Nebria (Epinebriola) incarinata, C.Huber & J.Schmidt, 2017

Huber, Charles & Schmidt, Joachim, 2017, Notes on the Nebria subgenus Epinebriola K. DANIEL, 1904 with the description of Barbonebriola subgen. nov. and 13 new species from the Himalaya-Tibet orogen (Coleoptera, Carabidae, Nebriini), Contributions to Natural History 36, pp. 1-85 : 72-78

publication ID	https://doi.org/ 10.5169/seals-787049
DOI	https://doi.org/10.5281/zenodo.6315682
persistent identifier	https://treatment.plazi.org/id/03948799-FF9C-FF8D-FF24-FB62FB9DFB6E
treatment provided by	Carolina
scientific name	Nebria (Epinebriola) incarinata
status	sp. nov.

Treatment

Nebria (Epinebriola) incarinata View in CoL sp. nov. ( Fig. 39 View Fig )

Holotype ♂: India, Arunachal Pradesh, Sela Pass , 27°30'12" N, 92°06'16" E, 4200–4500 m, 24./ 25. 6. 2008, leg. Reuter ( cSCHM). GoogleMaps

Body length 11 mm. Colour black. Head on vertex weakly brownish lightened. Appendages of the head brown. Antennae brown. Tibiae and tarsi brown.

Head supraorbitally with two shallow oblique impressions (which are faintly longitudinally wrinkled) between the eyes. Labrum with anterior margin straight, bearing six setae. Frons transversally wrinkled. Vertex impunctate. Eyes prominent. One supraorbital seta. Antennae long and slender extending at least to the middle of the elytra. Antennal scape cylindrical, elongate, longer than the eye's diameter, basally narrowed, with one dorsal seta. 2 nd antennomere with one seta ventroapically. Mandibular lamella longitudinally wrinkled. Maxillar palpomeres slender. Maxillary stipes laterally flat, with 5–6 long and fine setae. Penultimate labial palpomere trisetose. Ligula short, triangular, with two lateral setae. Mentum with a bifid medial tooth. Submentum with a row of 13 long and fine setae. Vertex impunctate. Microreticulation of the head isodiametric.

Pronotum transverse, ratio width/length of the pronotum = 1.39. Lateral margin widely rounded to the anterior angles, rectilinearly narrowed to the posterior angles ( Fig. 31I View Fig ). Anterior angles not protruding. Lateral explanation narrow with a shallow groove also apically, broadened basally. Lateral margin at the posterior angel obliquely upturned. Basal margin near angles deeply concavely arcuate. Posterior angles acutely projecting backwards. Pronotal disc weakly bulging. Basal fovea deep, anterior transverse impression weak, posterior transverse impression faint, median line shallow. Lateral groove, basal fovea, anterior transverse impression impunctate, the latter paramedially longitudinally wrinkled. Posterior transverse impression sparsely punctate. Apical margination of the pronotum restricted to lateral one-thirds, merges with the apex on the anterior angle. Base of the pronotum not margined. Basolateral seta present, in the holotype specimen at hand on both sides broken, visible only in lateral view as a short stub. Two midlateral setae in the apical half of the pronotum, inserted within the lateral groove. Pronotum impunctate on disc, Microreticulation isodiametric. Proepisternum smooth. Prosternal process triangular, laterally and apically unmargined.

Elytra: Elytral outline convex, regularly ovoid-elongate, widest slightly behind the middle. Ratio length/width of the elytra = 1.56. Elytral apex widely rounded, apical carina faint. Basal margin bent backwards towards the scutellum, arcuate craniad, obtusely merged with the lateral margination. Lateral margin of the elytra slightly rounded to the base. Humeral carina absent, instead of that a distinct incision towards the scutellum as basal margin of the epipleuron; no triangular carinal area ( Fig. 40 View Fig ). Distance between the humeral angles shorter than the distance between the pronotal posterior angles. Striae distinct but shallow, faintly punctate on disc, obliterate towards the apex. Intervals flat. 3 rd interval with 6–7 setae adjoining stria 3, 5 th interval with one seta on disc, 7 th interval asetose. Scutellar seta absent. Microreticulation isodiametric. Mesepisterna smooth. Metepisterna 1.8 times as long as wide, smooth. Metacoxa basally and apically unisetose.

Sternum 2 laterally smooth. Sternum 3 medially asetose. Sterna 4–6 each with 2 posterior paramedial setae. Anal sternum with two paramedial setae in the male. All sterna with faint impressions laterally.

