Procoryphaeus wallacei ( Marseul, 1864 )

Lackner, Tomáš, 2015, Revision of the genus Procoryphaeus Mazur, 1984 (Coleoptera: Histeridae: Histerinae: Exosternini), Zootaxa 4044 (2), pp. 289-300 : 291-294

Procoryphaeus wallacei ( Marseul, 1864)

( Figs. 1–4 )

Pachycraerus wallacei Marseul, 1864: 311

Coryphaeus wallacei: Lewis (1905): 347

Procoryphaeus wallacei: Mazur (1984): 275 ; Mazur (1997): 41; Mazur (2011): 38.

Type locality. Dorey [=Manokwari], Indonesia: Papua.

Type material examined. Pachycraerus wallacei : Lectotype (present designation), ♀, side-mounted on a triangular mounting point, right protarsus and four segments of left metatarsus broken off, with the following labels: “♀” (printed); followed by: “ Coryphaeus / Wallacei / Dorey / Wall [illegible, presumably meaning ‘Wallace’]” (yellow, round label of Marseul, written); followed by: “Dor. / 260” (round label, written); followed by: “ Coryphaeus / Wallacei / Dorey” (written); followed by: “MUSEUM PARIS / COLL / DE MARSEUL 1890” (printed); followed by: “ TYPE ” (red-written label, printed); followed by: “ Pachycraerus / ( Coryphaeus ) / wallacei Marseul, 1863 / LECTOTYPE / Designated by T. / Lackner, 2015” (red label, written) ( MNHN). This species was described based on unknown number of specimens and the lectotype designation fixes the identity of the species.

Additional material examined. None.

Diagnosis. This species is delimited from all other species of the genus by almost complete fourth discal stria and the presence of sutural stria of elytra.

Re-description of the holotype. PEL: 4.50 mm; APW: 1.90 mm; PPW: 3.70 mm; EW: 4.00 mm; EL: 3.00 mm. Body ( Figs. 1 –2) castaneous with blue metallic lustre, feebly convex dorsally, venter light brown, nonmetallic, legs, antennae and mouthparts castaneous; antennal club densely covered with yellow tiny setae, yellowish-brown. All femora and tibiae covered with tiny dense pilosity; similar pilosity present also on lateral side of all pleura and sterna.

Frons ( Fig. 3) postero-medially with deep depression; occipital stria absent, frontal stria vaguely inwardly arcuate, feebly carinate, uninterrupted; supraorbital stria carinate. Disc of frons with tiny, rather dense punctuation, punctures separated by about their own diameter. Clypeus large, sub-rectangular, depressed. Antennal scape massive, approximately as large as antennal funicle; antennal club ovoid, densely tomentose. Labrum large, punctuated, sub-trapezoidal; mandibles stout, punctuate. Eyes large, bulky. Pronotum transverse, anterior insertion for head deep, pronotal margin slightly elevated, marginal stria complete, thin. Lateral side of pronotum with variolate confluent punctuation, forming a narrow such band also along anterior pronotal margin, between this punctuate band and lateral pronotal margin a thin glabrous to semi-glabrous band present. Rest of pronotum covered with regular very fine punctuation, punctures separated by several times their own diameter. Pronotal hypomeron with several rows of dense microscopic setae, intermingled with scattered punctuation. Pre-scutellar area with vague tiny tubercle; scutellum tiny, but visible.

Elytra widest approximately behind humeri, elytral epipleura with scattered microscopic punctuation, marginal elytral stria carinate, stopping short of elytral apex. Apical elytral stria vaguely marked, almost indiscernible, but probably present; marginal epipleural stria carinate on basal third, next impressed deeply into cuticle and evanescent. Outer subhumeral stria present as a short fragment on basal elytral third; between it and marginal elytral stria a row of punctures present. Inner subhumeral stria joined with humeral elytral stria creating thus a complimentary dorsal elytral stria running parallel to first dorsal elytral, but somewhat shortened apically. Elytra with four sinuate impunctate and slightly carinate discal striae, almost of the same length, stopping short of elytral apex; first stria somewhat shorter than the rest. Faint traces of intermittent fifth discal stria present; its base with a ‘hooked’ appendix, surface around it distinctly depressed; sutural elytral stria basally faintly connected to the ‘hooked’ appendix of faint fifth discal elytral, becoming clearly impressed approximately on elytral half, stopping short of elytral apex. Entire elytral disc with fine punctuation; punctures becoming denser and larger towards elytral suture, separated by about twice to several times their own diameter.

