Insulanebria Kavanaugh,, 2021

Kavanaugh, David H., Maddison, David R., Simison, W. Brian, Schoville, Sean D., Schmidt, Joachim, Faille, Arnaud, Moore, Wendy, Pflug, James M., Archambeault, Sophie L., Hoang, Tinya & Chen, Jei-Ying, 2021, Phylogeny of the supertribe Nebriitae (Coleoptera, Carabidae) based on analyses of DNA sequence data, ZooKeys 1044, pp. 41-152 : 41

Subgenus Insulanebria Kavanaugh, subgen. nov.

Reductonebria Shilenkov, 1975 (in part); = " Nebria carbonaria " group sensu Ledoux and Roux 2005

Type species.

Nebria carbonaria Eschscholtz, 1829:24, by present designation.

Diagnosis.

Body size small, SBL = 8.2 to 9.5 mm (1-2). Head width medium to slightly broadened, not constricted behind eyes; vertex with a pair of paramedial pale spots and a single pair of supraorbital setae (13). Eyes of moderate size, moderately to markedly convex. Antennal scape with one subapicodorsal seta; antennomeres 3 and 4 not laterally compressed, without extra setae. Labrum with three pairs of apical setae. Maxillary stipes typical for genus, with setae inserted flush on smooth surface. Penultimate labial palpomere with three setae. Pronotum with midlateral setae absent, a single pair of basolateral setae present. Elytral intervals smooth, without macrosculpture, interval 3 with five to eight or more setiferous pores, interval 5 without setae (except one seta present in a few specimens) and interval 7 with zero or two or more setiferous pores, intervals 3, 5 (if setose), and 7 (if setose) moderately catenate. Hindwings reduced to short membranous lobes with only vestigial venation evident. Metepisterna smooth, impunctate. Protarsomeres 1-3 expanded in males; mesotarsomeres 2-4 longer than their apical width; tarsi dorsally glabrous. Abdominal sternites IV-VI with two to four pairs of posterior paramedial setae, without paralateral setae. Median lobe of male aedeagus sclerotized dorsally at least to midlength on shaft, only faintly deflected right in dorsal aspect; basal bulb expanded, triangular or quadrate, broadly open basally and closed dorsally, without a sagittal aileron present at base or with only a lightly sclerotized collar; mid-shaft parallel-sided in lateral aspect, circular or only slightly compressed in cross-section, with right lateral face unmodified; apical orifice slightly to moderately deflected right. Right paramere slender and moderately long. Female valvifers without vestiture; gonopods VIII fused to dorsomedial bases of gonocoxae; gonocoxae with ventral diagonal row of setiform setae and mediodorsal row of setae present. Bursa copulatrix without dorsal sclerites in vestibular chamber and with longitudinal axis slightly arched basodorsally in lateral aspect; spermathecal chamber broadly cordate in dorsal aspect, and without dorsal or anterodorsal sclerites, insemination duct sclerotized as a long, narrow plate ventrally in the chamber; spermathecal duct slightly long, uniform in diameter throughout or nearly so, inserted sub-basodorsally on spermathecal chamber; spermathecal reservoir of medium length.

Etymology.

The subgeneric epithet is a noun of feminine gender and a combination of the Latin word, insula, meaning island, and the genus name, Nebria , in reference to the occurrence of both known species of this clade in Kuril Island Archipelago of far eastern Asia.

Remarks.

Members of this group are easily identified as members of the Reductonebria Complex using the Ledoux and Roux’s (2005) key to subgenera. They can be distinguished from members of the other two subgenera in this complex, Reductonebria Reductonebria and Reductonebria Erwinebria by several external and internal features. Most members of both Insulanebria species have one or more setiferous pores on elytral interval 7 as well as interval 3, whereas among members of the other subgenera, only a few individuals of Nebria (Reductonebria) diversa LeConte, 1863 have any setiferous pores on interval 7. In addition, the intervals bearing setae in Insulanebria members are moderately catenate while they are not or only faintly catenate in members of the other two subgenera except again for some specimens of N. diversa . The median lobe of male genitalia is only faintly deflected right in dorsal aspect in Insulanebria members, more distinctly deflected right in members of the other groups. Females of Insulanebria species have valvifers without vestiture, the longitudinal axis of the bursa only slightly arched basodorsally in lateral aspect, the spermathecal chamber without dorsal or anterodorsal sclerites but with the insemination duct sclerotized as a long, narrow plate ventrally in the chamber, and the spermathecal duct inserted sub-basodorsally on the spermathecal chamber. By contrast, females of the other two subgenera, have valvifers with vestiture, the longitudinal axis of the bursa moderately to markedly sigmoid dorsally in lateral aspect, the spermathecal chamber with either dorsal or anterodorsal sclerites but with the insemination duct not sclerotized in the chamber, and the spermathecal duct inserted basodorsally on the spermathecal chamber.

Known distribution and diversity.

The geographical range of this clade is restricted to the Kamchatka Peninsula and Kuril Islands Archipelago. It includes only two species, N. carbonaria and N. snowi , both of which have previously been included in subgenus Nebria Reductonebria .