Mecyclothorax kaumakani, 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 : 233-235

Taxon classification Animalia Coleoptera Carabidae

(095) Mecyclothorax kaumakani sp. n. Figs 117E, 118E, 121, 122 B–C, 123 F–L

Diagnosis.

The pronotal median base is more punctate in this species versus Mecyclothorax kipahulu and Mecyclothorax kuiki , with ~16-20 punctures each side (Fig. 122 B–C). The basal margin of the pronotum is smoothly curved, without dense longitudinal wrinkles as in Mecyclothorax kuiki (Fig. 122 D–E). Also, the elytra are not so widened in their apical half, leading to a lower ratio of MEW/HuW = 2.10-2.27, versus higher ratios among individuals of Mecyclothorax kuiki . The male aedeagal median lobe is most like those of Mecyclothorax kipahulu males, but the dorsal and ventral margins are more parallel on the apex, and the tip is slightly expanded into a knob (Fig. 123 F–L).

Setal formula 2 1 2 0. Standardized body length 4.6-5.0.

Description

(n = 5). [The above description of Mecyclothorax kipwilli can serve to describe this species with the following substitutions.] Eyes more convex than in Mecyclothorax kipwilli , though not diagnostically so, ocular ratio = 1.53-1.59, ocular lobe ratio = 0.79-0.87. Pronotum little transverse, MPW/PL = 1.10-1.15, variably constricted basally, MPW/BPW = 1.46-1.65. Elytra narrowly ellipsoid, lateral margins somewhat projected laterad humeri, MEW/HuW = 2.10-2.27. Metathoracic flight wing a narrow strap 1.3 × long as broad, remnant M vein present; strap not reaching hind margin of metanotum. Microsculpture of pronotal median base an indistinct to distinct isodiametric mesh across the surface between punctures; elytral disc with shallow, evident transversely stretched isodiametric mesh in transverse rows. Coloration of vertex rufous with piceous cast; pronotal disc rufopiceous; elytral disc glossy rufopiceous, sutural interval concolorous basally rufoflavous apically; elytral epipleura rufoflavous, metepisternum rufopiceous.

Male genitalia (n = 11). Aedeagal median lobe moderately robust, curved, dorsal margin distinctly convex, bulging near apex of ostial opening, distance from parameral articulation to tip 3.2 –3.5× depth at midlength (Fig. 123 F–K); median lobe straight in ventral view, with apex extended from right side, and bulging dorsal surface visible behind and to the left of apex (Fig. 123L); internal sac with large, broad basal lobe, and narrow, short apical lobe bearing the flagellar plate, the sac surface covered with microspicules only; flagellar plate very small, length 0.19 –0.20× parameral articulation-tip distance.

Female reproductive tract (n = 1). Bursa copulatrix broad, saclike, with basal lobe at vagina ventrad common oviduct, length 0.62 mm, breadth 0.36 mm (Fig. 117E); bursal walls more heavily stained and thickly wrinkled at basal lobe, more translucent and not wrinkled near apex; gonocoxite 1 with 3 apical fringe setae and 8 smaller setae along medial surface (Fig. 118E); gonocoxite 2 falcate, apex subacuminate, base broadly extended laterally with curved terminus, 2 lateral ensiform setae, apical nematiform setae on medioventral surface at 0.72 × gonocoxite length.

Holotype.

Male (CUIC) dissected and labeled: HI: Maui Haleakala N.P. / Kipahulu west rim ESE Kuiki sift humus ex ohia / 15-V-1993 lot 03 / el. 1850 m // J.K. Liebherr & / A.C. Medeiros / Collectors // HOLOTYPE / Mecyclothorax / kaumakani / Liebherr / det. J.K. Liebherr 2015 (black-margined red label).

Paratypes.

42 specimens (see Appendix).

Etymology.

The distribution of this species embraces Kīpahulu Valley, with specimens collected on Kaumakani mountain to the east of Kīpahulu Valley, and along the western rim of Kīpahulu Valley ESE of Kuiki (Fig. 121). Kaumakani is taken as the species epithet for this species, allowing the next species of this complex to be named after Kuiki.

Distribution and habitat.

Mecyclothorax kaumakani is known from Kaumakani summit to the east of Kīpahulu Valley, and from near Pu‘u Ahulili on the Manawainui Planeze west of lower Kīpahulu Valley (Fig. 121); a distribution made disjunct by the presence of Mecyclothorax kipahulu in Kīpahulu Valley. The Kaumakani records are from relatively low elevations, 1127-1165 m-whereas the Manawainui records are from 1600-1850 m elevation. Both Kaumakani and the Manawainui Planeze comprise Kula Volcanics, dated 150-750 Ka, whereas the floor of lower Kīpahulu Valley is composed of Hāna Volcanic formation Qhn2, dated to 11,000 years ago ( Sherrod et al. 2007). This history suggests that the Kaumakani and Manawainui populations of this species have not been in contact for the past 11,000 years, and that Mecyclothorax kipahulu colonized the lower valley floor from an upper Kīpahulu Valley Kula volcanic terrane during that time.