Mecyclothorax filipoides, 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 : 283-286

Taxon classification Animalia Coleoptera Carabidae

(112) Mecyclothorax filipoides sp. n. Figs 149C, 153 A–C, 154A, 155A, 156

Diagnosis.

Among Haleakalā’s Mecyclothorax palustris group species, Mecyclothorax filipoides stands out based on the disparate dorsal microsculpture: 1, head and pronotum with glossy surfaces, their microsculpture respectively a shallow transverse mesh, and obsolete transverse mesh to transverse lines; 2, elytral disc and apex with coriaceous surface comprised of isodiametric or slightly transversely stretched sculpticells arranged in irregular transverse rows. The elytral disc and lateral intervals are rufobrunneous with the elytral apex only indistinctly paler. The discal elytral striae are shallow, with the punctures of the inner striae isolated, and the sutural stria the most complete (Fig. 149C). Setal formula 2 1 2 0. Body size is large among species of the group; standardized body length 4.7-5.5 mm.

Description

(n = 5). Head capsule with frontal grooves narrow and deep anteriorly, sinuous laterally and shallower until terminated posteriorly mesad thin carina that borders depression surrounding anterior supraorbital seta; dorsal impression of neck slightly concave; ocular lobes obtusely protruded from gena, eyes large, ocular ratio = 1.52-1.59, ocular lobe ratio = 0.82-0.88; labral anterior margin angularly emarginate 1/7 labral length; antennae filiform, antennomeres 2-3 with sparse pelage of short setae; mentum tooth with sides acute, apex tightly rounded. Pronotum appearing quadrate, MPW/PL = 1.12-1.19, lateral margins slightly convergent anterad acute hind angles for 1/6 of pronotal length, base moderately constricted, MPW/BPW = 1.47-1.56; median base slightly depressed medially, more so laterally, ~25 isolated punctures each side, those along juncture of base and disc elongate; basal margin trisinuate, slightly convex medially and expanded posteriorly behind laterobasal depressions; median longitudinal impression shallow, finely incised, smooth, continued onto median base; anterior transverse impression broad, very shallow medially, well-marked laterally mesad front angles; anterior callosity flat, gradually elevated from transverse impression to front margin, crossed by minute longitudinal wrinkles; front angles projected, narrowly rounded; pronotal apical width slightly less than pronotal basal width, APW/BPW = 0.95-0.99; lateral marginal depression moderate, edge beaded laterally to basal sinuation, more broadly upraised outside laterobasal depressions; laterobasal depression minutely punctate, continuous with lateral depression. Proepisternum with 4 distinct punc tures along hind marginal groove; prosternal process with broad median depression, lateral margins broadly margined between coxae. Elytra subquadrate, disc convex, sides distinctly sloped to margins; basal groove evenly curved to subangulate to angulate humerus defined by hitch in margin at juncture of narrow basal groove and broader lateral marginal depression, MEW/HuW = 2.09-2.24; parascutellar seta present; parascutellar striole with 5 large punctures, striole shallow to interrupted between punctures; sutural interval broadly domed to elevated sutural juncture; sutural stria punctate, deeper than 2nd stria on disc, finely incised, deep, and smooth apically, where 2nd stria is broader and shallower, and irregularly interrupted; discal striae 2-4 progressively shallower laterally with elongate punctures progressively isolated, associated intervals flat, appearing concave on middle of disc; striae 1, 2, and 7 present on elytral apex, striae indicated by series of isolated punctures, 8th interval slightly more convex than 7th mesad subapical sinuation; 2 dorsal elytral setae at 0.15 –0.18× and 0.53 –0.60× elytral length, setal impressions small, shallow, spanning ½ width of interval 3; lateral elytral setae arranged in anterior series of 7 setae and posterior series of 6 setae; elytral marginal depression moderately broad, margin little upraised even near subapical sinuation; subapical sinuation shallow, concavity symmetrical. Mesepisternum with ~18 punctures in 2-3 rows; metepisternal width to length ratio = 0.81; metepisternum/metepimeron suture distinct. Abdomen with irregular lateral wrinkles on ventrites 1-5, and lateral depressions on ventrites 3-6; suture between ventrites 2 and 3 reduced laterally, effaced; apical male ventrite with 2 marginal setae and apical female ventrite with 4 equally spaced setae and median trapezoid of 4 subequal, short setae. Legs-metatarsomere 1/metatibial length ratio = 0.20; metatarsomere 4 length along outer lobe 1.3 × medial tarsomere length, apical and subapical setae present but short; metatarsal dorsolateral sulci broad, shallow, median area subcarinate. Microsculpture of vertex a shallow transverse mesh, sculpticell breadth 2 –3× length; pronotal median base glossy, shallow transverse sculpticells laterally near punctures; metasternum with shallow transverse mesh; laterobasal abdominal ventrites with swirling isodiametric and transverse sculpticells. Coloration of vertex rufobrunneous with piceous cast; antennomeres 1-3 rufoflavous, 4-11 rufobrunneous; pronotal disc rufobrunneous, lateral margins narrowly, and base and apex rufoflavous; proepipleuron rufoflavous, proepisternum rufobrunneous with piceous cast; elytral disc rufobrunneous, sutural interval basally rufous, concolorous on disc, apically rufoflavous; elytral marginal depression rufoflavous outside humerus, concolorous with disc posteriorly; elytral epipleuron rufoflavous, metepisternum rufobrunneous; abdominal ventrites 1-5 rufopiceous medially, rufoflavous laterally, apical ¾ of apical ventrite 6 rufoflavous; metafemur flavous; metatibia rufoflavous.

