonal meshes, glossy.

Legs of average size. Three basal tarsomeres of all legs triangular and wide; dorsally with longitudinal rugosity, especially in mid­ and hind tarsa; tarsomere 4 wide and very deeply excised, with dense brush­like pilosity on ventral surface. Tarsal claws edentate.

Pronotum wider than head, widest at apical third, almost as long as wide; dorsal surface depressed. Anterior margin straight, anterior angles completely rounded. Lateral margins evenly curved, in basal fifth of the lenght parallel sided, with long sinuation before hind angles; basal angles right, not produced; base straight. Median line deep, impunctate, not reaching anterior margin of pronotum; anterior transverse sulcus obsoleted, posterior sulcus wide and shallow, connecting apices of very shallow basal grooves. Apex and base not margined, lateral borders narrowly margined, marginal sulcus slightly wider near lateral Aedeagus ( Fig. 10 ) elongate, ventral surface almost straight to apex. Apex of median lobe moderately long and slightly bent to the lower side. Endophallus with big semicircular sclerite.

Distribution. Known from two different localities of the island of Mindanao, one situated in the province of Lanao del Sur, the other in the province of Davao del Sur; probably it is widely diffused in the whole island of Mindanao.

Etymology. The specific epithet derives from the Latin “amicitia ” (fem.) – friendship, in allusion to significance of friendship and collaboration in science and life.

Affinities. This species is similar to H. andrewesi , although smaller. The overall aspect is very

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

similar, but some details ot the elytral punctuation, the different length/width ratio of the elytra, and shape of the head and of the pronotum allow to distinguish between the two.

Figures

Fig. 5. Habitus of Hexagonia amicitia sp. n. 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.