Ctenognathus edwardsii ( Bates, 1874 )

Larochelle & Larivière, Marie-Claude, 2021, Synopsis of the tribe Platynini in New Zealand (Coleoptera: Carabidae), Insecta Mundi 2021 (864), pp. 1-96 : 47-48

Ctenognathus edwardsii ( Bates, 1874)

Fig. 68 , 111 , 130

Platynus Edwardsii Bates, 1874: 239 (redescribed in 1875: 302). Holotype: “ New Zealand ” (could not be located either in MNHN or in CMNZ).

Anchomenus (Platynus) edwardsii: Broun 1880: 26 .

Anchomenus macrocoelis Broun, 1908: 346 . Lectotype (here designated): male (BMNH) labeled “Type (circular red-bordered label; typed) / 2664. [male symbol] (hand-written) / [MK] Hermitage. Mt. Cook. (hand-written) / New Zealand. Broun. Coll. Brit. Mus. 1922–482 (white label with red horizontal line; typed) / Anchomenus macrocoelis . (hand-written) / LECTOTYPE [male symbol] Anchomenus macrocoelis Broun, 1908 designated by Larochelle & Larivière, 2021 (red label; typed).” New synonym

Anchomenus edwardsii: Hudson 1923: 356 .

Agonum (Platynus) edwardsii: Csiki 1931: 853 .

Agonum (Anchomenus) macrocoele: Csiki 1931: 865 .

Anchomenus edwardsii: Hudson 1934: 174 .

Anchomenus macrocaelis [sic]: Hudson 1934: 174.

Ctenognathus edwardsii: Larochelle and Larivière 2007: 81 , 111.

Ctenognathus macrocoelis: Larochelle and Larivière 2007: 81 , 111.

Description. Body length 10.4–12.6 mm. Head, pronotum, elytra, and abdomen black; antennae and palpi dark rufous; legs piceous black (tarsi with reddish tinge). Microsculpture isodiametric on head, pronotum, and elytra (elytra almost granulate). Iridescence absent. Head and pronotum very shiny, elytra dull. Forebody moderately wide in comparison to elytra. Head. Moderately wide. Mandibles moderately long and curved anteriorly. Labrum strongly transverse, moderately emarginate anteriorly. Eyes strongly convex; two setiferous punctures on inner side of each eye. Tempora not inflated. Neck constriction absent dorsolaterally. Mentum: medial tooth slightly or moderately emarginate apically; two setae. Submentum with six setae. Palpi with terminal segment obtuse apically. Thorax. Pronotum slightly convex, impunctate, obsoletely wrinkled on disc, deeply wrinkled across base, wide, subquadrate, widest before middle; apex strongly emarginate; anterolateral angles well developed, broadly rounded; anterior bead incomplete, obsolete medially; sides moderately rounded, slightly sinuate posteriorly; lateral beads complete; lateral depressions narrow anteriorly, widened posteriorly; two setiferous punctures (anterior and posterior) on each side; posterolateral angles rectangular; laterobasal foveae moderately deep, very wide, meeting toward pronotal midline, prolonged forward; posterior bead obsolete; base subtruncate. Legs. Moderately long. Metafemora with two posteroventral setae. Meso- and metatarsomeres 1–4 well developed, tricarinate dorsally, deeply bisulcate laterally. Metatarsomeres 4 moderately bilobed, symmetrical apically. Metatarsomeres 5 glabrous ventrally. Elytra. Subdepressed, not sloping down toward apex, oblong, widest behind middle. Shoulders moderately rounded. Sides moderately rounded. Scutellar setiferous pore visible. Scutellar striole moderately long, impunctate. Striae shallow, impunctate. Intervals subdepressed; interval 3 with three shallow, minute setiferous punctures. Umbilicate series with 17–19 setiferous punctures. Subapical sinuations strong. Apices rounded. Abdomen. Sterna IV–VI: both sexes with two long apical ambulatory setae. Sternum VII (last visible sternum): male with four long apical ambulatory setae; female with eight or ten long apical ambulatory setae. Aedeagus. Lateral view ( Fig. 111 ): strongly arcuate; base slightly convex dorsally, with marginal blade instead of basal lobe; middle slightly convex, almost straight in basal half and strongly convex in apical half dorsally, strongly concave ventrally, with dorsal membranous area very wide in apical half and moderately long; apex slender, slightly convex dorsally, slightly concave ventrally, with extreme tip narrow and very long. Dorsal view: very wide, asymmetrical (ostium of membranous area deflected to the left); basal bulb moderately distant from membranous area.

Material examined. 192 specimens ( AMNZ, BMNH, JNNZ, LUNZ, MONZ, NZAC).

Geographic distribution ( Fig. 130 ). South Island: CO, FD, MC, MK (mostly), OL, SC, SL. Stewart Island.

Ecology. Lowland, montane, subalpine. Epigean. Dry forests (beech). Shaded ground; dry soil. Nocturnal; hides during the day under logs and stones. Gregarious.

Biology. Seasonality: October–February, April–May. Tenerals: November, January–March, May. Predacious (based on mouthpart morphology). Occasionally infested with mites.

Dispersal power. Subapterous (incapable of flight). Moderate runner. Occasional climber (on trees).

Collecting techniques. Turning logs and stones; pitfall trapping.

References. Larochelle and Larivière 2001: 130–131 (as “ Anchomenus ” edwardsii , “ A.” macrocoelis ; catalogue; biology, dispersal power, ecology, geographic distribution, references), 2007: 81, 111 (as Ctenognathus edwardsii , C. macrocoelis ; list), 2016: 36 (as Ctenognathus edwardsii , C. macrocoelis ; list).

Remarks. The holotype of Platynus edwardsii could not be located either in MNHN or in CMNZ where Bates’ specimens can usually be found. However, there is no ambiguity regarding the identity of this taxon; the original description can only apply to the species as currently understood. In addition to diagnostic characters of the male genitalia, Ctenognathus edwardsii has the following distinguishing features: pronotum wrinkled on disc and across base, subquadrate, laterobasal foveae of pronotum very wide, meeting toward pronotal midline; elytra dull, subdepressed, interval 3 with three shallow, minute setiferous punctures.

Broun described Anchomenus macrocoelis from two specimens, one of which (a male) was located (BMNH) and is here designated as a lectotype in order to preserve stability of nomenclature in the future. The morphology of this lectotype corresponds to Bates’ original description of Platynus edwardsii . The two taxa are therefore conspecific.

Figures

Figures 65–68. Dorsal habitus. 65) Ctenognathus takahe new species. 66) C. arnaudensis. 67) C. marieclaudiae new species. 68) C. edwardsii. Scale line = 1 mm.

Figures 108–114. Aedeagus, lateral. 108) Ctenognathus takahe new species. 109) C. arnaudensis. 110) C. marieclaudiae new species. 111) C. edwardsii. 112) C. kaikoura new species. 113) C. sandageri. 114) C. helmsi.

Figures 130–135. Species distribution maps. 130) Ctenognathus edwardsii. 131) C. elevatus. 132) C. garnerae new species. 133) C. helmsi. 134) C. hoarei new species. 135) C. intermedius.