Kenyacus parvus, Kataev, 2019

Kataev, Boris M., 2019, A review of the Afrotropical genus Kenyacus (Coleoptera: Carabidae: Harpalini) from the Rwenzori Mountains, with description of seven new species, Zootaxa 4679 (3), pp. 463-498 : 475-478

Kenyacus parvus sp. n.

( Figs 16, 20 , 28, 29 , 32–39 , 50b )

Type material. Holotype: ♂, “ UGANDA, Western Region, Kasese District, 15 km NWW Nyakalengija, Rwenzori Mts. National Park, env. of John Matte Hut , 0°23.189’N 29°55.307’E, accuracy 11 m, extent 100 m, h = 3447 m, Erica forest, sifting leaf litter [3566] [Garmin 60CSx; WGS84] V.I. Gusarov 12.viii.2008 U133” ( ZMUN).

Paratypes: 1 ♂, 4 ♀♀, same data as holotype ( ZMUN) ; 2 ♂♂, “ UGANDA, Western Region, Kasese Dis- trict, 15– 13.5 km NWW Nyakalengija, Rwenzori Mts. National Park, env. of John Matte Hut , 0°22.950–.972’N 29°55.305–.772’E, accuracy 3 m, extent 15 m, h = 3399–3403 m, sifting leaf litter [3565] [Garmin 60CSx; WGS84] H. Elven 12.viii.2008 U132” ( ZMUN, ZIN) ; 1 ♂, “ UGANDA, Western Region , Kasese District, 13.5 km NWW Nyakalengija, Rwenzori Mts. National Park , env. of John Matte Hut , 0°23.051’N 29°55.662’E, accuracy 6 m, extent 15 m, h = 3434 m, in tussocks of Carex runssoroensis [3563] [Garmin 60CSx; WGS84] V.I. Gusarov & H. Elven 11.viii.2008 U130” ( ZMUN) ; 4 ♂♂, “ UGANDA, Western Region , Kasese District, 13.5 km NWW Nyakalengija, Rwenzori Mts. National Park , env. of John Matte Hut, 0°23.206’N 29°55.719’E, accuracy 8 m, extent 8 m, h = 3532 m, Erica forest, sifting leaf litter [3559] [Garmin 60CSx; WGS84] V.I. Gusarov 11.viii.2008 U127” ( ZMUN, ZIN) ; 1 ♂, 1 ♀, “ UGANDA, Western Region , Kasese District, 13.5 km NWW Nyakalengija, Rwenzori Mts. National Park , env. of John Matte Hut, 0°23.112’N 29°55.806’E, accuracy 7 m, extent 5 m, h = 3457 m, Erica forest, sifting leaf litter [3557] [Garmin 60CSx; WGS84] V.I. Gusarov 11.viii.2008 U125” ( ZMUN) ; 6 ♂♂, 2 ♀♀, “ UGANDA, Western Region , Kasese District, 13.5 km NWW Nyakalengija, Rwenzori Mts. National Park , env. of John Matte Hut, 0°23.038’N 29°55.801’E, accuracy 7 m, extent 15 m, h = 3427 m, Erica forest, sifting leaf litter [3555] [Garmin 60CSx; WGS84] V.I. Gusarov 11.viii.2008 U123” ( ZMUN, ZIN, cWR) ; 2 ♂♂, 4 ♀♀, “ UGANDA, West- ern Region, Kasese District, 13.5 km NWW Nyakalengija, Rwenzori Mts. National Park , env. of John Matte hut, 0°23.001’N 29°55.774’E, accuracy 6 m, extent 20 m, h = 3421 m, Erica forest with mixed vegetation below, sifting leaf litter [3553] [Garmin 60CSx; WGS84] V.I. Gusarov 10.viii.2008 U121” ( ZMUN) ; 1 ♂, 1 ♀, “ UGANDA, Western Region , Kasese District, 12 km NWW Nyakalengija, Rwenzori Mts. National Park , main trail from John Matte Hut to Nyabitaba Hut , 0°22.801’N 29°56.711’E, accuracy 6 m, extent 15 m, h = 3241 m, Erica , Hypericum , bushes and grass, sifting leaf litter [3594] [Garmin 60CSx; WGS84] V.I. Gusarov 17.viii.2008 U160” ( ZMUN)

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Description (5 males and 5 females measured). Habitus as in Figs 28 and 29 . Body length 4.1–4.7 mm, width 1.8–2.0 mm.

Colour: Body dark brown, dorsal surface slightly shiny, ventral surface paler than dorsal; base of mandibles, labrum, clypeus, lateral margins of pronotum and elytra, as well as elytral suture reddish brown or brownish yellow; palpi, antennae and legs brownish yellow; antennae more or less markedly infuscate from antennomere 2 or 3.

