Agnosthaetus imitator Clarke, 2011

Clarke, Dave J., 2011, A Revision of the New Zealand Endemic Rove Beetle Genus Agnosthaetus Bernhauer (Coleoptera: Staphylinidae), The Coleopterists Bulletin (mo 10) 2011, pp. 1-118 : 49-50

(19) Agnosthaetus imitator Clarke , new species

( Figs. 143 , 148 , 152 , Map 5 )

Type Material. Holotype. ♂, with four labels:

“ New Zealand WN| Akatarawa Sdle [Saddle:

40°57′S 175°6.5′E]| Tararua FP Tk | 6km from SH| 17 Jan 1984 / H.P. McColl | Litter | Nothofagus | menziesii / FMNH-INS 0000 038 341 / HOLOTYPE Agnosthaetus imitator Clarke , ♂, design. D. Clarke 2011/ Permount ”, in NZAC. Aedeagus mounted on clear strip in Permount. Paratypes. 11 specimens (3♂ 7♀ 1 unsexed). NEW ZEALAND: North Island: WN: Akatarawa Saddle, Tararua F.P. Trk, 6 km from SH , 40°57.06′S, 175°6.54′E [coord.= Akatarawa Saddle], 17.i.1984, Nothofagus menziessi litter, H.P. McColl, 1♀, FMNH-INS 38342 (in NZAC); Tararua Forest Park, Judd Ridge , Field’ s Track, Field Hut vic., 855 m, ANMT 1153 , 40°54.474′S, 175°15.371′E, broadleaf ( Nothofagus menziesii - Weinmannia racemosa -podocarp forest, 24–26.xi.2005, FMHD#2005-039, berl., forest leaf litter (mostly Nothofagus ), A. Solodovnikov & D. Clarke, 1♂, 2♀ (in FMNH); 24–26.xi.2005, FMHD#2005-040, berl., moss on logs, A. Solodovnikov & D. Clarke, 2♀ (in FMNH); 24.xi.2005, FMHD#2005-037, berl., sedge-base litter, A. Solodovnikov & D. Clarke, 1♂ (in FMNH); Tararua Forest Park , Southern Crossing btwn. Kime Hut & Dennan Peak, 1200–1300 m, ANMT 1154 , 40°56′S, 175°16′E, alpine zone with scrub Olearia , 25.xi.2005, FMHD#2005-038, berl., mixed litter under shrubs, A. Solodovnikov & D. Clarke, 1♂ (in FMNH); Tararua Ra. , Judd Ridge, Otaki Forks, 800 m , 40°52.2′S, 175°13.56′E [coord.= Otaki Forks], 5.xi.1980, 80/101, litter, C.F. Butcher, 2♀, 1 sex unknown, FMNH-INS 38343– 344, 345 (in NZAC) .

Diagnosis. Agnosthaetus imitator can be distinguished from all other species of Agnosthaetus by the combination of the normal semi-circular eye (similar to Figs. 57–60 ), narrow dorsal tentorial sulcus, distinct tooth at base of mentum (similar to Fig. 66 , arrow), metathoracic pleural ridge ( Fig. 24 , mp), and lack of microsculpture on the head and thorax. The aedeagus may be distinguished from those of the similar species A. orongo and A. aorangi by the distinctly convex sides of the apical part of the median lobe and the elongate apical lobe of the paramere, together with the four minute setae on the inner parameral face ( Fig. 148 , cf. Figs. 149–150 ).

