Heptodonta nigrosericea (W. Horn, 1930 ) Görn, Sebastian, 2020

Görn, Sebastian, 2020, Revision of the Oriental tiger beetle genus Heptodonta Hope, 1838 (Coleoptera: Cicindelidae), Zootaxa 4875 (1), pp. 1-62 : 19-20

Heptodonta nigrosericea (W. Horn, 1930) stat. nov.

Figs. 37–45

Odontochila (Heptodonta) analis nigro-sericea W. Horn, 1930: 9 .

Heptodonta analis nigrosericea . Wiesner, 1992: 69.

Syn. Heptodonta lumawigi Wiesner 1980: 121–123 , syn. nov.

Type locality. Philippines: Columbogan [Mindanao] .

Type material of H. nigrosericea . Lectotype (designated here): ♀ in SDEI, labelled: “Columbogan / Philip- pines / VII-VIII-1917 / G. Haslam” [handwritten] // “Carn. Mus. / Acc. 5950” [printed/handwritten] // “Carnegie Mus.” [handwritten] // “Type / W. Horn” [printed] // “ Syntypus ” [red, printed] // “Coll. DEI / Eberswalde” [printed] // “ Heptodonta / analis / nigrosericea / Horn” [handwritten] // “Coll W. Horn / DEI Eberswalde” [printed] // “ssp. / nigro-seri- / cea / m.” [yellow with black frame, handwritten] // “SDEI Coleoptera / # 301568” [printed] // “LEC- TOTYPE / Odontochila (Heptodonta) / analis nigro-sericea / W. Horn, 1930 / design. Sebastian Görn 2020” [red, printed] // “ Heptodonta / nigrosericea / (W. Horn, 1930) / det. Sebastian Görn 2020” [printed].

Type material of H. lumawigi syn. nov. Holotype: ♂ in JWCW, labelled: “ Philippinen, Iloilo / Canuawua, 5.78 / leg. R. Lumawig ” [yellow margin, handwritten] // “ Heptodonta / lumawigi m. / det. J. Wiesner 78” [hand- written] . Allotype: 1 ♀ in JWCW with same labels as holotype. Paratypes: 1 ♂ 1 ♀ in JWCW, 1 ♂ in BMNH, with same labels as holotype. 1 ♀ in SDEI with same labels as holotype plus: “Coll. DEI / Eberswalde” [printed] // “lumawigi / Wiesn.” [yellow with black frame, handwritten] // “SDEI Coleoptera / # 301574” [printed]. All type specimens labelled: “ HOLOTYPUS (ALLOTYPUS or PARATYPUS respectively)” [red, printed] // “ Heptodonta / nigrosericea / (W. Horn, 1930) / det. Sebastian Görn 2020” [printed] .

Diagnosis. Distinguished by the combination of mediolateral and anteroapical elytral impressions, and blackish colouration with blue-yellow lustre. Resembling H. abasileia sp. nov. and particularly H. halensis sp. nov. due to its impression pattern and silky shining surface, but clearly distinguished from both by dark-brown female labrum, and the usually much darker colouration lacking any greenish touch.

Redescription. Body size: Length 11.7–14.9 mm (without labrum), width 3.4–4.4 mm ( Figs. 37–38 , 44–45 ).

Dorsal surface of head blackish with a slightly blue, yellow, or bronze lustre. Frons transversely grooved. Vertex with concave striation, straight converging in transition to orbital plates. Orbital plates with fine convex striation, and with two setae on each side. Occiput with transverse grooves and a smooth anteromedian spot. Genae violetblue, glabrous and shallowly grooved. Clypeus glabrous, blue-green with some median bronze. Labrum with four setae, five apical teeth, and one lateral tooth on each side, three median teeth acute, third apical teeth often reduced, shape variable, male labrum rectangular and short (0.63–0.78 mm long, 1.48–1.80 mm wide, Fig. 39 ), testaceous, often with a dark margin, female labrum antero-triangular or three median teeth protruding (0.93–1.13 mm long, 1.45–1.88 mm wide, Fig. 40 ), dark-brown. Mandibles dark-brown to black with a dorsolateral testaceous strip. Labial and maxillary palpi testaceous with dark-brown to black terminal palpomeres, pre-terminal maxillary palpomere in males sometimes in females always dark-brown. Antennae slender, extending back over the first quarter of the elytra, metallic black, male pedicel testaceous at basal tip, scape with a single apical seta, antennomeres 3–4 with few scattered setae, antennomeres 5–11 finely and evenly pubescent.

Thorax entirely glabrous. Pronotum silky black with a blue-yellow and/or bronze lustre, median line moderately pronounced, proportions variable, pronotal length (2.28–2.93 mm) and width (2.18–2.83 mm) nearly identical, shallow transverse grooves, pronounced anterior and posterior sulci, anterior lobe wider than posterior, lateral margins of the median lobe moderately converging to the base. Episterna, sterna, and epimera violet-blue. Prosternum, posterior mesosternum, metasternum, and proepimeron with iridescent green to bluish-green lustre.