Male genitalia (n = 3). Aedeagal median lobe very slender immediately distad basal bulb, greatly expanded along dorsal margin of ostial opening, distance from parameral articulation to tip 3.2 × greatest depth (Fig. 153A, C), apex extended as an asymmetrical spoon with blunt ventral projection; median lobe with apex directed rightward in ventral view (Fig. 153B), bulging dorsal margin (Fig. 153A) visible as convex apical prominence in this view; internal sac short, narrow, with broad, diffuse dorsal ostial microtrichial patch near base (Fig. 153C); flagellar plate small, length 0.20 × parameral articulation-tip distance (Fig. 153C).

Female reproductive tract (n = 1). Bursa copulatrix broadly columnar with small apical cap, overall length 0.78 mm, cap 0.29 mm broad × 0.17 mm long, shaft breadth 0.43 mm (Fig. 154A); apical cap finely wrinkled, shaft translucent with thick wrinkles; gonocoxite 1 with 3-4 apical fringe setae, a curved seta just basad medioapical angle and 7 smaller setae on medial surface (Fig. 155A); gonocoxite 2 falcate with acuminate tip, basal extension straight, 2 lateral ensiform setae, apical nematiform setae on medial surface at 0.68 × gonocoxite length.

Holotype.

Male (BPBM) labeled: N.W. / Haleakala / VIII-18-37 Maui // 6000 ’–6500’ // Beating / ECZimmerman / Collector // HOLOTYPE / Mecyclothorax / filipoides / Liebherr / det. J.K. Liebherr 2015 (black-margined red label).

Paratypes.

54 specimens (see Appendix).

Etymology.

This species appears not unlike Mecyclothorax filipes (Sharp) of Lāna‘i ( Liebherr 2009b), leading to filipoides as the species epithet. The adjectival stem filipes refers to the possession of threadlike feet ( Jaeger 1955).

Distribution and habitat.

Mecyclothorax filipoides is distributed over a broad range of elevations-1310-1980 m-across the Waikamoi area (Fig. 156). Specimen collections are equally frequent from koa and ‘ōhi‘a, with beetles also associated with rotten Cheirodendron ('ōlapa) trunks. Other collecting events involved beating vegetation at night, sifting litter, or capture in yellow-pan traps.