Panscopus (Panscopus) alternatus Schaeffer, 1908

Spanton, Timothy G. & Anderson, Robert S., 2016, A Taxonomic Revision of Weevils of the Genus Panscopus Schönherr (Coleoptera: Curculionidae: Entiminae: Tropiphorini), The Coleopterists Bulletin (mo 15) 70, pp. 1-86 : 14-16

Panscopus (Panscopus) alternatus Schaeffer, 1908

( Figs. 3 , 29 , 54 , Map 3 )

Panscopus alternatu s Schaeffer 1908: 214. Blatchley 1916: 105; O’ Brien and Wibmer 1982: 62; Ciegler 2010: 200.

Panscopus (Panscopus) alternatus ; Pierce 1913: 391; Leng 1920: 312; Buchanan 1927: 27, 1936: 3; Schenkling and Marshall 1931: 40; Blackwelder 1939: 66.

Type Material. Male lectotype ( USNM Cotype No. 42481): “ Black Mountain , N.C., IX.13, Brooklyn Museum Coll. 1929”. Schaeffer (1908) described this species from an unspecified number of specimens, thus a lectotype is here designated .

Specific Epithet. The source is the Latin noun “ alternus”, meaning first one, then the other, i.e., alternating; plus “–atus” to form an adjective, nominative case, probably intended to describe the alternating elevated, or slightly keeled, and flat elytral intervals exhibited by adults of this species.

Diagnosis. Panscopus (sensu stricto) weevils with alternate elytral intervals costate and setose, even intervals incompletely setose or nearly without setae, scales of serial punctures on elytra narrow, almost seta-like on lateral portions of elytra, and corbel of tibia 3 effaced.

Redescription. Females: Length 6.4–7.9 mm (n = 6); width across elytra 2.8–3.4 mm (n = 8). Males: Length 6.0– 7.3 mm (n = 10); width across elytra 2.3–2.6 mm (n = 12). Head: Broad, transverse impression immediately in front of eyes between frons and rostrum, rostrum tricarinate dorsally, with pronounced medial longitudinal carina and lateral longitudinal carinae, one on each side, visible through vestiture of dense, appressed scales and sparse semi-erect setae, rostral carina less pronounced in males, angular nasal plate indistinct, merging with punctate region near apex of rostrum. Antennae: Scape clothed with appressed scales and decumbent setae, together nearly obscuring integument over most of its length; antennomeres 2–8 slightly elongate, 8 obviously longer than broad. Pronotum: Slightly wider than long, widest slightly in front of middle; median longitudinal sulcus present, dorsal surface irregularly rugosetuberculate, vestiture of irregular layer of appressed scales and irregular, sparsely distributed semi-erect to decumbent setae. Elytra: Approximately 1/2 longer than combined width, together slightly wider than prothorax, parallel-sided at middle third; in dorsal view, narrowed in curve toward apex; declivity, in lateral view, evenly curved toward apex; alternate elytral intervals raised, carinate, even intervals nearly flat, alternate (raised) intervals with irregular double row of decumbent, thin setae; even intervals with incomplete single row of setae, serial punctures each with thin, short seta, not a scale; surface vestiture of dense, appressed scales obscuring most of integument, scales brown to beige, some cupreous. Legs: Tibia 1 with row of denticles on ventral margin in apical third, setae inserted therein thin and hair-like, not stout spines; tibiae 2 and 3 without denticles or stout spines; femora and tibiae with dense vestiture of flat scales, nearly obscuring integument, and sparse decumbent setae; tibia 3 with corbellar area open, not enclosed by curved comb of blunt short setae. Abdomen: With 5 ventrites in males and females, vestiture a discontinuous layer of appressed scales and scattered decumbent setae, integument visible among scales and setae; ventrites 1 and 2 convex at middle in females; in males, ventrite 1 concave at middle, ventrite 2 nearly flat or with slight concavity. Genitalia: Females ( Figs. 3 , 29 ): Tergum VIII broadly convex dorsally, somewhat conical in shape, narrowing toward rounded apex; sternum VIII (spiculum ventrale) with apical expansion broadly spade-shaped, convex ventrally, rounded at apices, cleft medially in apical portion, with fine setae apically; coxites 1 and 2 narrowly angular in dorsal and ventral views, rounded toward apex in lateral view; styli with 2 or 3 primary setae at apex; vagina slightly longer than coxites, membranous, without sclerotized structures therein; spermatheca sickle-shaped, tubular in crosssection, very thin. Males ( Fig. 54 ): Aedeagus with median lobe gently decurved, concave ventrally, apex broadly rounded in dorsal and ventral views, manubrium of tegmen slightly longer than median lobe; median struts of aedeagus 1.6X length of median lobe, internal sac membranous, with 10–12 sclerotized denticles visible in apical portion (anterior portion in inverted sac).

