Mecodema curvidens ( Broun, 1915 )

Seldon, David S. & Leschen, Richard A. B., 2011, Revision of the Mecodema curvidens species group (Coleoptera: Carabidae: Broscini), Zootaxa 2829, pp. 1-45 : 27-28

Mecodema curvidens ( Broun, 1915) (redescription)

Figures: 5, 6g, 10e, 12c, 16b, 17a, 25.

Metaglymma curvidens Broun, 1915: 273 .

Mecodema exitiosus Brookes, 1926: 441 . New synonomy.

Diagnosis. Head and body broad. Clypeus with a single setose puncture on each side bearing 2 setae. Prothoracic carina narrow, crenulated and extended to beyond anterior angle. Pronotal fovea shallow and narrow. Elytra striae with regularly distributed, small asetose punctures. Setose punctures of 3rd ventrite absent, 4th ventrite may be absent or present and 5th ventrite present. Apical portion of aedeagus symmetrically rounded with a twist to right of vertical axis, absent. Dorso-apical portion of central spicule, greatly expanded. Basal lobe of left paramere rectangular, arm relatively large and apical lobe medium, with setation along apical ¾ of ventral edge.

Description. Length 18–24 mm. Colour black. Head and body broad. Microsculpture of frons and vertex absent. Vertexal groove narrow and defined entire length. Form of microsculpture on anterior area of clypeus, sulcate. Clypeus with a single setose puncture on each side, bearing 2 setae. Form of lobes of mentum, square. Submentum constriction narrow with less than or equal to 6 setae. Prothoracic carina narrow, crenulated and extended beyond anterior angle. Pronotum broad and flattened, posterior lateral sinuation parallel or slightly angled outward, pronotal fovea shallow and narrow, rugose microsculpture may be present laterally on pronotal disc. Elytra broad and flat, striae with regularly distributed small asetose punctures, intervals flat. Setose punctures of mesocoxae present, absent on metacoxae. Setose punctures of 3rd ventrite absent, present on 4th and 5th ventrites. Apical portion of aedeagus symmetrically rounded with a twist to right of vertical axis, absent. Dorso-apical portion of central spicule, greatly expanded. Left paramere basal lobe rectangular, arm relatively large, apical lobe relatively small, with setation along apical ¾ of ventral edge.

Comments. This species was described by Broun (1915) as species no. 3683 and was originally included in the genus Metaglymma Bates. The name was based on a single female specimen from Opotiki. The type specimen is missing the antennomeres 5–11 from the right antenna and the tarsi from the right fore-leg and left mid-leg. The holotype of Mecodema exitiosus in the NZAC was incorrectly identified and wrongly synonymised by Britton (1949) under M. occiputale ; it should instead be synonymised under M. curvidens . At first we thought that M. curvidens and M. atrox were the same species (or geographical variants of M. occiputale ) due to the similarities in external appearance of the three species. However, the differences can be observed in the structures of the aedeagus and although the ranges of these three species do overlap, they are distinct species based on the results of the phylogenetic analyses (fig. 5). As with the northern species of this group, M. curvidens is restricted to relatively intact native forests (although it has been collected in small native forest fragments), most specimens are found in mature forest on the eastern areas of the Kaimai Ranges.

Distribution. North Island: Bay of Plenty (BP), Type locality: Opotiki.

Holotype ( Metaglymma curvidens ): ( BMNH) 3683. [hw] / New Zeal. Broun Coll. Brit. Mus. 1923-482. (red line beneath NZ) / Opotiki. Decr. 1912. [hw] / Metaglymma curvidens . Ψ. [hw] / HOLOTYPE Metaglymma curvidens Broun confirmed by Seldon & Leschen 2010. [red label]

Holotype ( Mecodema exitiosus ): ( NZAC) Okauia 16.1.21 [hw] / Holotype (faded orange label) [hw] / Mecodema exitiosus Brookes [hw] / NZ Arthropod Collection NZAC 04011128.

Other material examined: BP: 3, Okauia 1927 C.E. Clarke ( AMNZ); 1, Okauia 1953 A.E. Brookes ( NZAC); 1, Okauia 1927 A.E. Brookes ( NZAC); 8, Okauia 1921 A.E. Brookes ( NZAC); 1, Okauia 1944 A.E. Brookes ( NZAC); 1, Okauia 1922 A.E. Brookes ( NZAC); BP: 1, Pyes Pa 1921 A.E. Brookes ( NZAC); 1, Pyes Pa Rimu Loop Tk 2005 D.S. Seldon ETOH ( NZAC); 3, Pyes Pa 1921 E. Fairburn ( NZAC); 1, Okuaia 1921 E. Fairburn ( NZAC); 1, Whakamakawa Res. 1969 J.I. Townsend ( NZAC); 1, no label data ( NZAC); 1, Okauia west Kaimai Range 1931 A.E. Brookes ( NZAC).