Chlamydopsis chadster Caterino, 2007

Barman, E. H., Michat, M. C., Alarie, Y. & Wolfe, G. W., 2007, Figs. 16 – 17. 16 in A Description of the First Instar of Hoperius planatus Fall, 1927 (Coleoptera: Dytiscidae: Colymbetinae: Colymbetini), with Phylogenetic Implications, The Coleopterists Bulletin 61 (3), pp. 327-333 : 327-333

Chlamydopsis chadster Caterino , New Species

( Figs. 1A, B )

Holotype male. [ Indonesia]: ‘‘ IRIAN JAYA: Japen Isl., Kontiunai [136 ° 20 9 E, 1 ° 47 9 S], 600–700 m, 25.XII.2000, leg. A. RIEDEL’’; deposited in SMNS.

Paratype. 1 male, same data as type; SMNS .

Diagnosis. This species is easily distinguished from the other two known New Guinean Chlamydopsis by it’s lack of acute median pronotal tubercle. Both C. papuae Lewis and C. jayawijaya Caterino have a prominent median tubercle. The trichome opening of these latter two species is also nearly circular, and barely visible in lateral view, whereas in C. chadster , the trichome opening is much larger, transversely oval, and deeply incises the epipleuron.

Description. L: 2.43; W: 1.68; E/Pn L: 1.69; E/Pn W: 1.35; Pn W/L: 1.38; E L/W: 0.91; Pr/Py: 1.29; Sterna: 0.62, 0.22, 0.75; Tibiae: 1.09, 1.31, 1.46. Body subquadrate, about two-thirds as wide as long, dark rufescent, reticulopunctate to reticulostrigose throughout, with sparse fine setae on most surfaces; head weakly proclinate, sloping posterad from vertex to labrum, when retracted, with frons about two-thirds as wide as long, with sides weakly but evenly outwardly arcuate, surface coarsely reticulate, integument within depressions smooth, shining, and elevated ‘reticulae’ transversely microsculptured bearing scattered setae; labrum convex, almost four times as wide as median length, with dense reticulate microsculpture, lacking larger reticulations, glabrous; mandibles strongly angulate about one-third from base, with few setae near angle, basal two-thirds microsculptured, apices smooth; antennal scape subtriangular, bluntly angulate just basad of midpoint, with proximal outer edge weakly emarginate, distal outer edge nearly straight, rounded distally; antennal funicle (of male) about three-fourths length of scape, with antennomere 2 cylindrical, about half length of antennomere 3, antennomeres 4–8 subequal, less than one-half length of antennomere 3; antennal club (of male) subcylindrical, about 1.5 times length of scape.

Prothorax about 1.5 times as wide as median length, with lateral and anterior margins strongly and continuously elevated, sides slightly diverging anterad, projecting acutely at anterolateral corners, and at anterior midpoint, lateral portions of anterior margin oblique, strongly convergent to weakly elevated median point; posterior margin angulate at middle, obliquely diverging to sides, with deep sulcus paralleling margin, the pronotal disk projecting slightly posterad over this sulcus at middle; middle of pronotal disk slightly elevated along midline, depressed at sides, evenly coarsely reticulopunctate, shining with punctures, with faint polygonal microsculpture and sparse setae on elevated reticulae; prosternum short, with total median length less than one-half width, anterior margin broadly emarginate across middle, with moderately deep marginal groove, this groove diverging from anterior margin at sides, meeting outer groove delimiting leg depression; prosternal keel depressed behind margin, rising (as viewed from 330 below) posterad to mesosternum, with lateral margins strongly grooved, and posterior margin deeply emarginate.

Elytra conjointly approximately square, with sides parallel and posterior margin straight; anteriorly deeply emarginate by posterior projection of pronotum; humeral trichomes very strongly elevated, height above pronotum (in lateral view) nearly equal to anterior pronotal height; anterior elevation with oblique groove extending from anterolateral corner mediad to inner edge of trichome; elevation with outer edge arcuate, converging to straighter inner margin, meeting at a bluntly rounded apex, inner posterior surface of anterior elevation bearing dense continuous fringe of golden setae; posterior elevation similar in shape though less strongly elevated, its apex posteromediad of that of anterior elevation, completely lacking setae; elytral mediobasal depression about one-third elytral width across humeri, bearing strongly transverse, blunt carinae, these rising from trichome to midline; elytral disk strongly convex at middle behind trichomes, strongly longitudinally strigose, with sparse setae on raised strigae; epipleuron shallowly reticulate on side of anterior humeral elevation, and with faint longitudinal strigae along upper posterior edge, otherwise impunctate, smooth, with sparse scattered setae; elytral marginal stria complete around epipleural and posterior edges, absent from anterior margins and basal one-third of sutural margin, subparallel to margins where present.

Mesosternum about one-third length of prosternum, arcuately projecting at middle, with disk coarsely reticulate; mesometasternal suture deeply impressed, and faintly doubled by anterior marginal metasternal stria, distinct from suture at middle; metasternal disk mostly smooth, with few faintly impressed punctures along anterior and posterior margins, with discontinuous and disorganized polygonal microsculpture in middle portion; median metasternal suture visible but unimpressed; posterior marginal striae obsolete between metacoxae; abdominal ventrite 1 with more numerous large, shallow punctures than metasternum, though with impunctate areas conspicuous, with faint microsculpture; postmetacoxal striae obsolete between coxae.

Legs elongate, slender, all outer surfaces with faint polygonal microsculpture; femora widened very slightly to apices, margined and bearing row of short setae along posterior edges; protibia slender, outer margin acutely angulate one-third from base; outer margins of meso- and metatibiae more bluntly angulate nearer midpoints; tarsi long, about two-third lengths of respective tibiae, bearing few ventral spines near apices of each tarsomere; tarsal claws evenly weakly curved.

Propygidium vertical, only slightly longer and wider than pygidium, deeply depressed along anterior margin, weakly convex behind, evenly reticulopunctate, with fine polygonal microsculpture on raised reticulae; pygidium nearly flat, slightly convex at base, weakly depressed along posterolateral margins, texture similar but shallower than that of propygidium.

Remarks. I take great pleasure in naming this species in honor of Mr. Chad Dreier, in recognition of his strong support of education and research activities at the Santa Barbara Museum of Natural History. The name is a noun in apposition.

Figures

Fig. 1. Lateral (A) and dorsal (B) views of Chlamydopsis chadster, new species; lateral