Life History. Adults have been collected in the months of May, June, July, August, and September.

Plant Associations. The type series was collected by sifting old leaves in September ( Schaeffer 1908). One specimen from the Mt. Mitchell area of North Carolina was taken from Prunus sp. (CWOB), and four others were reported from litter under Rhododendron L. ( Ericaceae ) (CWOB).

Geographical Distribution. This species occurs in the southern Appalachian region of eastern North America, in the western parts of North

Carolina and South Carolina (record from Ciegler 2010) at elevations between 1,220 and 1,980 m ( Map 3 ). It also occurs in Indiana .

Chorological Affinities. The range of this species overlaps the combined ranges of the P. erinaceus-P. impressus species pair.

Material Examined. In addition to the lectotype, 30 specimens were examined. USA: Indiana: Wayne Co., H. Winter (1, USNM) . North Carolina: Jackson Co., Balsam, Yellow Face , 1768 m, 25. VI.1971, W. Rosenberg (3, USNM) ; Blue Ridge Parkway, Yellow Face , 1768 m, 4.VIII.1972, W. Rosenberg collection (1, USNM) ; Blue Ridge Parkway, Yellow Face , 1768 m, 22.VI.1973, Rosenberg collection (2, USNM) ; Yancey Co., Black Mountains, Mt. Mitchell , 12.VI.1927, Quirsfeld (1, USNM) ; Black Mountains, Mt. Mitchell , 17.VI.1927, Quirsfeld (1, USNM) ; Black Mountains, Mt. Mitchell (1, USNM) ; Mt. Mitchell , 31.V.1973, W.R. Suter, litter under Rhododendron (4, CWOB) ; Mt. Mitchell , 1220-1830 m, VI.1939, Quirsfeld (1, CNCI) ; Mt. Mitchell, 1520–2040 m, A. Nicolay , 13.VI.1927 (2, USNM; 1, CNCI) ; 15.VI.1927 (2, USNM), (1, CASC) ; 16.VI.1927 (1, USNM) ; Mt. Mitchell , 1980 m, 18.VI.1937, E. Shoemaker (1, USNM) ; 26.VI.1937 (1, USNM) ; Mt. Mitchell , 1980 m, 1.VI.1965, L. & C.W. O’ Brien, Prunus (1, CWOB) ; Mt. Mitchell ,, 12.VI.1973, W.R. Suter, litter at log (3, CWOB) ; Mt. Gibbs , 28.VI.1937, E. Shoemaker (1, USNM) .

Figures

Map 3. Geographical distribution of Panscopus alternatus.

Figs. 1–8. Panscopus species, sternum 8 (spiculum ventrale), ventral (a) and left lateral (b) views. 1) P. maculosus; 2) P. ovatipennis; 3) P. alternatus; 4) P. erinaceus; 5) P. impressus; 6) P. costatus; 7) P. capizzii; 8) P. convergens. Scale bar = 1 mm.

Figs. 27–32. Panscopus species, coxites and vagina, dorsal (a), ventral (b), and left lateral (c) views. 27) P.maculosus; 28) P. ovatipennis; 29) P. alternatus; 30) P. erinaceus; 31) P. impressus; 32) P. costatus. cx = coxites; st = stylus. Scale bar = 1 mm.

Figs. 53–55. Panscopus species, aedeagus, dorsal (a), ventral (b), and left lateral (c) views. 53) P. ovatipennis; 54) P. alternatus; 55) P. impressus. b = belt of tegmen; is = internal sac; mb = manubrium of tegmen; ml = median lobe; ms = median strut; t = tegmen. Scale bar = 1 mm.