Mecyclothorax consanguineus, 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 : 58-60

Taxon classification Animalia Coleoptera Carabidae

(020) Mecyclothorax consanguineus sp. n. Figs 30C, 31C, 33B, 34 A–I, 35

Diagnosis.

Of species in this group characterized by broader, shorter elytra and a basally constricted, quadrisetose pronotum (Figs 28 B–C, 33B), this species can be diagnosed by the narrowed humeri, MEW/HuW = 1.91-2.04. As in the morphologically similar and partially sympatric Mecyclothorax cognatus , the pronotum is moderately constricted basally-MPW/BPW = 1.37-1.60-and the discal elytral striae are finely impressed and lined with minute punctures, the associated intervals slightly convex. The male aedeagal median lobe configuration is unique in the mucronate apex (Fig. 34 A–I). Setal formula 2 2(1) 2 2; the basal pronotal seta may be unilaterally present, though at least one seta was observed in all examined specimens. Standardized body length 4.1-5.3 mm.

Description

(n = 5). Head capsule with frontal grooves broad near clypeus, a lateral carina to anterior supraorbital seta; dorsal surface of neck flat to slightly concave; eyes moderately developed, ocular ratio = 1.39-1.51, ocular lobe ratio = 0.72-0.77; labral anterior margin with subangulate emargination, excavated 0.2 × length medially; antennae filiform, antennomeres 2-3 with sparse pelage of short setae; mentum tooth with sides acute, apex tightly rounded. Pronotum moderate ly narrow, MPW/PL = 1.15-1.25, and moderately to rather constricted basally, MPW/BPW = 1.37-1.60; hind angle right to slightly acute, projected, the lateral margin convergent to parallel just anterad the angle; median base very depressed relative to disc, shallow longitudinal wrinkles and small punctures covering surface; basal margin straight medially, slightly indented posterad laterobasal depressions; median longitudinal impression very shallow, indistinct; anterior transverse impression very shallow, broad, crossed by longitudinal wrinkles; anterior callosity nearly flat with wrinkles on the posterior half; front angles projected, tightly rounded; front and basal pronotal angles variably subequal, APW/BPW = 0.92-1.03; lateral marginal depression slightly broader at front angle, moderately narrow behind, edge upturned; laterobasal depression smooth with median extension from disc as a tubercle. Proepisternum with 6 punctures along hind marginal groove; prosternal process medially depressed, with broad lateral marginal bead. Elytra with moderately narrow humeri, the disc convex and side moderately sloped; basal groove slightly recurved to hitched humeral angle at base of elytral lateral depression; parascutellar seta present; parascutellar striole shallow, smooth anteriorly with 3 punctures in posterior portion; sutural interval equally convex as intervals 2-4 basally, more convex apically; sutural and 2nd striae of subequal depth from base to apex; sutural stria finely impressed, irregularly punctate basally, smooth and deep apically, striae 2-5 with minute punctulae on disc, striae slightly irregular along length; 7th and 8th interval of similar convexity mesad subapical sinuation; two dorsal elytral setae at 0.26 –0.28× and 0.54 –0.56× elytral length, setal impressions small, extended over ½ width of interval 3; apical and subapical setae present; lateral elytral setae arranged as an anterior series of 7 setae, a posterior series of 6 setae; elytral marginal depression moderately broad at humerus, gradually narrowed to beadlike margin at subapical sinuation; subapical sinuation shallow, nearly obsolete. Mesepisternum with ~8-9 punctures in 1-2 rows; metepisternal width to length ratio = 0.84; metepisternum/metepimeron suture distinct. Abdomen with irregular lateral wrinkles on ventrites 1-5; suture between ventrites 2 and 3 complete; apical ventrite of male with 2 marginal setae, apical ventrite of female with 4 equally spaced marginal setae plus a median trapezoid of 4 smaller, subequal setae. Legs-metatarsomere 1/metatibial length ratio = 0.21; metatarsomere 4 length along outer lobe 1.4 × medial tarsomere length, apical and subapical setae present; metatarsal dorsolateral sulci deep, broad, median area strigose to carinate. Microsculpture of vertex a transverse mesh, sculpticell breadth 2 × length; pronotal disc with reduced transverse mesh, sculpticell breadth 2 –3× length; pronotal median base with distinct isodiametric and transverse sculpticells; elytral disc with transverse mesh, sculpticell breadth 3 –4× length; elytral apex with transverse mesh, sculpticell breadth 3 × length, to transverse lines; metasternum with distinct transverse mesh; laterobasal abdominal ventrites with swirling isodiametric and transverse microsculpture. Coloration of vertex rufobrunneous; antennomere 1 flavous, antennomeres 2-3 rufoflavous, 4-11 rufobrunneous; pronotal disc rufobrunneous, pronotal apical and lateral margins rufoflavous; proepipleuron rufoflavous, proepisternum rufobrunneous; elytral disc rufobrunneous, sutural interval concolorous to rufoflavous basally, rufoflavous to flavous apically; elytral marginal depression concolorous with disc to paler, rufoflavous basally, apex slightly paler, rufoflavous to position of subapical seta; elytral epipleuron and metepisternum rufobrunneous; abdomen with ventrites medially rufopiceous, ventrites 3-6 rufoflavous laterally; abdominal apical ventrite with apical half paler, flavous; metafemur flavous; metatibia rufobrunneous.