Head: Comparatively large, in males HWmax/PWmax 0.78–0.79 (m = 0.79), HWmin/PWmax 0.57–0.67 (m = 0.64); in females these indices respectively 0.77–0.84 (m = 0.79), and 0.67–0.73 (m = 0.69). Eyes with large facets, slightly convex, separated from buccal fissure at distance of width of antennomere 1, HWmax/HWmin 1.18–1.21 (m = 1.19) in males and 1.11–1.19 (m = 1.15) in females. Tempora short, about quarter as long as eye, slightly convex or somewhat flat. Frons and vertex convex. Fronto-clypeal suture distinct, superficial or slightly impressed. Supraorbital setigerous pore located just behind level of posterior margin of eye, removed from supraorbital furrow at a distance of length of antennomere 2. Labrum almost straight anteriorly. Clypeus with slightly prominent apical angles and almost straight apical margin between them. Mentum and submentum fused, submentum with two setae on each side. Mandibles medium-sized; left mandible evenly bent in apical portion, with acute apex. Dorsal microsculpture in both sexes distinct throughout, consisting of isodiametric meshes. Antennae comparatively long, in both sexes slightly surpassing basal edge of pronotum, with antennomeres 7–9 longer than wide; in female antennae slightly shorter than in male, with slightly shorter antennomeres.

Pronotum: Slightly transverse, PWmax/PL 1.30–1.45 (m = 1.36), widest at the end of anterior third, strongly narrowed posteriorly, PWmax/PWmin 1.27–1.43 (m = 1.33); lateral seta inserted slightly before widest point. Sides rounded anteriorly, almost straightly converging from widest point to basal angles, without distinct border. Apical margin arcuately emarginate; apical angles slightly projecting ahead, acute, blunted or very narrowly rounded at tip. Basal margin slightly narrower than apical margin and noticeably narrower than elytral base, moderately emarginate, almost straight or slightly concave medially and rounded laterally; both apical and basal margins not bordered. Basal angles obtuse, narrowly rounded at tip, slightly projecting posteriorly. Disc moderately convex, more strongly sloped to apical angles, slightly depressed basally and flattened at basal angles, forming latero-basal depressions not distinctly delimited from other parts of disc. Lateral depressions beginning from apical angles as narrow furrows, slightly widened in basal half, reaching basal margin. Basal fovea somewhat shallow, reaching basal pronotal edge, usually fused with lateral depression at pronotal base and separated from it by small convexity anteriorly. Surface of pronotum impunctate. Anterior transverse depression variable, in most specimens distinct and long, slightly deepened. Median line thin, superficial, usually reaching apical and basal margins of pronotum. Microsculpture distinct throughout, consisting of large isodiametric meshes along basal and apical margins and of finer, slightly transverse meshes on remaining surface ( Fig. 16 ).

Elytra: Elongate oval, slightly widened posteriorly, widest just behind middle, in males EL/EW 1.40–1.44 (m = 1.42), EL/PL 2.59–2.86 (m = 2.76), EW/PWmax 1.38–1.40 (m = 1.39); in females these indices respectively 1.40–1.51 (m = 1.46), 2.63–2.87 (m = 2.74), and 1.37–1.44 (m = 1.40). Humeri prominent, evenly rounded at tip. Preapical sinuation very shallow, in many specimens sides in apical fifth rather sharply curved inside and then almost straightly converging to apex. Sutural angle in both sexes blunted or narrowly rounded at tip. Basal edge sinuate laterally, somewhat widely arcuately curving inside humerus up to lateral margin or forming with lateral margin a very obtuse angle. Lateral gutter distinct, narrow along entire length. Elytral disc convex in lateral and caudal views. Striae thin, impunctate, faintly crenulate, slightly impressed along entire length, their bases removed from basal elytral border. Parascutellar setigerous pore present, large. Parascutellar striole absent. Intervals slightly convex, almost not narrowed posteriorly; intervals 2 and 3 almost parallel-sided or slightly widened at apex; interval 3 without discal pore. Microsculpture distinct throughout, consisting of transverse meshes ( Fig. 20 ).

Ventral surface of thorax and abdomen: Prosternum with several moderately long erect setae medially and at apical margin. Metepisternum slightly wider than long, narrowed posteriorly. Basal abdominal sternites glabrous, two last visible (VI and VII) sternites sparsely pubescent, VI much more sparsely than VII; apex of last visible sternite with two pairs of marginal setae in both sexes, subtruncate or (mostly in female) with very shallow, indistinct incision at middle.

