Callosides genieri Howden, 2001

Howden, H. F., 2001, A New Tribe Of Hybosorinae With A Description Of A New Species Of Callosides Howden (Coleoptera: Scarabaeidae), The Coleopterists Bulletin 55 (2), pp. 199-204 : 200-202

Callosides genieri Howden , new species

Figs. 1–7

Holotype. Male ( Fig. 1 ), length 4.2 mm, greatest width 2.2 mm. Dorsally very dark brown to black. Head closely, ocellately punctate, most punctures with fine, short, erect setae; some setae on vertex spatulate. Labrum in dorsal view almost hidden below clypeus, dorsal surface of labrum smooth, almost flat, anterior edge very slightly sinuate and fringed with long setae; ventral surface, epipharynx, ( Fig. 5 ), with double row of setae. Each mandible ( Fig. 4 ) blade­like, only lateral sides visible; apical end acute (visible after mentum removed), adjacent inner margin fringed with long setae, molar area produced inwardly to meet with opposite mandible, base apparently with mycangium. Maxilla with densely setose lacinia; palpus 4­segmented, basal segment slender. Mentum deeply, narrowly emarginate anteriorly; surface with posteriorly arcuate strigae, anterior inner edge setose; labial palpus 3­segmented. Antenna 10­segmented, club 3­segmented, basal segment not cupuliform. Clypeus arcuate, slightly more so anteriorly, edge vertical, as wide as anterior tarsal spur, shallowly grooved; long, widely spaced setae in groove; dorsal margin of edge shallowly reflexed and feebly scalloped. Vertex with low, elongate, oval tubercle on each side of midline, otherwise convex. Eye canthus obsolete, gena angulate anterior to rounded edge of eye. Pronotal shape as in Figure 1 , lacking distinct marginal groove, sides laterally explanate, thickened and scalloped in anterior threefourths of length, then abruptly constricted to posterior angles. Pronotal disc convex in anterior median half with indistinct tubercle on each side posteriorly; on posterior sixth of pronotum with four distinct tubercles in transverse arc; pronotal surface with closely spaced ocellate punctures, most punctures each with short, erect seta. Scutellum minute, surface smooth. Elytron on flattened portion of disc lacking striae, laterally with carina arising posterior to sharply toothed humerus and extending to posterior declivity; with inner short basal carina and two irregular rows of tubercles ( Fig. 1 ); surface between with large, contiguous, irregular, elongate, annular punctures; tubercles and carinae at edge of posterior declivity with distinct, erect setae. Elytra fused. Metasternal wings reduced to single straight strut slightly shorter than elytron, one edge of strut narrowly membranous. Prosternum with a distinct carina on each side extending from outer anterior edge of fore coxa to ventral edge of anterior angle, area between carinae concave and transversely strigate. Meso­ and meta­sterna very short, transverse; middle coxae almost contiguous; posterior margin of metasternum on each side very slightly arcuate. Apex of fore coxa rounded. Fore femur with slightly grooved ventral edge for reception of tibia. Fore tibia ( Fig. 2 ) slender, with two apical teeth basally very close (resembling a widely bifid tooth) and with one large and three small teeth along outer margin; apical spur slightly narrowed to apex and curved inwardly in apical half. Middle and hind tibiae slender, outer surface of each with longitudinal double row of small teeth feebly carinate between, one seta present at base of each tooth. Tarsi about half as long as adjacent tibiae, middle three tarsomeres bead­like; tarsal claws slender and simple. Male genitalia ( Figs. 6–7 ) with symmetrical parameres, short ventral lobes apically almost truncate with lateral edges angulate.

Allotype. Female, length 4.6 mm, greatest width 2.3 mm. Similar to holotype except in the following obvious features: anterior median pronotal swelling with tubercle on each side of midline elongate; tubercles on elytral disc smaller and in slightly different positions, lateral carina lower and less regular, apical tubercles smaller; fore tibia ( Fig. 3 ) apically wider than in male, apical teeth less deeply divided with apices rounded, apical half of flattened ventral surface shiny, lacking dull alutaceous areas; apical spur straight, not curved.

Type Material. Holotype, male, Ecuador: Carchı´, Bosque Arrayanes, 6.1 km E. San Gabriel, 2,830 m, 00°32'33̎N–77°47'26̎W, 2.XI.1999 –221, R. Anderson, arrayan [ Myrcianthes rhopaloides (Kunth) McVaugh ] forest litter ( CMNC) . Allotype, female, same data as holotype ( CMNC) . Paratypes, 17 males, 14 females, same data as holotype (in Canadian Museum of Nature collection = CMNC, H. & A. Howden collection, Quito Catholic Zoology Museum, Ecuador, and University of Nebraska Science Museum) .

Remarks. Males range from 4.0 to 4.5 mm in length and from 2.1 to 2.3 mm in greatest width; females vary from 4.1 to 4.6 mm in length and from 2.2 to 2.3 mm in greatest width. Variation is most evident in size and placement of the dorsal tubercles. The anterior pronotal swelling can have an oval or elongate tubercle on each side of the midline and a very small tubercle is occasionally present laterally, midway to the lateral margin. Tubercles on each elytron can differ in size and placement, but between the suture and lateral carina two irregular rows of tubercles are consistently present. The lateral carina can be unbroken to the apical declivity or interrupted in several places. The number of setae may vary, much of this probably due to abrasion. In males the ventral flattened side of the fore tibia near the apex may be smooth and shiny or dull and alutaceous. Variation does occur in the number of tubercles or teeth on the tibiae, but the variation is not pronounced.

Etymology. This species is dedicated to François Génier, an enthusiastic scarab worker and an extremely helpful colleague.

Callosides genieri can be separated from the other two species in the genus by the following key.

Figures

Figs. 1–11. Callosides spp. 1–7) C. genieri: 1) male dorsum; 2) fore tibia, male; 3) fore tibia, female; 4) right mandible, ventral view; 5) epipharynx; 6) parameres, ventral view; 7) paramere, lateral view. 8–9) C. campbelli: 8) parameres, dorsal view; 9) paramere, lateral view. 10–11) C. bartolozzii: 10) parameres, dorsal view; 11) paramere, lateral view.