Mecodema moniliferum Bates 1867, comb. n.
Creators: name: Seldon, David S.
name: Buckley, Thomas R.
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Carabidae
Mecodema
Mecodema moniliferum

description: Mecodema moniliferum Bates, 1867, comb. n.
Figure 39.
Metaglymma monilifer Bates, 1867 (Canterbury).
Metaglymma rugipenne Broun, 1893a (Ashburton, MC), synonymised by Britton 1949.
Metaglymma minor Broun, 1905 (north Canterbury), synonymised by Britton 1949.
Diagnosis: Distinguished from other Mecodema species by having: 1, ventrites 4–5 bearing numerous setose punctures; 2, elytral striae defined anteriorly and laterally by large, irregularly spaced asetose punctures (Fig. 39); 3, shape of basal lobe and setal distribution along ventral edge of left paramere (Fig. 39 LP).
Description: Length 14.6–19.5 mm, pronotal width 4.2–6.2 mm, elytral width 5.1–7.1 mm. Colour of entire body matte reddish-brown to matte black.
Head: Narrow and flat (Fig. 14C). Vertex (Fig. 9) smooth; vertexal groove narrow laterally, indistinct medially; large supraorbital puncture bearing 4–5 setae; 1 shallow supraorbital groove; frons with a small rounded depression each side of midline; frontoclypeal suture a distinctly narrow, straight groove between small tentorial pits; anterior area of clypeus smooth, 1 setose puncture each side bearing 1 seta (Fig. 39). Labrum rounded, anterior edge outwardly curved with 2 proximate central setae, 2 setae each side evenly spaced. Mentum lobes squared (Fig. 12G), mentum process long and broad, slightly angled upward (15°), strongly indentate (Fig. 12A); mentum setae present. Submentum sclerite constriction narrow with 6 setae, large gap medially, evenly distributed laterally. Stipes with 2 basal setae. Gula pits large, suture poorly defined, gula flat with transverse lines. Gena (Fig. 2) with fine wrinkles across entire area.
Prothorax: Prothoracic carina broad the entire length, moderately crenulated with 5–8 setae each side (Fig. 39), extended to anterior angle; posterior lateral sinuation indistinctly carinate, slightly angled inward; pronotum broad and moderately deflected laterally, overall shape rounded; midline indistinctly impressed, posterior medial diamond-shaped impression only, disc with very fine wrinkles laterally (Fig. 39); pronotal foveae broad and shallow; anterior edge slightly inwardly curved, posterior edge curved inwardly medially. Prosternum flat with very fine lines; proepisternum without microsculpture. Procoxal setae (Fig. 2) absent; protibia distally expanded and shovel-like (Fig. 10B).
Elytra: Broad and moderately deflected, length truncated and steeply sloped to apex; humeral angle evenly convex (Fig. 6B); basal margin distinctly curved and bevelled to base, interval 1 extended to margin; lateral carina narrow the entire length, extended to humeral angle; humerus with 4–6 setose punctures within angle (Fig. 39); suture impressed but no more so than striae; striae with small, regularly spaced, asetose punctures, striae 1–4 with obsolescent punctures, increasingly defined laterally (Fig. 39); intervals 1–6 weakly convex, intervals 7–9 moderately convex; interval microsculpture present as transverse lines; 7 th strial setal pattern with 2–3 setose punctures in anterior ½, 5–6 setose punctures in posterior ½, setose punctures small.
Ventral surface: Mesepisternum (Fig. 2) with a few rugose wrinkles; metepisternum without microsculpture; setose punctures present on mesocoxae (1) and metacoxae (2). All abdominal ventrites finely lineate laterally (sparse); ventrite 3 with 1–2 setose punctures each side of midline, ventrite 4 with 3–4 setose punctures each side of midline, ventrite 5 with 6–8 setose punctures each side of midline; ventrite 6 setae present: ♂ with 2 setose punctures at junction of straight apical edge and curve anterad, ♀ with 2 setose punctures, distantly spaced at junction of bluntly rounded apical edge and curve anterad; ventrites foveate laterally. Anterior metaventrite process (Fig. 2) a long narrow triangle without a carina.
Male genitalia: Apical portion of penis lobe asymmetrically rounded with a distinct deflection to right of vertical axis (VV) (Fig. 15A), apex curve flat and slightly forward of vertical axis (Fig. 39 PL); shaft of penis lobe broad and short with curve of ventral edge to left (VV); overall length of penis lobe without curve ventrally (straight). 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 short and narrow; setal (scales) coverage of the apical plate sparse (1–25%); size of left setose flange small; size of right setose flange large. Left paramere basal lobe ovate, dorsal hump absent with short slope to arm; arm long and narrow; terminal lobe not defined, apical tuft of long setae (Fig. 39 LP); very short setae along arm ventral edge, long setae along basal lobe ventral edge; ventral edge slightly curved, setae along entire length. Right paramere long and narrowly rectangular, slightly narrowed to apex, setae extended along apical ¾ of ventral edge (Fig. 39 RP).
Female genitalia: Basal gonocoxite 1 short and broad, ventral surface with a few rugose wrinkles; internal dorso-lateral carina with 2 setae. Gonocoxite 2 short and broad, ovate in shape; 1 short seta at base near junction with gonocoxite 1 (ventral surface). Ramus (Fig. 5) long and broad.
Comments: Although Mecodema moniliferum is only found in the braided river systems of the South Island, analyses show that it nested within the monophyletic curvidens species group.
Distribution: New Zealand, South Island, Kaikoura (KA), north to south Canterbury (MC, NC, SC).
Holotype: not viewed. Type in the R. Oberthür Collection at Rennes, Muséum of National d’Histoire Naturelle, France. Type locality near Christchurch; collected by Mr Fereday (Britton, 1949).
Material examined: 1♀, Moyunau I. 1–5.xii.67 / Pit traps A. Whittaker / Metaglymma monilifer Bates Det. J.I. Townsend 18.I.68 [hw] (NZAC); 2, Waikuku Beach, Rangiora, 2 Dec 1941, D. Spiller [hw] (NZAC); 1♂, 1♀ [card mounted], Mt Algidus, 2000’, 2– 13.12.59, J.I.Townsend (NZAC).
description: Published as part of Seldon, David S. & Buckley, Thomas R., 2019, The genus Mecodema Blanchard 1853 (Coleoptera: Carabidae: Broscini) from the North Island, New Zealand, pp. 1-148 in Zootaxa 4598 (1) on pages 74-76, DOI: 10.11646/zootaxa.4598.1.1, http://zenodo.org/record/2668063