Amphimenes brunneus, Kirschenhofer, 1999

Fedorenko, D. N., 2019, A revision of Amphimenes (Coleoptera: Carabidae: Lebiini), Russian Entomological Journal 28 (3), pp. 233-250 : 249-250

The brunneus species group.

The group includes five apterous soil-dwelling species from northern Vietnam; they all share elytral seta d1 missing and seta d2 situated before middle, combined with elytral cross-striated sculpture strongly reduced to nearly indistinct in most species. Three species of the group are known based on female holotypes only.

3.11. Amphimenes (s. str.) femoralis Fedorenko, sp.n.

Figs 10 , 19–20 , 35 .

MATERIAL. Holotype ♀ ( ZMMU) and paratypes ♂, 4♀♀ ( SIEE), labelled: ‘N[orthern]- 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’.

DESCRIPTION. Body ( Fig. 10 ) apterous, small, BL 6.2– 6.7 mm, and shiny black. Head and pronotum slightly dull, sometimes indistinctly paler; clypeus entirely or in apical half, labrum, mouthparts, antennae, and legs reddish-yellow; femora infuscated except apically. Pronotal lateral margin barely translucent with brown red, reflexed lateral margins of elytra narrowly red, becoming reddish brown just inside. Microsculpture coarse, isodiametric on head and at middle of pronotum, nearly granulate around; elytral microsculpture very superficial, consisting of very transverse meshes that become isodiametric ones on explanate lateral margin. Elytral cross-striated sculpture vestigial, hardly traceable in basal 1/2–1/3, slightly more distinct close to base.

Head with slightly flattened eyes; genae about half as long as eyes. Posterior supra-ocular seta about 2/5 eye length distant from posterior margin of eye. Antennae surpassing pronotal base by about apical two antennomeres.

Pronotum cordate, broadest slightly more than a third from apex, less than a third wider than long, PW/PL 1.28– 1.31 (1.29, n=6), and half wider than head, PW/HW 1.48– 1.55 (1.51). Base a third wider than apex, PB/PA 1.29–1.39 (1.34), with median part about as wide as lateral lobes; these evenly rounded and slightly projecting, more rounded towards highly obtuse basal angles. Apex very deeply sinuate; apical angles porrect, slightly acute and blunt. Sides rounded, more so toward apical angles, distinctly sinuate before basal ones. Disc convex, explanate lateral margins strongly reflexed, very narrow before anterolateral seta, moderately and increasingly wide behind. Median line deep, reaching apex and not quite reaching base. Basal foveae rather small, round, deeper just in front of meeting point of basal median part and lateral lobes. Basal transverse impression deep. Paramedian foveae small, moderately deep to indistinct, situated about midway between median line and lateral margin 2/5 from apex.

Elytra broadly oval, a third longer than wide, EL/EW 1.31–1.41 (1.34), and two thirds wider than pronotum, EW/ PW 1.59–1.68 (1.66), broadest at middle, with evenly round- ed sides. Humeri distinct yet more or less widely rounded, posterolateral angles very obtuse and blunt. Apical truncature oblique and rather transverse, barely sinuate; apices mostly very obtuse combined and blunt. Striae deep; intervals convex basally and in apical fourth, slightly less convex to nearly flat in between. Interval 3 bisetose, D2/EL 0.42–0.55 (0.49, n=6×2), posterior discal seta close to apex.

Metepisternum short: ES3L/ES3W 0.86–0.89 (n=2).

Tarsomere 5 with one pair of ventral setae. In male, profemur a third from base with a large ventral tubercle; mesotibia 4-tuberculate along apical 2/5 inner margin.

Aedeagus median lobe ( Figs 19–20 , 35 ) slightly twisted and dilated before apical orifice because a conspicuous left ventrolateral bulge is present.

DIAGNOSIS. This species belongs to the brunneus - group that includes totally five species, being very similar to A. brunneus and A. kabakovi . The latter two species share unicoloured pale legs, being distinctive also in having either a weaker microsculpture on the head and pronotum ( A. kabakovi ) or the body smaller, with elytral apices more pointed combined, subrectangular ( A. brunneus ) vs. very obtuse. Differences between the three species in body proportions are subtle, yet not overlapped (Table).

DISTRIBUTION. Known from the type locality only.

NAME. Refers to the femora infuscated.

HABITATS AND HABITS. An apterous soil-dwelling species occurring under smaller tree fragments on the ground and sharing these habitats with the sympatric species A. reflexicollis .

COMMENTS. Relationships between A. brunneus , A. kabakovi and A. femoralis sp.n. are obscured by their great similarity and the males unknown for the former two. More material is required to clarify whether they are species or subspecies, or conspecific.

Figures

Figs 6–10. Dorsal habitus: 6 — Amphimenes acutipennis sp.n., ♂ paratype from Kon Plong District; 7 — A. basipunctatus sp.n., holotype; 8 — A. tonkinensis sp.n., holotype; 9 — A. konplongensis sp.n., holotype; 10 — A. femoralis sp.n., ♂ paratype. Рис. 6–10. Габитус дорЗально: 6 — Amphimenes acutipennis sp.n., паратип ♂ иЗ округа Конплонг; 7 — A. basipunctatus sp.n., голотип; 8 — A. tonkinensis sp.n., голотип; 9 — A. konplongensis sp.n., голотип; 10 — A. femoralis sp.n., паратип ♂.

Figs 11–20. Median lobe of aedeagus: 11–12 — Amphimenes acutipennis sp.n.; 13–14 — A. similis sp.n.; 15–16 — A. guttatus; 17– 18 — A. basipunctatus sp.n.; 19–20 — A. femoralis sp.n.; 11, 17, 19 — left aspect; 13, 15 — left ventrolateral aspect; 12, 18, 20 — right aspect; 14, 16 — right ventrolateral aspect. Scale bars: 0.5 mm. Рис. 10–19. СреднЯЯ долЯ Эдеагуса: 11–12 — Amphimenes acutipennis sp.n.; 13–14 — A. similis sp.n.; 15–16 — A. guttatus; 17–18 — A. basipunctatus sp.n.; 19–20 — A. femoralis sp.n.; 11, 17, 19 — слева; 13, 15 — слева и сниЗу; 12, 18, 20 — справа; 14, 16 — справа и сниЗу. МасШтаб: 0,5 мм.

Figs 31–38. Median lobe of aedeagus, ventral aspect: 31 — Amphimenes acutipennis sp.n.; 32 — A. piceus; 33 — A. basipunctatus sp.n.; 34 — A. subcostatus sp.n.; 35 — A. femoralis sp.n.; 36 — A. marginicollis sp.n.; 37 — A. bicoloripes sp.n.; 38 — A. konplongensis sp.n. Scale bars: 0.5 mm. Рис. 31–38. СреднЯЯ долЯ Эдеагуса, вентрально: 31 — Amphimenes acutipennis sp.n.; 32 — A. piceus; 33 — A. basipunctatus sp.n.; 34 — A. subcostatus sp.n.; 35 — A. femoralis sp.n.; 36 — A. marginicollis sp.n.; 37 — A. bicoloripes sp.n.; 38 — A. konplongensis sp.n. МасШтаб: 0,5 мм.