Mecodema aoteanoho Seldon & Leschen, 2011 .

Figure 18.

Diagnosis: Distinguished from other North Island Mecodema species by: 1, the prothoracic carina with 4–5 setae along each side ( curvidens species group); 2, elytral striae and intervals abruptly truncated at basal margin; 3, 7 th stria with 4 long setae, evenly distributed in posterior ½; 4, interval 8 truncated basally by humeral puncture, forming distinctive angle with interval 7.

Description: Length 19–24 mm, pronotal width 4.5–6 mm, elytral width 5.5–7 mm. Colour of entire body matte black, coxae and legs glossy black.

Head: Broad and convex (Fig. 14B). Vertex smooth; vertexal groove narrow and well-defined the entire length; small supraorbital puncture bearing 3 setae; a single narrow and large supraorbital groove anterad eye; frons with a broad and shallow depression each side of midline; frontoclypeal suture shallow but defined between very small tentorial pits; anterior area of clypeus with narrowly grooved; clypeus with 1 setose puncture on each side bearing 2–3 setae. Labrum rectangular, anterior edge straight with 2 proximate central setae, 2 setae each side evenly spaced. Mentum lobes squared (Fig. 12G), median process narrow and short, upward angle absent, indentation notched (Fig. 12D); setose punctures present. Submentum sclerite constriction narrow with 6 very long, evenly spaced setae. Stipes with 2 basal setae. Gula pits small, suture indistinct, gula flat with a very fine isodiametric pattern. Gena with very fine transverse wrinkles (may be absent).

Prothorax: Prothoracic carina narrow the entire length, slightly crenulated with 4–5 setae each side (Fig. 18), extended beyond anterior angle; posterior lateral sinuation indistinctly carinate, slightly angled inward; pronotum broad but moderately deflected laterally, overall shape squared (sides straight) (Fig 18); midline defined in anterior half only, medial impressions absent, disc with transverse wrinkles laterally (may be absent); pronotal fovea (Fig. 11) shallow and narrow; anterior edge slightly inwardly curved, posterior edge straight (Fig. 18). Prosternum weakly convex and smooth; proepisternum (Fig. 2) without microsculpture. Procoxal setae absent; protibia distally expanded and shovel-like (Fig. 10B).

Elytra: Narrow and laterally deflected; humeral angle anteriorly convergent (Fig. 6A); basal margin very slightly curved and steeply bevelled to base (striae and all intervals abruptly truncated at margin); lateral carina very narrow the entire length, extended to humeral angle; humerus with 2 large setose punctures near humeral angle (Fig. 18); suture impressed, but not more so than striae; striae with regularly distributed, small, asetose punctures that increase slightly in size laterally; intervals 1–4 flat to weakly convex, convexity increased laterally; interval microsculpture absent; interval 8 truncated basally by humeral puncture, forming distinct angle with interval 7 (Fig. 18); 7 th strial setal pattern with 4 long setae evenly spaced in posterior ½ (only in apical region), setose punctures small.

Ventral surface: Mesepisternum and metepisternum without microsculpture; setose punctures of mesocoxae and metacoxae absent. Abdominal ventrites 1–5 smooth; ventrite 6 setae present: ♂ with 1 setose puncture each side located of straight apical edge and curve anterad, ♀ with 2 evenly spaced setose punctures each side of midline along a bluntly rounded apical edge; lateral foveae absent. Anterior metaventrite process a triangle with a very broad carina, especially between metacoxae.

Male genitalia: Apical portion of penis lobe symmetrically rounded with a moderate deflection to right of vertical axis (VV) (Fig. 15B); shaft of penis lobe straight and narrow (VV) (Fig. 18 PL), overall length of penis lobe slightly curved ventrally (LV) (Fig. 16A). Structures of the endophallus (Fig. 4): lateral form of the apex of the central spicule rounded; dorsal form of the apex of the central spicule is narrow and short; setal (scales) coverage of the apical plate sparse (1–25%); left setose flange small; right setose flange large. Left paramere main body rectangular, slightly humped dorsally forming a gently sloped anterior angle (15°), angle very short and continued to form arm; arm broad and short (<half main body length); terminal lobe relatively small, apical tuft of long setae, with setation continuing along apical ½ of ventral edge (Fig. 18 LP); ventral edge of main body straight. Right paramere only slightly smaller than left paramere, narrowly rectangular, arm relatively long (½ of length), setae extended along apical ¾ length of ventral edge with longer setae behind apical lobe (Fig. 18 RP).

Female genitalia: Basal gonocoxite 1 short and broad, ventral surface entirely wrinkled, dorsal surface with a light scattering of sensillar pits; internal dorso-lateral carina with a single short apical seta. Gonocoxite 2 (Fig. 5) paddle-like, bluntly rounded, ventral surface slightly convex with scattered sensilli, raised carina around edge. Ramus long and narrow, but broadened apically.

Comments: Mecodema aoteanoho is the first described carabid species that is endemic to Aotea (Great Barrier Island). It is the sister taxon M. haunoho (Te Hauturu-o-Toi/Little Barrier Island).

Distribution: New Zealand, North Island, Great Barrier Island (only).

Holotype: NZAC male labelled. NEW ZEALAND CL Great Barrier I 23–28 Mar 1978 ESNZ Field Trip / Whangaparapara Track x under logs [hw] / HOLOTYPE Mecodema aoteanoho n. sp. design. Seldon & Leschen 2011 [red label].

Paratypes: (see Seldon & Leschen 2011).