Mecyclothorax tauberorum, 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 : 291-292

Taxon classification Animalia Coleoptera Carabidae

(115) Mecyclothorax tauberorum sp. n. Figs 154D, 155D, 158 C–D, 161 A–D, 163

Diagnosis.

This is the second species (Fig. 158 C–D), along with Mecyclothorax palustroides (Fig. 149B) and Mecyclothorax pau (Fig. 158E), that comprise a taxonomic triplet characterized by extremely similar external appearance. Individuals of this species exhibit laterally darker elytra, with intervals 8-9 gradually paler to rufobrunneous compared to the rufopiceous disc; a condition shared with Mecyclothorax pau . There may be a broader pale area behind the humerus, but at midlength the lateral intervals 7-8 are indistinctly paler. The pale margin of the elytral apex is narrow, at most extended to a line traversing the subapical sinuations. The pronotal median base appears less depressed relative to the disc due to its less developed punctation, with ~12 small, isolated punctures each side and few or no elongate punctures along the juncture of disc and base. And the elytral microsculpture is an upraised transverse mesh comprising a mixture of isodiametric and transverse sculpticells, their individual surfaces partially upraised so that the surface is alutaceous; a condition shared with Mecyclothorax palustroides . The male aedeagal median lobe is bluntly rounded apically (Fig. 161 A–D). Setal formula 2 1 2 0. Standardized body length 3.9-4.5 mm, diagnostically smaller than the body size of the sympatrically distributed Mecyclothorax palustroides ; standardized body length 4.6-5.5 mm.

Description

(n = 5). [The above description of Mecyclothorax palustroides can serve to describe this species. All diagnostic characters are presented above, so only the various recorded ratios are presented below.]

Eyes moderately convex, ocular ratio = 1.48-1.54, ocular lobe ratio = 0.77-0.85. Pronotum slightly transverse, MPW/PL = 1.09-1.21, variably constricted basally, MPW/BPW = 1.52-1.71; pronotal apical width greater than basal width, APW/BPW = 1.07-1.15. Elytra subovoid, MEW/HuW = 2.13-2.35.

Male genitalia (n = 6). Aedeagal median lobe short, squat, distance from parameral articulation to tip 3.2 –3.3× depth at midlength (Fig. 161A, C); apex bluntly rounded and not extended beyond ostial opening; median lobe slightly curved rightward near blunt apex, the right and left margins subparallel in ventral view (Fig. 161B); internal sac with ventral surface densely covered with pelage of shaggy microtrichia (Fig. 161D), the sac only 1.5 × as long as flagellar plate; flagellar plate large, length 0.61 × parameral articulation-tip distance.

Female reproductive tract (n = 1). Bursa copulatrix vase shaped, parallel sided with basal constriction, overall length 1.14 mm, midlength breadth 0.40 mm, basal constriction 0.22 mm broad (Fig. 154D): bursal walls translucent, thickly wrinkled; gonocoxite 1 with 4 apical fringe setae and 4 smaller setae on medial surface (Fig. 155D); gonocoxite 2 falcate with narrowly rounded apex, thick basal extension curved at terminus, 2 elongate lateral ensiform setae, apical nematiform setae on medioventral surface at 0.71 × gonocoxite length.

Holotype.

Male (CUIC) dissected and labeled: HI: Maui Haleakala NW / slope Waikamoi Pres. / trans. 3 @ 1700 m el. / 8-V-1991 scraping / ohia w/ moss & dirt // J.K. Liebherr / collector // 1 // Mecyclothorax tauberorum ♂ #5 / det. J.K. Liebherr 2014 // HOLOTYPE / Mecyclothorax / tauberorum / Liebherr / det. J.K. Liebherr 2015 (black-margined red label).

Paratypes.

HI: Maui: Koolau For. Res., Waikamoi flume tanks [label Waikamoi N.C.P.], 1275 m el., 31-v-1993, Tauber/Tauber (CUIC, 11); Waikamoi N.C.P., Honomanu drainage, transect 3, Metrosideros with moss, 1700 m el., 13-v-1993 lot 01, Liebherr (CUIC, 1), moss on Metrosideros trunk, 1830-1860 m el., 7-v-1991 lot 09, Kavanaugh (CAS, 1), scraping Metrosideros bark/moss, 1820-1850, 07-v-1991 lot 02, Liebherr (CUIC, 1), scraping Metrosideros humus/moss, 1700 m el., 08-v-1991 lot 03 Liebherr (CUIC, 4).

Etymology.

This species is named to honor Dr. Catherine A. Tauber and Prof. Maurice J. Tauber for their collegiality and friendship, and for their contributions to Hawaiian entomology, evolutionary biology, and the study of Neuroptera worldwide.

Distribution and habitat.

Mecyclothorax tauberorum is known from only three localities; in the Honomanu drainage at 1700 m and 1820-1860 m elevations, and in the Waikamoi drainage at 1275 m elevation (Fig. 163). All specimens have been associated with mossy ‘ōhi‘a trunks, and were collected by scraping bark and moss, or by beating vegetation.