Mecyclothorax aeneipennis Liebherr

Liebherr, James K., 2015, The Mecyclothorax beetles (Coleoptera, Carabidae, Moriomorphini) of Haleakala-, Maui: Keystone of a hyperdiverse Hawaiian radiation, ZooKeys 544, pp. 1-407 : 50-51

Taxon classification Animalia Coleoptera Carabidae

(016) Mecyclothorax aeneipennis Liebherr Figs 28A, 29 A–C, 30A, 31A, 32

Mecyclothorax aeneipennis Liebherr 2005b: 123.

Diagnosis.

Among Haleakalā species of this group, Mecyclothorax aeneipennis exhibits the most quadrate pronotum, with the lateral margins little sinuate outside the laterobasal depressions (Fig. 28A); MPW/BPW = 1.17-1.29, versus MPW/BPW = 1.34-1.57 for all other Haleakalā species in this group. The elytral intervals are slightly convex, with discal striae 1-5 lined with small but distinct punctures in their basal halves to 2/3 of length. At the elytral apex, the 8th interval is more convex than the fused apical portion of intervals 5 + 7. The vertex is rufobrunneous, elytral disc slightly darker rufopiceous, and elytral disc rufopiceous with a cupreous reflection. The legs are contrastedly paler; femora flavous and tibiae flavous with a brunneous cast. Setal formula 2 2 2 2. Standardized body length 5.4-6.3 mm.

Identification

(n = 5). The eyes are moderately convex, ocular ratio = 1.41-1.50, ocular lobe ratio = 0.73-0.81. The elytra are quadrate, with the basal groove evenly recurved to the tightly rounded to subangulate humerus, the lateral marginal depression broad with margin upraised behind the humeral angle; MEW/HuW = 1.68-1.78. The dorsal body surface bears well-developed microsculpture: 1, vertex and pronotal disc with transverse mesh, sculpticell breadth 2 × length; 2; 2, pronotal median base with mixture of granulate isodiametric and transverse-mesh microsculpture; 3, elytral disc with distinct granulate isodiametric mesh; and 4, elytral apex with a transverse mesh, sculpticell breadth 3 –4× length.

Male genitalia (n = 2). Aedeagal median lobe gracile, distance from parameral articulation 4.2 × median breadth (Fig. 29A), apex narrowly extended beyond ostial opening, the tip flattened on dorsoapical aspect, tightly rounded ventrally; median lobe straight in ventral view, the right margin slightly concave before blunt tip, the left margin curved rightward to meet apical extension (Fig. 29B); internal sac with well developed, dorsal and ventral microtrichial patches, both composed of stout spicules (Fig. 29C); flagellar plate with internal face well sclerotized, length of plate 0.40 × distance from parameral articulation to tip.

Female reproductive tract (n = 1). Bursa copulatrix columnar with expanded apex, length 1.2 mm, apical breadth 0.57 mm, basal breadth 0.40 mm (Fig. 30A); bursal base translucent with thick wrinkles, apex more transparent, little wrinkled; gonocoxite 1 with 4 apical fringe setae, a small seta unilaterally present at medial apex, otherwise 7-10 small setae on medial surface (Fig. 31A); gonocoxite 2 narrowly subtriangular with broad apex and tightly rounded tip, base broadly extended laterally, 2 lateral ensiform setae with apical seta broader and longer, apical nematiform setae on medioventral surface at 0.71 × gonocoxite length.

Holotype.

Male (CUIC) designated by Liebherr (2005b). Type locality: HI: Maui, Haleakalā, Polipoli S.R.A., 1890 m el.

Distribution and habitat.

Mecyclothorax aeneipennis is restricted to the forests near Polipoli Springs on the southwest rift of Haleakalā (Fig. 32). At the time this area was surveyed it was extensively afforested with exotic gymnosperms, especially Pinus radiata . Many of these trees had lodged, creating tangles of old logs with loose bark. Beetles were found under loose bark of downed logs, under logs on the ground, or by grubbing the Pinus leaf litter; i.e., pushing the litter aside to expose an area of soil and waiting for beetles to run into the arenalike opening. Mecyclothorax aeneipennis individuals were also found in more native situations, such as in mossy litter, or among tangles of Dryopteris fern stems.