Legs: Metacoxae without any additional setae. Tarsi glabrous dorsally. Tarsomere 5 without setae ventrally. Meso- and metatarsomeres 1 about as long as meso- and metatarsomeres 2+3, respectively. Pro- and mesotarsomeres 2–4 of male slightly dilated (mesotarsi very faintly) and with biseriately arranged long adhesive scales ventrally; mesotarsomere 1 lacking adhesive vestiture ventrally; mesotarsomere 4 rather deeply emarginate.

Male genitalia: Median lobe ( Figs 32, 34, 35, 37 ) stout, rather strongly arcuate in lateral view, with large basal bulb; in dorsal view rather evenly narrowed distally in apical third. Terminal lamella in lateral view short, straight, without apical capitulum; in dorso-caudal view wide, narrowly rounded at apex and with rounded sides ( Figs 33, 36 ). Internal sac without any sclerotic elements, apical folding spiny patch long, reaching and usually penetrated in basal bulb.

Female genitalia: Very small ( Figs 38, 39 ); laterotergite (hemisternite) slightly asymmetrical, wide, membranous apically, without setae and spines. Basal stylomere elongate, with few very short setae apically. Apical stylo- mere elongate, slightly curved, slightly shorter than basal stylomere, with short thick seta at ventral edge of outer margin and with comparatively narrow base in ventral view; in lateral view narrowed to acute apex ( Fig. 38 ).

Etymology. The specific name is a Latin adjective meaning “little” and referring to the small body size of the new species.

Distribution ( Fig. 50b ). This new species is known from the Bujuku Valley in vicinity of John Matte Hut at altitudes of 3399–3457 m in the south-eastern part of the Rwenzori Mountains, where it occurs sympatrically with K. gusarovi sp. n., K. pusillus sp. n. and K. berndi sp. n.

Bionomics. According to the label data, the beetles were collected by sifting leaf litter in Erica forest and in tussocks of Carex runssoroensis ( Figs 93 , 94 ).

Comparison. In the body size (4.1–4.7 mm) and having moderately long erect setae along apical margin of prosternum, K. parvus sp. n. is similar to K. gusarovi sp. n., but distinctly differs from it in much slender body and in narrower pronotum (PWmax/PL 1.30–1.45 versus 1.52–1.56), with narrower base (PWmax/PWmin 1.27–1.43 versus 1.19–1.23) and with basal angles obtuser and narrowly rounded at tip ( Figs 28, 29 ). In addition, K. parvus sp. n. differs from K. gusarovi sp. n. in having left mandible with acute apex, median lobe of aedeagus with larger basal bulb ( Figs 34, 37 ) and female genitalia relatively smaller, with wider laterotergite ( Figs 38, 39 ). Differences between K. parvus sp. n., K. berndi sp. n. and K. trechoides sp. n. are described below under the two latter species.

Figures

FIGURE 50. Kenyacus, distribution. a, K. angustatus sp. n.; b, K. parvus sp. n.

FIGURE 93. Trail across the Bujuku river in vicinity of John Matte Hut (ca. 3400 m). Patches of Erica forest, edge of the Lower Bigo bog with tussocks of Carex runssoroensis, boulders covered with moss. Habitats of K. parvus sp. n. and K. gusarovi sp. n. Photo: Vladimir Gusarov.

FIGURE 94. Erica belt in vicinity of John Matte Hut (ca. 3400 m) near the type localities of K. gusarovi sp. n. and K. parvus sp. n. Habitat of K. gusarovi sp. n., K. parvus sp. n. and K. berndi sp. n. Photo: Vladimir Gusarov.

FIGURES 14–21. Kenyacus, microsculpture (14–17, male pronotal; 18–21, male elytral). 14, 18, K. ruwenzorii (Alluaud, 1917); 15, 19, K. gusarovi sp. n.; 16, 20, K. parvus sp. n.; 17, 21, K. angustatus sp. n. Scale bar = 0.2 mm.

FIGURES 28, 29. Kenyacus parvus sp. n., habitus, males (28, holotype; 29, loc. U123). Scale bar = 1.0 mm.

FIGURES 32–49. Kenyacus. 32–39, K. parvus sp. n. (32–34, holotype; 35–37, paratype, loc. U160; 38, 39, paratype, loc. U121); 40–46, K. berndi sp. n. (40–42, holotype; 43, 44, paratype, loc. U121; 45, 46, same, loc. U123); 47–49, K. trechoides sp. n. (holotype). 32, 35, 40, 47, median lobe, dorsal view; 34, 37, 42, 49, same, lateral view; 33, 36, 41, 48, apex of median lobe, dorso-caudal view; 38, 43, 45, stylus, lateral view; 39, 44, 46, laterotergite and stylus, ventral view. Scale bar = 0.5 mm.