Randersonia schwarzi Chamorro & Presnall, 2022

Chamorro, M. Lourdes & Presnall, Tara Milovana, 2022, Randersonia Chamorro, a new genus with two new species of North American Cryptorhynchinae (Coleoptera: Curculionidae), Zootaxa 5222 (6), pp. 591-599 : 593-597

Randersonia schwarzi Chamorro & Presnall sp. n.

( Figs 2 , 3 )

http://zoobank.org/ urn:lsid:zoobank.org:act:8821FB6B-388B-4AD2-B9B0-AC2A5ED619A6

Type Locality. Mexico, Tampico .

Material examined. HOLOTYPE, ♁: Tampico [22.278167, -97.867723, uncertainty 63,891 m]/ Mexico 6 12 [1909] // EASchwarz / Collector // [yellow paper, handwritten presumably by Buchanan] Paracamptus sp. nov. // USNMENT01448951 // HOLOTYPE Randersonia schwarzi / Chamorro & Presnall 2022 ( USNM) ; PARATYPES (17): USNMENT01448832 same data as holotype; USNMENT01448950, USNMENT01448824– USNMENT014488230 date 14 12; USNMENT01448831 date 16 12. USNMENT01448829 includes eight paratypes glued to three cards on a single pin (one card with 3 specimens will be deposited at CMNC and one card with two specimens will be deposited at UNAM); USNMENT01448824 is the dissected male ( Fig. 3 ) .

Diagnosis: Randersonia schwarzi can be distinguished from R. cartwrighti by presence of a visible scutellum, the medially broader elytra; slightly more developed humeri; by the slightly wider rostrum with pubescent scales beyond antennal insertion; by the funicular segments (desmomeres) each two times wider than long, making the funicle shorter. The pronotum is 1.25 times longer than wide, being widest at the base, whereas in R. cartwrighti the pronotum is two times longer than wide and widest at the middle, the basal squamose scales are absent, and the anterior margin of the pronotum is not feebly emarginate. The ommatidia are larger, making the compound eye appear with fewer facets but pronounced, whereas in R. cartwrighti the ommatidia are relatively smaller and the eye is more flush with the frons. Randersonia schwarzi has ventrites 1+2 as long as wide, unlike R. cartwrighti , which has ventrites 1+2 two times longer than wide.

Description. Holotype male, body elongate-oval, 1.25 mm in length (exclusive of head and rostrum), 0.8 mm in width (measured at widest point), depth 0.4 mm, color light reddish brown. Head not impressed, with scales throughout. Rostrum straight, slightly longer than head, punctate, about as long as pronotum, dorso-ventrally flattened, scales present throughout, antennae inserted at a point about one-third from base. Antennae light-brown, funicle with seven desmomeres, first desmomere almost as long as 2–4 combined, second desmomere subequal to third. Eyes with ommatidia prominent, globose. Pronotum 1.5 times longer than wide, anterior margin evenly convex, widest point basally; punctate throughout with smaller punctures anterad; light brown, erect, clavate scales present throughout; plumose scales within punctures, absent laterally and along basal margin. Elytra subcylindrical, humeri weakly developed; scutellum visible, small, trapezoidal. Venter clothed with clavate scales, ventrites 1 and 2 as long as wide. Median lobe as in figure 3.

Etymology. This species is named in honor of Eugene A. Schwarz (1844–1928), former United States Department of Agriculture (USDA) entomologist at the National Museum of Natural History (USNM), co-founder of the Entomological Society of Washington and the collector of the only known specimens of this species.

Figures

FIGURE 2. Habitus of Randersonia schwarzi Chamorro & Presnall, sp. n., male.A—lateral view; B—dorsal view; C—ventral view.

FIGURE 3. Median lobe of Randersonia schwarzi Chamorro & Presnall, sp. n. A—lateral view; B—dorsal view.