Pterostichus phiaoc Fedorenko, 2019

Fedorenko, D. N., 2019, New species of Pterostichus subgenus Circinatus (Coleoptera: Carabidae: Pterostichini) from Vietnam, Russian Entomological Journal 28 (4), pp. 358-369 : 363-364

1. Pterostichus phiaoc Fedorenko , sp.n.

Figs 1 , 25 , 31–32 .

MATERIAL. Holotype ♂ ( ZMMU) and paratypes, 4♀♀ ( SIEE), labelled: ‘N-Vietnam, 40 km W of Cao Bang, Phia Oac Mt. , 22°36´25´´N / 105°52´08´´E, h~ 1650–1700 m, deciduous forest, 3– 11.X.2018, leg. D. Fedorenko’.

DIAGNOSIS. Distinctive from the consubgeners in having pronotum cordate, with sides deeply sinuate in front of right and sharp basal angles, and also in the combination of two discal elytral setae, posterolateral pronotal seta only present and inserted in basal angle, pronotum with lateral bead obliterate before base and two very shallow basal foveae; elytral base with humeral tooth and no lateral bead, meso- and metatarsomeres 1–2 with outer carina and sulcus, and metatrochanteral seta vestigial or missing.

DESCRIPTION. Body ( Fig. 1 ), BL 12.6–13.8 mm. Pronotum and elytra very slightly sericeous, with a trace of iridescence and hardly traceable microsculpture consisting of nearly indistinct, very small, moderately transverse meshes on pronotum while of very dense transverse lines on elytra.

Head: Frontal sulci shallow, subangulate or slightly convex posteromesad. Labrum subsinuate apically.

Pronotum cordate, i. e., nearly orbiculate, but for sides deeply sinuate just in front of and barely diverging towards right and sharp basal angles, PW/PL 1.08–1.11 (mean 1.09, n=5), PW/HW 1.53–1.58 (1.55). Base truncate or very gently oblique laterally, as wide as apex, PB/PA 0.96–1.0 (0.98); apex truncate or barely convex, apical angles slightly projecting and blunt. Disc convex and smooth; median line fine, obliterate basally and apically; basal and apical transverse impressions indistinct. Basal sulci shallow, inner sulcus longitudinal, running on basal 2/5, with very few fine punctures; outer one short, smooth and almost imperceptible. Lateral bead fine, obliterate before posterolateral seta, basal bead missing, apical bead shallow or interrupted just medially.

Elytra elliptic, EW/EL 1.57–1.64 (1.60), EW/PW 1.15– 1.20 (1.18), broadest about medially or just behind, rounded on sides, truncate apically combined, with widely rounded humeri, conspicuous humeral tooth and subtle preapical sinuation. Basal ridge subconvex apicad, humeral angle obtuse and sharp; basolateral bead obliterate. Striae deep, minutely to indistinctly punctate at bottom. Intervals slightly convex on disc, convex around. Parascutellar striole entire. Discal setae d2 and d3 2/5–1/2 or 2/3–3/5 distant from base, respectively. USS: 15–17.

Underside totally smooth, except for some fine punctures on basal two abdominal sternites. Prosternum with a fine yet distinct medial groove; prosternal process in lateral view rectangular and apically rounded; declivity flat near mesothoracic peduncle, with indistinctly beaded lateral edges, subconvex ventrally, rather wide in middle part. Metepisternum barely shorter than wide.

Legs: Meso- and metatarsomeres 1–2 carinate and sulcate laterally, sulcus on mesotarsomere 2 being vestigial. Metatrochanteral seta vestigial or missing, distal metafemoral seta missing.

Aedeagus ( Figs 25 , 31–32 ): apex of median lobe rounded in dorsal view, with nearly indistinct rounded tooth on right side just apical to a deep groove which is oblique to the right. Right paramere triangular, well sclerotized on left (inner) side, subsinuate before apex. Everted and inflated internal sac somewhat spiral, bent to the left and ventrad, with two spinose sclerites.

NAME. Toponymic noun, refers to the type locality .

DISTRIBUTION. Known from the type locality only, Mt. Phia Oac , northern Vietnam .

HABITATS AND HABITS. All specimens were hand collected under bark of rotten tree brunches on the ground in a cloudy broad-leaved forest.

Figures

Figs 1–3. Dorsal habitus: 1 — Pterostichus phiaoc sp.n., female paratype; 2 — P. caobang sp.n., holotype; 3 — P. expolitus sp.n., holotype. Рис. 1–3. Габитус дорЗально: 1 — Pterostichus phiaoc sp.n., паратип самка; 2 — P. caobang sp.n., голотип; 3 — P. expolitus sp.n., голотип.

Figs 21–30. Right paramere: 21–22 — Pterostichus phangxipang sp.n.; 23–24 — P. batxatensis sp.n.; 25 — P. phiaoc sp.n.; 26–27 — P. laocaiensis sp.n.; 28–30 — P. hoanglien sp.n.; 21, 23, 25, 26, 28–29 — left view; 22, 24, 27, 30 — ventral view. Scale bar: 1 mm. Рис. 21–30. ПраваЯ парамера: 21–22 — Pterostichus phangxipang sp.n.; 23–24 — P. batxatensis sp.n.; 25 — P. phiaoc sp.n.; 26– 27 — P. laocaiensis sp.n.; 28–30 — P. hoanglien sp.n.; 21, 23, 25, 26, 28–29 — слева; 22, 24, 27, 30 — вентрально. Масштаб: 1 мм.

Figs 31–36. Everted and inflated internal sac of aedeagus: 31–33 — Pterostichus phiaoc sp.n.; 34–36 — P. batxatensis sp.n.; 31, 34 — left view; 32, 35 — dorsal view; 33, 36 — right view. Scale bar: 1 mm. Рис. 31–36. Вывернутый и надутый внутренний мешок Эдеагуса: 31–33 — Pterostichus phiaoc sp.n.; 34–36 — P. batxatensis sp.n.; 31, 34 — слева; 32, 35 — дорЗально; 33, 36 — справа. Масштаб: 1 мм.