Mecyclothorax haleakalae (Sharp)

Liebherr, James K., 2015, The Mecyclothorax beetles (Coleoptera, Carabidae, Moriomorphini) of Haleakala-, Maui: Keystone of a hyperdiverse Hawaiian radiation, ZooKeys 544, pp. 1-407 : 216-217

Taxon classification Animalia Coleoptera Carabidae

(089) Mecyclothorax haleakalae (Sharp) Figs 104E, 105E, 110B, 112, 113 A–D, 114

Metrothorax haleakalae Sharp 1903: 271; Swezey 1954: 8 ( koa association).

Mecyclothorax haleakalae , Britton 1948b: 125.

Diagnosis.

This species (Fig. 110B) and Mecyclothorax simpulum (Fig. 110C) both are characterized by a glabrous quadrate pronotum-MPW/PL = 1.07-1.14 for this species-with a densely punctate median base. Specimens of Mecyclothorax haleakalae can be told by the well-developed and regular isodiametric mesh covering the elytral disc. The anterior supraorbital seta is absent from specimens of this species, whereas nearly all specimens examined of Mecyclothorax simpulum have both anterior and posterior pairs of these setae. The male aedeagal median lobe apex is broader dorsoventrally and flattened apically in Mecyclothorax haleakalae males (Figs 113A, C–D), and the internal sac bears two small ventral ostial microtrichial patches (Fig. 113C) which are absent from Mecyclothorax simpulum males (Fig. 113G). Setal formula 1 0 2 0. Standardized body length 5.2-6.0 mm.

Identification

(n = 5). The eyes are convex and large, ocular ratio = 1.51-1.61, ocular lobe ratio = 0.84-0.91. The pronotum is constricted basally, MPW/BPW = 1.56-1.70, with the lateral margin subparallel for 0.1 × the pronotal length anterad the slightly acute, projected hind angles. The median base has ~30-33 punctures each side. The pronotum is broader apically than basally; APW/BPW = 1.11-1.16. The elytra are narrowed basally, with angulate humeri, MEW/HuW = 2.10-2.22. Discal elytral striae 1-2 are shallow and closely punctured, whereas striae 3-5 are progressively less impressed laterally, the more lateral striae indicated by linear series of isolated punctures. The associated intervals 2-4 are slightly convex to flat, and the sutural interval is upraised from the disc to the apex. The vertex is glossy, with indistinct transverse sculpticells, breadth 2 × length, in small depressions. The pronotal disc is covered with an obsolete transverse microsculpture, with much of the surface glossy, and the pronotal base is glossy medially, with indistinct transverse sculpticells laterally.

Male genitalia (n = 5). Aedeagal median lobe robust, distance from parameral articulation to tip 3.5 × depth at midlength (Fig. 113A, C–D); apex parallel sided to oblique tip formed by slightly convex apical face and slightly downturned ventral margin (Fig. 114); median lobe slightly curved rightward near apex, right margin shallowly concave, left margin sinuate to elongate, parallel-sided apex with rounded tip (Fig. 113B); internal sac broadest just before base of flagellar plate, narrow at base, with one ovoid dorsal ostial microtrichial patch on right dorsal face (Fig. 113D), and 2 distinct, ovoid ventral ostial microtrichial patches on left ventral face (Fig. 113C); flagellar plate large, robust, length 0.60 × parameral articulation-tip distance (Figs 113C, G, 114).

Female reproductive tract (n = 1). Bursa copulatrix columnar with a basal constriction, length 1.37 mm, apical width 0.50 mm, basal constriction 0.4 mm (Fig. 104E); bursal walls opaque, thickly wrinkled; gonocoxite 1 with 5 apical fringe setae and 5-6 smaller setae on medial surface (Fig. 105E); gonocoxite 2 falcate with a broad lateral extension at base, 2 elongate lateral ensiform setae, apical nematiform setae on medioventral surface at 0.77 × gonocoxite length.

Lectotype.

Male (BMNH) hereby designated, labeled: Metrothorax haleakalae Type D.S. Haleakala Perkins 354 // Type // Hawaiian Is. Perkins 1904-336 // LECTOTYPE Metrothorax haleakalae Sharp J.K. Liebherr 1998 (black-margined red label).

Distribution and habitat.

During the 19th and early 20th Centuries, Mecyclothorax haleakalae was collected across the Waikamoi forest from Olinda to Ukulele Camp at elevations 1210-1675 m (Fig. 112). More recently it has been collected at Ukulele Pipeline (1525 m el.), and in yellow-pan traps along Kula Pipeline Rd (1183-1280 m el., UHIM) and Makawao-Maile Rd. (1293-1426 m el., UHIM). Aside from the yellow-pan traps, recent records have all been on koa , with beetles found under bark, or by application of pyrethrin fog to trunks of larger trees.