Legs: Tarsi dorsally glabrous. In the male protarsomeres 1–3 conspicuously broadened, ventrally with pads of adhesive setae. Metatarsomere 4 with a long ventral tooth which is nearly as long as the tarsomere itself. Meso- and metatarsomeres 2–4 compact. Metatarsomere 5 ventrally with two rows of 2–3 short setae, longer than metatarsomeres 3+4.

Male genitalia: Edeagus large ( Fig. 20H View Fig ): Base of the median lobe small, with prominent basolateral lobes. Mid-shaft of the median lobe regularly curved at base, moderately at apex. Mid-shaft thin, apically bulbously thickened, apex deflected to the left. Apex in dorsal view broadened, tip of the apex triangular ( Fig. 20I View Fig ), short and wide. Mid-shaft of the endophallus without setae.

Female unknown.

Body ratios: hea.w/fro.w = 1.39; prm.w/hea.w = 1.27; prm.w/prp.w = 1.59; pra.w/prp.w = 1.07; ely.w/prm.w = 1.52; prm.w/prm.l = 1.39; ely.l/ely.w = 1.56.

Etymology: The specific epithet refers to the absence of the humeral carina.

Diagnosis: N. incarinata sp. nov. differs from all Epinebriola species by its unique humeral outline of the elytra due to the absence of the humeral carina.

Distribution ( Fig. 41 View Fig , Nr. 22): Known only from the type locality, the pass Sela in Western Arunachal Pradesh, India, east of the Bhutan border.

Habitat: Not noted.

Remarks to the taxonomic significance of characters of the female gonocoxae

Although some authors ( Shilenkov 1983, Kavanaugh & Shilenkov 1996, Shilenkov 1998, Huber & Schmidt 2007) repeatedly described and pictured female gonocoxae and pointed in such a way to a possible shape variability of the distal gonocoxite 2, in relevant literature ( Ledoux & Roux 2005) the value of female gonocoxae is not considered noteworthy due to their "high similarity" ("sont assez semblables"). The present study of female gonocoxae shows a wide shape variability of the gonocoxite 2, even in the small species group of the subgenus Epinebriola . The taxonomic value of the distal gonocoxite 2 obviously has been disregarded and unvalued up to now by the nebriologists.

Female genital structures are often used in taxonomic and phylogenetic studies in Carabidae ( Liebherr & Will 1998, Liebherr 2015, Ortuño & al. 2003), within the tribe Nebriini by Kavanaugh (1996) when separating a new Tribe Pelophilini for the genus Pelophila DEJEAN, 1821 . Gonocoxae of carabids are primarily unsegmented and unjointed (Arndt & al. 2005). They are viewed as plesiomorphic in the tribe Cicindini Bänninger ( Kavanaugh 1986, Kavanaugh & Erwin 1991). Some other basal grade carabid groups ( Opisthiini , Nebriini , Notiokasiini , Notiophilini , Pelophilini ) have females with the distal gonocoxite 2 either absent or fused with the proximal gonocoxite 1, in both cases synapomorphies ( Kavanaugh & Erwin 1991).

In terms of the gonocoxae the plesiomorphic condition seems to be unclear within the Nebriini . In Epinebriola and Barbonebriola subgen. nov. the continuous ventral sclerotization and the membranous dorso-median area of the gonocoxites may be of an ambiguous value, a character of incipient joint formation or of an uncompleted fusion. A similar feature is mentioned by Kavanaugh (1996) for the bispecific genus Pelophila , the sister group of the Nebriini , with the female gonocoxites fused medially and widely separated dorsally.

Moreover, in the present study the shape of the gonocoxite 2 seems to be an evolutionarily stable character within some species groups, which led us (in addition to other characters) to establish the new subgenus Barbonebriola . The female gonocoxite 2 as well as the maxillary stipes seem to comprise characters of high taxonomic and evolutionary significance also in genus Nebria .

Key to subgenera

Step 28 of the determination key to the subgenera of the genus Nebria View in CoL in Ledoux & Roux (2005) has to be changed in the following way:

28 Species of the Himalaya-Tibet orogen from Hindu Kush to SE Tibet. Sterna 4–6 polysetose. ................................................................................... 28a

– Species of Tian Shan to Kamar Daban including Dzungaria, the Tarbagatai, the Altai and the Sajan Mountains. Sterna 4–6 generally unisetose (exceptionally polysetose in N. setosa View in CoL , N. kaszabi View in CoL and N. murzini View in CoL ). ................................... subgenus Pseudonebriola View in CoL LEDOUx & ROUx, 1989

28a Maxillary stipes laterally berry-like bulging with tubercles bearing each a robust seta. ................................................... Barbonebriola subgen. nov.

– Maxillary stipes laterally normal, not berry-like bulging, only with robust setae. ........................................... subgenus Epinebriola K. DANIEL, 1904 View in CoL