Phaedis dilatitarsalis, Ruzzier & Ando, 2021

Ruzzier, Enrico & Ando, Kiyoshi, 2021, Seven new species of the genus Phaedis Pascoe, 1866 (Coleoptera: Tenebrionidae Cnodalonini) from Borneo, Zootaxa 4999 (5), pp. 439-455 : 443-446

Phaedis dilatitarsalis sp. nov.

( Figs 12–16 , 23 )

Type specimen. Holotype: ♀, Kina Balu , coll. Kraatz, Gebien det., Phaedis elysius Pasc., DEI Müncheberg , Col- 04767 ( SDEI).

Description. Female. Body length: 9.7 mm. Elongate, gently convex above, shiny. Colour dark reddish brown; dorsal surface reddish purple, the reddish purple colour on elytra being slightly changed into yellowish green depending on viewing angle; each elytron with a very ambiguous green spot at apical portion; mouthparts paler.

Head hexagonal, weakly convex above, finely microsculptured, with punctures fine, dense, not setiferous; mCG gently sinuate; epistoma slightly convex, produced forwards and depressed posteriorly, very feebly emarginate at apex in median two-thirds; frontoclypeal suture fine, slightly deepened anteriorly, not angulate at posterior corners; genae almost flat, nearly as wide as long, gently rounded at sides, weakly reflexed along outer margins; frons slightly, unevenly convex, not elevated along eyes; IE/TD 2.61; tempora very short, convex, roughened, not produced; eyes weakly transverse in dorsal view, with inner ocular sulci moderate in depth. Antennae moderate in length, reaching middle of pronotum; distal five antennomeres compactly articulate, distinctly dilated, forming club; 11th widest, short-oval. Mentum linguiform ( Fig. 12 ), longitudinally and broadly elevated in middle and deeply excavate at sides, with long setae anteriorly. Ultimate maxillary palpomere weakly securiform, with acute apical corners.

Pronotum transversely subquadrate, widest at middle, with fine isodiametric microsculpture; PW/PL 1.53; disc weakly convex, gently sloping laterally, finely sulcate before base, and not sulcate along lateral margins, with punctures dense and fine, larger than on frons; anterior margin slightly emarginate, very feebly beaded in each lateral fifth; lateral margins weakly and evenly rounded, slightly sinuate before base, thinly beaded; basal margin thickly beaded; anterior, posterior corners obtusely angulate, not produced. Scutellum triangular, slightly convex, densely microsculptured, with some microscopic punctures.

Elytra elongate, gently divergent posteriad, widest before apical third, weakly wider at base than pronotum, moderately convex, with fine isodiametric microsculpture; EL/EW 1.73; striae weakly impressed or vestigial in part; strial punctures coarse, dense though irregular in size, becoming more minute on apical declivity; intervals almost flat, finely and densely punctate; humeral callus oblong, weakly humped; epipleura weakly depressed, oblique, finely rugulose, scarcely punctate.

Prothoracic hypomera weakly convex, finely microsculptured, impunctate. Prosternum long, broad, weakly convex, densely microsculptured, impunctate; prosternal process wedge-shaped ( Fig. 13 ), horizontal, widely sulcate in middle, acute at apex, sparsely punctate. Mesoventral ridge U-shaped, ascendent forwards, with anterior angles acutely pointed in lateral view; anterior margins strongly emarginate in lateral view. Metaventrite gently convex, finely microsculptured, obliquely rugulose and microscopically punctate in middle. Abdomen weakly convex, densely covered with piligerous punctures.

Legs slender ( Figs 14–16 ). Femora weakly dilated towards apical third; profemoral teeth moderate in size, directed laterad at apex. Protibiae short, robust, gently incurved, with inner margins weakly emarginate between middle and basal sixth; meso-, metatibiae simple, weakly incurved. Basal three tarsomeres of pro-, mesotarsi, and basal two of metatarsi strongly, roundly dilated; penultimate tarsomeres short and small, embedded in antepenultimate tarsomere.

Male. Unknown.

Distribution. Borneo (Sabah).

Etymology. The specific epithet is derived from the dilated tarsi of this new species.

Differential diagnosis. This new species resembles Phaedis obtusidens Ando, 2019 from Sumatra in having similar form of elytra and tibiae but it is distinctly different from the latter by the characters mentioned in the following key.

- Relatively small (body length 9.7 mm); dorsal surface reddish purple; each elytron with an ambiguous green spot at apical portion; head with punctures neither setiferous nor oblong on frons; mCG gently sinuate; epistoma faintly emarginate at apex in median two-thirds; genae nearly as long as wide. Pronotum widest at middle, with punctures larger than on frons; anterior margin slightly emarginate, not produced forwards in middle. Elytra with striae weakly impressed or vestigial in part; intervals almost flat, densely punctate. Hypomera impunctate. Prosternum impunctate; prosternal process wedge-shaped, horizontal. Mesoventral ridge U-shaped, with anterior angles acutely pointed in lateral view. Profemoral teeth moderate in size; inner margin of protibiae weakly emarginate between middle and basal sixth; basal three tarsomeres of pro- and mesotarsi, and basal two metatarsomeres strongly dilated, each penultimate tarsomere small, embedded in antepenultimate tarsomere............................................................................................ P. dilatitarsalis sp. nov.

- Relatively larger (body length 11.6 mm); head and pronotum dark metallic green, elytra purple, without apical green spot; head with punctures setiferous in part, and oblong on frons; mCG even, not sinuate; epistoma remarkably deeply emarginate at apex in median three-fifths; genae longer than wide. Pronotum widest at basal two-fifths, with punctures smaller than on frons; anterior margin weakly emarginate, slightly produced forwards in middle. Elytra with striae distinctly impressed; intervals weakly convex except 1st and 2nd ones, sparsely punctate. Hypomera with a few fine punctures. Prosternum obscurely punctate; prosternal process subparallel-sided, distinctly hooked behind coxae. Mesoventral ridge V-shaped, without anterior angles in lateral view. Profemoral teeth weak and small; inner margin of protibiae not emarginate; tarsi simple, not dilated; each penultimate tarsomere small, not embedded in antepenultimate tarsomere................................ P. obtusidens Ando, 2019

Figures

FIGURES 12–16. Phaedis dilatitarsalis sp. nov. —12, mentum;13, prosternal process; 14, protibia; 15, mesotibia; 16, metatibia. Scale bars: 0.3 mm for fig. 12; 0.5 mm for Figs 13–16.

FIGURES 17–23. Phaedis spp., habitus.—17, Phaedis nagaii sp. nov.; 18, Phaedis tenuifasciatus sp. nov.; 19, Phaedis fusivittatus sp. nov.; 20, Phaedis choui sp. nov.; 21, Phaedis amabilis sp. nov.; 22, Phaedis minusculus sp. nov.; 23, Phaedis dilatitarsalis sp. nov.