Mecyclothorax kuiki, Liebherr, James K., 2015

Liebherr, James K., 2015, The Mecyclothorax beetles (Coleoptera, Carabidae, Moriomorphini) of Haleakala-, Maui: Keystone of a hyperdiverse Hawaiian radiation, ZooKeys 544, pp. 1-407 : 235-237

Taxon classification Animalia Coleoptera Carabidae

(096) Mecyclothorax kuiki sp. n. Figs 117F, 118F, 121, 122 D–E, 125

Diagnosis.

This fourth species of the Mecyclothorax vitreus group complex can be diagnosed by the pronotal median base with large punctures traversing the midline of the base, and small longitudinal wrinkles dissecting or at least disturbing the basal margin (Fig. 122 D–E). The median base also has well-developed isodiametric microsculpture between the punctures. The elytra are ellipsoid, the base narrow with the margins laterad the humeri barely extended, resulting in high ratios of MEW/HuW = 2.30-2.39 that are mirrored in Mecyclothorax kipahulu (Fig. 122A) and Mecyclothorax kipwilli (Fig. 115 D–E), but greater than those derived from Mecyclothorax kaumakani (Fig. 122 B–C). The male aedeagal median lobe is of the most plesiomorphic configuration within this species complex, as the median lobe is gracile and moderately curved, and apex is narrowly extended beyond the ostial opening, the tip narrowly rounded and slightly downturned (Fig. 125 A–C, F–G). The male aedeagal internal sac corroborates the median lobe’s relative plesiomorphy, as it is unilobate, long, and generally of the configuration observed across the genus (Fig. 125B, F, G). Setal formula 2 1 2 0. Standardized body length 4.4-5.5 mm.

Description

(n = 5). [The above description of Mecyclothorax kipwilli can serve to describe this species with the following substitutions.] Eyes of similar convexity to Mecyclothorax kipwilli ; ocular ratio = 1.46-1.58, ocular lobe ratio = 0.76-0.81. Pronotum appearing elongate but slightly transverse, MPW/PL = 1.10-1.15, variably constricted basally, MPW/BPW = 1.46-1.65; median base bearing 10-13 isolated punctures across midlength of base, plus fine longitudinal wrinkles along the basal margin. Metathoracic flight wing an ellipsoid strap 1.4 × long as broad, remnant R + M veins present; strap not reaching hind margin of metanotum. Microsculpture of elytral disc shallow, evident, comprising a transversely stretched isodiametric mesh arranged in transverse rows, elytral apex with evident isodiametric mesh. Coloration of vertex rufous with piceous cast; pronotal disc rufobrunneous with piceous cast, margins narrowly paler, rufous; elytral disc rufobrunneous, sutural interval rufous basally and apically, concolorous on disc.

Male genitalia (n = 11). Aedeagal median lobe robust, dorsal surface broadly convex, distance from parameral articulation to tip 2.3 × depth at midlength (Fig. 125 A–C, E–G); apex very narrowly extended, the tip obliquely rounded with dorsoapical face slightly flattened; median lobe sinuously curved in ventral view, right margin slightly concave, left margin briefly convex before narrow, bluntly rounded tip (Fig. 125D); internal sac very broad, cylindrical (Fig. 125B, F–G), length variable, from 1.0 –1.2× parameral articulation-tip distance; a small basal lobe may (Fig. 125B) or may not (Fig. 125 F, G) be present on dorsal surface of sac; ventral sac surface covered with shaggy pelage of longer microtrichia; flagellar plate robust, very large, length 0.61 –0.67× parameral articulation-tip distance (plate size is positively associated with sac length, Fig. 125B, F–G).

Female reproductive tract (n = 1). Bursa copulatrix columnar, broad and elongate, length 1.48 mm, breadth 0.57 mm (Fig. 117F); bursal walls translucent, surface more thickly wrinkled near base, apex with only thin wrinkles; gonocoxite 1 with 3-4 apical fringe setae and 6-9 smaller setae along medial surface (Fig. 118F); gonocoxite 2 falcate, apex subacuminate, basal extension elongate with curved terminus, 2 thin lateral ensiform setae, apical nematiform setae on medioventral surface at 0.71 × gonocoxite length.

Holotype.

Male (CUIC) dissected and labeled: HI: Maui Haleakala N.P. / Kipahulu west rim below / Kuiki sift humus ex ohia / 14-V-1993 lot 02 / el. 2090 m // J.K. Liebherr & / A.C. Medeiros / Collectors // Mecyclothorax kuiki ♂ #80 // HOLOTYPE / Mecyclothorax / kuiki / Liebherr / det. J.K. Liebherr 2015 (black-margined red label).

Paratypes.

84 specimens (see Appendix).

Etymology.

As most specimens of this species have been found in proximity to Kuiki, the summit of Kīpahulu Valley’s west rim, that locality name is used as the epithet for this final species in the Mecyclothorax kipwilli + Mecyclothorax kipahulu + Mecyclothorax kaumakani + Mecyclothorax kuiki species quartet.

Distribution and habitat.

Analogous to the distribution of Mecyclothorax kaumakani , Mecyclothorax kuiki is disjunctly distributed north and south of Kīpahulu Valley (Fig. 121). In the Hāna Bogs region it is known only from New Greensword Bog, 1850 m elevation, whereas various Manawainui Planeze localities range 1525-2145 m elevation. Records are primarily associated with ‘ōhi‘a, with one collecting event associated with Leptecophylla (pūkiawe).