Male genitalia (n = 15). Aedeagal median lobe distinctly curved, variably robust, with ratio of distance from parameral articulation to tip versus depth at midlength ranging 3.1-4.2 (Fig. 34A, H), but always with apex narrowly extended well beyond ostial opening, and tip denticulate; a brief indentation along apicoventral surface (Fig. 34 A–B, D–I); median lobe straight in ventral view, right margin slightly concave, left margin incurved before apparently blunt tip (Fig. 34C); internal sac generally lightly spiculated, but with indistinct ventral microtrichial patch comprised of slightly larger microtrichia (Fig. 34A); flagellar plate relatively large, length 0.45 × distance from parameral articulation to tip.

Female reproductive tract (n = 1). Bursa copulatrix columnar with apex rounded, bursa narrowed apically, length 1.05 mm, apical breadth 0.29 mm, basal breadth 0.36 mm equal to vagina breadth (Fig. 30C); bursal walls translucent with thick wrinkles; gonocoxite 1 with 3-4 apical fringe setae and 6-7 small setae on medial surface (Fig. 31C); gonocoxite 2 narrowly subtriangular with broad apex, base broadly extended laterally, 2 lateral ensiform setae with apical seta broader and longer, apical nematiform setae on medioventral surface at 0.74 × gonocoxite length.

Holotype.

Male (CUIC) labeled: HI: Maui Haleakala NW / slope Waikamoi Pres. / trans. 3 @ 1700 m el. / 10-IV-1991 sifting / litter J.K. Liebherr // HOLOTYPE / Mecyclothorax / consanguineus / Liebherr / J.K. Liebherr 2015 (black-margined red label).

Paratypes.

261 specimens (see Appendix).

Etymology.

The Latin adjectival consanguineus means related by blood, or kindred ( Brown 1956), and signifies this species’ close relationship to the previous three species.

Distribution and habitat.

Mecyclothorax consanguineus has an elevationally broad windward distribution that spans the Waikamoi Koa- ‘Ōhi‘a Mesic Forest to the lower elevation ‘Ōhi‘a-‘ Ōlapa Wet Forest, and then disjunctly extends through the Hāna Bogs to the head of Kīpahulu Valley (Fig. 35). Collection localities range 1210-2438 m elevation. A population is known from the western wall of Ke‘anae Valley, 1325 m elevation. Another marginal population occurs at Paliku, 1830 m elevation, in the eastern end of Haleakalā Crater where windward fog and moisture spill over the headwall of Kīpahulu Valley creating a lens of mesic habitat. Beetles occur in forests composed of varying mixtures of koa and ‘ōhi‘a, as well as more open, higher elevation habitats including Dubautia (kupaoa) and Leptecophylla (pūkiawe). That the species can occur in such open habitats begs the question of why it has not been recorded from the Hanawī face of Haleakalā, an area of open koa Forest with extensive Dicranopteris (uluhe) fern understory. However our sampling of the Hanawī Koa-Uluhe Formation was very cursory, leaving the question for a more intensive biotic survey.