Mecyclothorax anchisteus, 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 : 56-58

Taxon classification Animalia Coleoptera Carabidae

(019) Mecyclothorax anchisteus sp. n. Figs 32, 33A

Diagnosis.

This species is easily diagnosed by the distinctly cordate pronotum, MPW/BPW = 1.57, with glabrous hind angles. The pronotal lateral margins are distinctly convergent anterad the acute and acuminately projected hind angles (Fig. 33A). The head, pronotum, and elytra are a uniformly dark rufous. The eyes are moderately convex, ocular ratio = 1.43, but rather small, covering only ¾ of the little protruded ocular lobe; ocular lobe ratio = 0.76. The elytra are broadly subovoid, with the humeri narrowly rounded; MEW/HuW = 2.0. The discal elytral intervals are covered with irregular transverse-line microsculpture, the lines not joined into a mesh. Setal formula 2 1 2 1[sae]. Standardized body length 5.1 mm.

Description

(n = 1). Head capsule with frontal grooves broad near clypeus, a lateral carina to anterior supraorbital seta; dorsal surface of neck slightly concave; labral anterior margin broadly, shallowly emarginate, antennae filiform, sparse pelage of short setae present on antennomeres 2-3; mentum tooth with sides acute, apex tightly rounded. Pronotum moderately transverse, MPW/PL = 1.26; median base depressed relative to disc, with small punctures and lateral wrinkles; basal margin straight, slightly indented posterad laterobasal depressions; median longitudinal impression shallow, very finely incised at depth; anterior transverse impression very shallow, narrow, crossed medially by longitudinal wrinkles; anterior callosity nearly flat, crossed by indistinct wrinkles; front angles slightly projected, tightly rounded; anterior width greater than basal width, APW/BPW = 1.07; lateral marginal depression narrow throughout, margin upturned to finely beaded before sinuation; laterobasal depression smooth, laterally elevated to projected lateral margin. Proepisternum with smooth hind marginal groove; prosternal process medially depressed, a broad lateral marginal bead that is narrowed anteriorly. Elytra with convex disc, sides depressed; basal groove slightly recurved to broadly rounded humeral angle; parascutellar seta present; parascutellar striole continuous, with 4-5 punctures; sutural interval more convex than intervals 2-4, sutural juncture upraised; sutural and 2nd striae of subequal depth from base to apex; striae 1-8 complete, stria 7 slightly shallower, associated intervals moderately convex; discal striae with slightly irregular punctulae basally, smooth and deep apically; 7th and 8th intervals of similar convexity mesad subapical sinuation; 2 dorsal elytral setae at 0.27 × and 0.49 –0.52× elytral length; setal impressions extended over 2/3 width of interval 3; subapical seta present, apical seta absent; lateral elytral setae arranged in anterior series of 7 setae and posterior series 6 setae; elytral marginal depression narrow throughout, margin slightly upraised at humerus; subapical sinuation shallow, broad. Mesepisternum with ~5 punctures in 1 row; metepisternal width to length ratio = 0.81; metepisternum/metepimeron suture distinct. Abdomen with irregular lateral wrinkles on ventrites 1-5; suture between ventrites 2 and 3 complete; apical ventrite of female with 4 equally spaced marginal setae and a median trapezoid of 4 setae, the basal pair longer. Legs-metatarsomere 1/metatibial length ratio = 0.22; metatarsomere 4 length along outer lobe 1.37 × medial tarsomere length, apical and subapical setae present; metatarsal dorsolateral sulci very broad, median area rough to carinate. Microsculpture of vertex with isodiametric to slightly stretched isodiametric sculpticells in transverse rows; pronotal disc with transverse mesh, sculpticell breadth 3 –4× length; pronotal median base with isodiametric to transverse sculpticells; elytral disc with irregular transverse lines, apex with more regular transverse lines; metasternum with distinct transverse mesh; laterobasal abdominal ventrites with swirling isodiametric and transverse microsculpture. Coloration of antennomere 1 flavous, antennomeres 2-3 rufoflavous, 4-11 rufobrunneous; proepipleuron and proepisternum rufobrunneous; elytral apex paler than disc, rufoflavous to position of subapical seta; elytral epipleuron rufoflavous laterally, rufobrunneous ventrally, metepisternum rufobrunneous; abdomen medially rufobrunneous, laterally rufoflavous; abdominal apical ventrite 6 with apical 1/3 paler, flavous; metafemur flavous with piceous cloud covering basal half; metatibia rufoflavous with brunneous cast.

Female reproductive tract. The lone female holotype was not dissected.

Holotype.

Female (NMNH) labeled: HI:Maui Haleakala N.P. / Kipahulu Vy. West Camp / 20-V-1998 lot01 1950 m / el. pyrethrum fog mossy / ohia D.A. Polhemus // HOLOTYPE / Mecyclothorax / anchisteus / Sharp / J.K. Liebherr 2015 (black-margined red label).

Etymology.

The species epithet anchisteus is Greek for next of kin ( Jaeger 1955), signifying this species’ close affinities to Mecyclothorax cognatus , Mecyclothorax affinis , and Mecyclothorax consanguineus .

Distribution and habitat.

This species is known from a single specimen collected at the head of Kīpahulu Valley (Fig. 32) after application of pyrethrin fog to a mossy ‘ōhi‘a tree.