Propygidium very large, almost as wide as long, covered with alutaceous microsculpture and scattered fine punctures becoming denser apically; pygidium much smaller than propygidium, sub-triangular, convex, covered with scattered fine punctuation, punctures separated by about twice to several times their own diameter.

Prosternal lobe ( Fig. 4 ) bisinuate, anterior margin inwardly arcuate medially, marginal stria of prosternal lobe complete, well-impressed, disc of prosternal lobe covered with punctuation; punctures separated by several times their diameter. Prosternal keel almost even, slightly concave on its basal half, covered with scattered fine punctures; carinal prosternal striae straight and running parallel between procoxae, thence slightly diverging, converging and united apically. Surface between prosternal keel and well-impressed, carinate and sub-parallel lateral prosternal striae distinctly depressed, creating a curious ‘index finger-like’ depression. Prosternal keel laterally delimited by a definite stria situated between keel and lateral prosternal striae. Mesoventrite ( Fig. 4 ) rather small, transverse, anterior margin with anterior projection; marginal mesoventral stria complete; disc of mesoventrite with scattered microscopic punctuation; meso-metaventral suture well-visible, straight; mesometaventral sutural stria absent. Metaventrite ( Fig. 4 ) almost even, covered with scattered microscopic punctuation more prominent along slight antero-median depression; lateral disc of metaventrite with sparse foveolate punctures separated by several times their diameter intermingled with much denser finer setigerous punctuation and alutaceous microsculpture. Metepisternum with dense fine punctuation; punctures separated by about their own diameter. Lateral metaventral stria sub-carinate, outwardly arcuate, reaching approximately 2/3 of metaventral length apically.

First visible abdominal ventrite slightly depressed on its basal half, apical half slightly convex, surface with scattered microscopic punctuation. Outer stria of first abdominal ventrite vaguely marked on its basal half, almost indiscernible, next evanescent.

Legs. All coxae rather large, procoxae massive, transverse; all femora sub-globular, covered with dense microscopic amber setae; all tibiae flattened and slightly dilated, covered with similar setae to that of femora; protibia on outer margin apically with a tiny denticle followed by two widely-spaced triangular teeth topped by denticle; protibial groove very deep and prominent; protibial spur large, stout, growing from near tarsal insertion supplemented by another much smaller spur growing out directly from anterior protibial margin. Meso-and metatibiae on outer margin without teeth or denticles, except for two tiny denticles placed on top of a small triangular tooth at apex; both meso-and metatibial spurs well developed.

Male unavailable.

Remarks. This description is based on the female holotype, for two reasons: 1) absence of male terminalia that would better delimit the species’ unity, and 2) presence of four discal as well as sutural striae on the elytra. This last character is not present in any of the remaining examined specimens, even from the island of New Guinea. It is possible that the holotype specimen is simply an aberrant one and that the prevailing form is with three wellmarked discal and wanting (or vague) sutural stria on the elytra. I am hesitant to ascribe the specimens without sutural stria and wanting (intermittent, indiscernible or vague) fourth discal elytral stria to this species, and prefer to list them under the species P. vi ol a ce u s. Other morphological characters show little or no variation and without examining male genitalia (since there are no males in the type series) between New Guinean and other (Java, Borneo, Thai etc.) populations the species delimitations are unclear. I prefer to opt for the more conservative approach and keep the species separated. For the above-mentioned reasons the following two species are provided only with the diagnostic descriptions providing characters that differ from the holotype of P. wallacei .

Figures

FIGURE 1. Procoryphaeus wallacei (Marseul, 1864) habitus, dorsal view. FIGURE 2. ditto, ventral view.

FIGURE 4. Procoryphaeus wallacei (Marseul, 1864) prosternum, mesoventrite + metaventrite.