Mecodema sulcatum (Sharp, 1886) (redescription)

Figures: 5, 11a, 20c, 25.

Metaglymma sulcatum Sharp, 1886: 361.

Metaglymma modicum Broun, 1894: 305. Synonymised by Britton, 1949: 578. Metaglymma doullii Broun, 1905: 543. Synonymised by Britton, 1949: 578. Metaglymma ovicolle Broun, 1914b: 147. Synonymised by Britton, 1949: 578. Mecodema sulcatum (Sharp, 1886). Combination by Britton, 1949: 578.

Diagnosis. Head and body highly convex. Clypeus with a single setose puncture on each side, bearing 1 seta. Prothoracic carina narrow, crenulation absent and extended to beyond anterior angle. Pronotal fovea shallow and narrow. Elytral striae with regularly distributed, small asetose punctures. Setose punctures on 3rd, 4th and 5th ventrites absent. Apical portion of aedeagus symmetrically rounded with twist to right of vertical axis absent. Dorso-apical portion of central spicule, not greatly expanded. Basal lobe of left paramere rectangular, arm and apical lobe relatively small, and with setation sparsely distributed along ventral edge.

Description. Length 11–18 mm. Colour black. Head and body highly convex. Microsculpture of frons and vertex absent. Vertexal groove narrow, defined medially but laterally shallow. Form of microsculpture on anterior area of clypeus, poorly defined. Clypeus with a single setose puncture on each side, bearing 1 seta. Form of lobes of the mentum, square. Submentum constriction narrow, with greater than or equal to 6 setae. Prothoracic carina narrow, crenulation absent and extended to beyond anterior angle. Pronotum highly convex, posterior lateral sinuation highly angled inward. Pronotal fovea shallow and narrow, rugose microsculpture may be present laterally on pronotal disc. Elytra highly convex, striae with small regularly distributed asetose punctures, intervals slightly convex. One to three setose punctures present on mesocoxa, one setose puncture present on metacoxa. Setose punctures on 3rd, 4th and 5th ventrites absent. Apical portion of aedeagus symmetrically rounded with twist to right of vertical axis absent. Dorso-apical portion of central spicule, not greatly expanded. Left paramere basal lobe rectangular, arm and apical lobe relatively small, and with setation sparsely distributed along ventral edge.

Comments. This species was described by Sharp (1886) and was placed in the genus Metaglymma. Sharp (1886) mentioned that he had three specimens in bad condition for the description of M. sulcatum, but we have only located two from the British Museum, and one of these was clearly labelled as the type by Sharp. It is missing antennomeres 5–11 from the right antenna while the second specimen is completely intact. Because we did not locate a third specimen, suggesting a split series that may have “ type ” written on a label of a third specimen we have designated the following specimens as Lectotype and Paralectotype. The synonymies (Metaglymma modicum, M. doullii and M. ovicolle) and present combination (Mecodema sulcatum) were provided by Britton (1949). M. sulcatum has the same geographical range of M. oblongum from the Hawke’s Bay to the northern region of the South Island, and are extremely difficult to separate using external morphology. However, M. sulcatum is the sister species of M. oregoides and both can be differentiated from M. oblongum by genitalic characters.

Distribution. North Island: Hawke’s Bay (HB), Wairarapa (WA), Wellington (WN); South Island: Kaikoura (KA), Malborough (MB), North Canterbury (NC), Nelson (NN), Malborough Sounds (SD). Type Locality: Picton, SD, South Island.

Lectotype: (BMNH) card mounted Metaglymma sulcatum Type D. S. Picton N. Zeald. / SYN-TYPE (round label with blue border) / Type H. T. (round label with red border) / Picton New Zealand. Helms. / Sharp Coll. 1905- 313. / LECTOTYPE Metaglymma sulcatum Sharp design. by Seldon & Leschen 2010 [red label].

Paralectotype: (BMNH) card mounted Metaglymma sulcatum D. S. Picton N. Zeald. / I 4 [hw] / Picton New Zealand. Helms. / Sharp Coll. 1905-313. / SYN-TYPE (round label with blue border) / PARALECTOTYPE Metaglymma sulcatum Sharp design. by Seldon & Leschen 2010 [red label].

Holotype (Metaglymma doullii): (BMNH) Type (round label with red border) / 2611 3 [hw] / New Zealand. (red line underneath) Broun Coll. Brit. Mus. 1922-482. / A. Doull N. Canterbury [hw] / Metaglymma doullii [hw].

Holotype (Metaglymma modicum): (BMNH) Type (round label with red border) / 2607 3 [hw] / New Zealand. (red line underneath) Broun Coll. Brit. Mus. 1922-482 / Wellington / Metaglymma modicum [hw].

Holotype (Metaglymma ovicolle): (BMNH) Type (round label with red border) / 3506. [hw] / New Zealand. (red line underneath) Broun Coll. Brit. Mus. 1922-482. / Otaraia April 1911. [hw] / Metaglymma ovicolle [hw].

Other material examined: HB: 10, Bare Is. 1992 G. Wallis (NZAC); 4, Kereru Rd year unknown J. Grindell (NZAC); WN: 10, Mana Is. 1993 J.I. Townsend (NZAC); 1, Stephens Is. Cook Straight 1930 G. V. Hudson (specimen identified by Britton, BMNH) KA: 1, Oaro Kaikoura 1968 J.C. Watt (NZAC); 1, Nth Canterbury 1977 J.I. Townsend (NZAC); 1, Kaikoura town, 1961, P.M. Johns (LUNZ); 1, Oaro S. of Kaikoura 1946 C. E. Clarke (BMNH); 7, Oaro Kaikoura 1947 C. E. Clarke (BMNH); Additional material viewed from MONZ.