Elytra elongate, length 7.2–9.4 mm, slightly dilated laterally to almost parallel, maximal width posterior, silky black with a blue-yellow to bronze lustre, lateral margin and apex violet to bluish-green, juxtahumeral, discal, mediolateral, anteroapical, and apical impression considerably pronounced, impression on posterior declivity moderate or lacking, posterior gibbosity significant, basodiscal convexity moderate, blue punctures slightly decreasing in size from base to apex, punctures gently fused to transverse lines, converging to apex on anteroapical impression, basal and apical irregularly punctured.

Coxae dark-testaceous with iridescent green to bluish-green lustre, pro- and mesocoxae anteriorly, metacoxae laterally densely covered with long white setae, mesocoxae posterior with few white setae. Trochanters and femora testaceous. Femoral distal apices, tibiae, and tarsi metallic-black often with some gently violet lustre. Claws rufoustestaceous, basal slightly darkened.

Abdominal sternites glabrous (apart from few long setae at posterior margins, and some minute setae at posterolateral margin of sternite 5), dark-brown with faintly violet-blue to blue-green reflections, anal sternite with dark-testaceous apical margin ( Fig. 41 ).

Aedeagus arched, length 2.50–2.73 mm, medioventrally convex, dorsally curved, but dorsomedian often straight, apex slightly bent ventrally, with round tip and convex dorsal aspect, aedeagal base rather short and comparatively moderately sloping. Inner sac in left lateral aspect medioventral with elongate vertical sclerite and median with short horizontal sclerite, and in right lateral aspect with a spiny dorsoapical sclerite protruding from the apical orifice ( Figs. 42–43 ).

Variability. Pronotal and aedeagal shape show some variation, without losing the species-specific characters.

Distribution. Southern PHILIPPINES (Mindanao).

Additional material examined. 69 specimens. PHILIPPINES: Mindanao: Mt.Apo , X.2010, I.2011 ( JWCW) ; Gingoog , 8.5°N, 125.0°E, IV.1984 ( JWCW) ; Mt. Kintaniad , X.2014 ( JWCW) ; Bukidonon, Kabanglasan , X.2015 ( PSCH) ; Lanao Del Sur, Wao , IV.2017, VII.2017 ( PSCH) ; Bukidnon, Intavas , VIII.2014 ( SGCH) ; Surigao ( MNB) ; Bukidnon, X.1984 ( ZSM) ; Silipon , Bukidnon, 26.V.1932, 24.VI.1932 ( SDEI) .

Biology. Cabras & Wiesner (2016) reported that H. lumawigi syn. nov. occurs in secondary forest on shaded dark rocks near the river. Further, H. nigrosericea seems to be sensitive to human disturbances, preferring areas with rich vegetation cover.

Remarks. Only recorded from Mindanao, with one uncertain exception ( Horn 1930; Wiesner 1980, 1992; Cassola 2000; Cabras & Wiesner 2016; Cabras et al. 2016). The record from Panay ( Wiesner 1980) is probably the result of a confusion: before his collection trip to Panay in 1978, Lumawig also collected tiger beetles at Mt. Apo on Mindanao in 1974. Since 24 further specimens of H. nigrosericea were collected in 2010 and 2011 at Mt. Apo, this species seems to be quite common in that locality. As all additional material examined comes from Mindanao, and also the yet unclear record position of the type specimens “Columbogan” is actually located on Mindanao (see Munroe 1958), H. nigrosericea is probably endemic to that island.

Figures

FIGURES 37–43. Heptodonta nigrosericea (W. Horn, 1930): 37, 39, 41–43—♂, Philippines, Mindanao, Mt. Apo (JWCW): 37—habitus, 39—head, 41—lateral body, 42—aedeagus in left lateral aspect, 43—aedeagus in right lateral aspect; 38, 40—♀, Philippines, Mindanao, Mt. Kintanlad (JWCW): 38—habitus, 40—head. Scales: 37–41 = 1 mm, 42–43 = 0.5 mm.

FIGURES 44–47. 44–47—habitus: 44–45—Heptodonta nigrosericea (W. Horn, 1930): 44—♀, lectotype, Philippines, [Min- danao], Columbogan (SDEI); 45—♂, holotype of syn. H. lumawigi Wiesner, 1980, Philippines, Canuawua (JWCW). 46—H. melanopyga (Schaum, 1862), ♂, lectotype, Philippines, Luzon (MNB). 47—H. mindoroensis Cassola, 2000, ♂, Philippines, Mindoro, Mt. Halcon (JWCW). Scales: 1 mm.