Description. Color: Color variably yellowish to reddish brown, abdomen occasionally more darkly pigmented posteriorly. Head: Frontal ridge absent, or present (cf. Fig. 12 , fr). Dorsum sparsely punctate; with punctures distributed anteriorly, laterally, and posteriorly on disc, middle part impunctate. Punctures shallow, rather indistinct; diameter subequal to or less than diameter of eye facet; interpuncture distance approximately equal to or greater than puncture diameter, less posterolaterally. Dorsal microsculpture absent, or present only anterior to dorsal tentorial sulci; very faintly reticulate. Dorsal tentorial sulcus (cf. Figs. 10–11 , dt) broadly ovate; width twice puncture diameter. Sublongitudinal ridge (cf. Fig. 10 , sr) distinct; not confused by smaller carinae or punctures; crest at antennal tubercle without distinct microsculpture. Area above and behind antenno-ocular carina ( Figs. 10–11 , arrow) usually without, or else only indistinct, subsidiary carinae. Antenno-ocular carina joining eye at about middle. Temple ( Fig. 11 , tm) short, less than 50% EYL. Subocular surface more or less evenly microsculptured (cf. Fig. 65 ). Labrum not distinctly sexually dimorphic ( Fig. 143 ). Apical labral margin in males moderately broadly and shallowly emarginate medially, evenly dentate, with 16–26 teeth (n =4), all teeth normal, projecting more or less anteriorly. Apical labral margin in females broadly rounded, subtruncate to slightly concave medially; with 19– 22 teeth (n =6), all teeth subequal in length. Adoral labral surface in males smooth, without subapical transverse ridge. Mandible sexually dimorphic; males with single, dorsally directed tooth, without preapical spur (cf. Fig. 189 ); females with single, mesially projecting tooth, without spur. Mentum with distinct basomedian tooth (cf. Figs. 65–66 ). Prothorax: Pronotum without microsculpture. Medial pronotal sulci anteriorly separate from and terminating posterior to anterior punctures or continuous with anterior punctures (cf. Fig. 76 ). Distance between medial sulci subequal along entire length. Pronotal basolateral carina present, but only weakly developed. Anterior pronotal puncture (cf. Fig. 70 , ap) indistinct; medial puncture (cf. Fig. 70 , mu) distinct; basal puncture ( Fig. 70 , bu) absent or indistinct. Medial pronotal seta subequidistant from medial and lateral sulci (cf. Figs. 75–76 ). Pronotal hypomeron ( Fig. 24 , hy) shiny, without microsculpture. Prosternum without microsculpture, or with faintly reticulate microsculpture. Pterothorax: Elytron ( Fig. 23 , e) without microsculpture; with 2 macrosetae, not set in punctures; laterally with single ridge (cf. Fig. 24 , ek). Mesothoracic epimeral region ( Fig. 24 , mer) shiny, without microsculpture. Metathoracic pleural region ( Fig. 24 , m) shiny, without microsculpture. Metathoracic pleural ridge present, fully developed; metathoracic pleural groove ( Fig. 24 , gr) incomplete posteriorly, forming elongate oval punctiform impression. Abdomen: Abdominal vestiture long, dorsally more or less evenly projecting posteriorly but with middle setae directed posteromedially. Abdominal sternite III of male glabrous apicomedially; IV with distinct broad impression apicomedially, flanked by small dense patches of coarse acuminate setae, with apex broadly sinuous; V with distinct broad impression apicomedially, larger than that on sternite IV, flanked by dense patches of acuminate setae, larger than those on sternite IV, distinctly sinuous apically; VI glabrous and broadly impressed medially; VII with surface nearly glabrous apicomedially. Aedeagus ( Fig. 148 ): “ Type B” (see description on g. 8). Median lobe with apical part delimited ventrally from basal part ( Fig. 148 , arrow). Apical part of median lobe with sides weakly convex, abruptly concavely produced to narrowly acute, sharp point. Apicolateral setae small; apicomedial setae up to 10X longer than apicolateral setae ( Fig. 152 ). Paramere exceeding apex of median lobe; in lateral view produced apically into lobe; with apical part perpendicular to median lobe; in dorsal view with outer side gently convex; with cluster of 4 minute setae on mesal side of apex.

Etymology. The specific epithet imitator is a noun in apposition from the Latin imitator , a mimic, referring to its overall resemblance to orongo .

Distribution. ( Map 5 ). North Island: WN.

Biology and Ecology. Habitat: broadleaf- Nothofagus zone; alpine Olearia scrub. Specimens have been taken from a variety of litter types and moss. Phenology: January; November. Elevation: 800–1,250 m.

Remarks. This species is externally indistinguishable from A. orongo , save for the narrower dorsal sulci, which is not a discrete enough difference to be useful for identification. Males can be distinguished by their secondary sexual characters (more developed in the latter species) and the aedeagal characters mentioned in the diagnosis. From A. aorangi , it may be distinguished by having a distinct and easily seen mental tooth (as in Fig. 66 , arrow; this structure is only weakly developed in A. aorangi and difficult to discern with light microscopy), and males may be distinguished from A. aorangi by the lack of the fin-like teeth on the subapical surface of the labrum, differences in abdominal secondary sexual characters, and aedeagal characters mentioned in the diagnosis.

Figures

Map 5. Geographic distribution of all georeferenced specimens of North Island species in the Agnosthaetus imitator species-group. Triangles = A. imitator; stars = A. aorangi; circles = A. lanceolatus; squares = A. stilbus; X = A. minutus.

Figs. 143–147. Male (left) and female (right) labra of species in the Agnosthaetus imitator species-group, dorsal (anterior margin) view. 143) A. imitator; 144) A. aorangi, female; 145) A. orongo; 146) A. stilbus; 147) A. lanceolatus. Scale bar = 100 mm.

Figs. 148–151. Aedeagi of species in the Agnosthaetus imitator species-group, dorsal (left) and right lateral (right) views. 148) A. imitator; 149) A. aorangi; 150) A. orongo; 151) A. stilbus. Scale bar = 100 mm.

Figs. 152–155. Apex of median lobe of species in the Agnosthaetus imitator species-group, ventral view.

Figs. 57–62. Heads of Agnosthaetus spp., dorsal view. 57) A. vicinus; 58) A. heteromastax; 59) A. nitidus;

Figs. 63–68. Heads of Agnosthaetus spp., ventral view. 63) A. brouni; 64) A. stilbus, oblique view; 65) A. chiasma;

Figs. 23–24. Agnosthaetus cariniceps, thorax. 23) Dorsal view; 24) Left lateral view. Scale bars = 100 mm.

Figs. 10–13. Head capsules of Agnosthaetus spp. 10) A. stilbus; 11) A. rodmani; 12) A. brouni; 13) A. chiasma. Scale bars = 100 mm.

Figs. 189–194. Mandibles of Agnosthaetus spp., dorsal view (189–193, left; 194, right). 189) A. newtoni; 190) A. falx; 191) A. stenomastax; 192) A. heteromastax (Rakeahua Valley); 193) A. heteromastax (Big South Cape Island); 194) A. heteromastax (Twilight Bay). Scale bar = 100 mm.

Figs. 75–78. Pronota of Agnosthaetus spp. 75) A. vicinus; 76) A. stilbus; 77) A. nitidus; 78) A. brouni. Scale bar =

Figs. 69–74. Pronota of Agnosthaetus spp. 69) A. chiasma; 70) A. rodmani; 71) A. heteromastax; 72) A. stenomastax;