Rhopalotria (Rhopalotria) slossoni (Schaeffer, 1905)

O’Brien, Charles W. & Tang, William, 2015, Revision of the New World cycad weevils of the subtribe Allocorynina, with description of two new genera and three new subgenera (Coleoptera: Belidae: Oxycoryninae), Zootaxa 3970 (1), pp. 1-87 : 25-26

Rhopalotria (Rhopalotria) slossoni (Schaeffer, 1905)

Figures: habitus: 25–28, 274; antennal pockets: 107; male genitalia: 137–138, 179, 201, 219, 237; female genitalia: 246.

(Adult male and female, larva, pupa and egg illustrated in Norstog et al. 1992, Norstog and Nicholls 1997)

Allocorynus slossoni Schaeffer, 1905:139

REDESCRIPTION—Body minute to small (range 1.8–3.1 mm, mean = 2.6 mm, n = 38), robust, broad-oval; distinctly bicolored, orange-red and black.

Male. Rostrum: moderately long, as long as pronotum, brownish orange; coarsely, rugosely punctate in basal 2/3, finely more sparsely punctate in apical 1/3, moderately strongly expanded in apical 1/4; moderately but evenly curved in lateral view. Head: entire dorsum including forehead, rugosely punctate, forehead nearly equal in width between median basal and apical margins of eyes. Antennae: scape as long as desmomeres 3+4, 1–2 elongate, 3–7 rounded, submoniliform; scape and funicle reddish brown; club with rhopalomeres 1 and 2 piceus to black, apical rhopalomere pale yellowish. Prothorax: strongly transverse, 1.33 X wider than long; apex moderately narrow, evenly expanded to middle, there subparallel to slightly rounded base; lateral margins with minute denticles; disc with coarse, dense, not contiguous punctures, laterally subrugose; individuals with pronotum, dorsal surface of head and profemora with fine reticulation visible under high magnification 40–100X; uniform orange-brown. Scutellum: narrowly subquadrate, with sparse large coarse punctures. Elytra: 0.68–0.71 X as wide as long; subparallel behind rounded humeri, to slightly expanded near declivity, there suddenly evenly narrowed to broadly rounded deeply emarginate apices; unevenly coarsely punctured, humeral area with discrete punctures, medially and apically transversely rugosely punctured; humeral and posthumeral areas and submedially orange-brown, remainder including postscutellar sutural area black. Legs: very robust, procoxae protruding, with pair of blunt inner apical processes; profemora very strongly asymmetrically swollen, with apical pit-like impression, receiving base of tibia, each margin with small apical tooth; protibiae very stout in lateral view, with base very strongly rounded with right angle bend, large tooth on anterior inner surface near base, inner surface weakly submedially narrowly excavate from base to near apex, apex with large anterior mucro, and rather large posteriorly directed tooth. Length, pronotum and elytron: 3.20 mm.

Female. Same as male except: Rostrum: 1.3 X longer than pronotum, smooth, nearly impunctate, very weakly expanded apically. Prothorax: 1.50 X wider than long; sides more or less evenly rounded from narrow apex to slightly narrowed base. Legs: protibiae lacking inner basal tooth, inner surface with moderately broad shallow excavation; with two apical teeth, small and subequal in size. Length, pronotum and elytron: 2.80 mm.

Genitalia and Associated Structures— Male. Length of penis and apodemes together 0.71–0.84 mm (n = 3). Penis: in dorsal view subparallel to slightly tapering, near gonopore tapering increasing sharply, but evenly, apex appearing rounded (Figs. 137, 179). Internal sac: in fully extruded position demarcated by pair of sclerotized dorsally pointing transfer apparatus into two portions (Fig. 237), anterior 2/3 near apex of penis covered with spicules, posterior 1/3 without spicules; short filament arising subapically from between transfer apparatus. Tegmen: apical visor medium-length, <1/3 its width; distal margin with 14–18 setae (Figs. 201–202, 219, visible number in 2 photos examined). Female. Sternite VIII: 0.69–0.70 mm long (n = 2), arms slightly shorter than apodeme, diverging from apodeme with slight angle (<20˚) between arms for ~ 3/10 of length, then diverging at moderate angle (~ 45˚) for ~ 3/10 of length, then curved inward and briefly subparallel, and converging slightly near apices (Fig. 246).

Intraspecific Variation— The rostral length relative to the pronotal length of males 1.05–1.20 (mean = 1.10, n = 10) and of females 1.22–1.37 (mean = 1.30, n = 10); the pronotal width relative to the pronotal length of males 1.36–1.48 (mean = 1.42, n = 10) and of females 1.49–1.61 (mean = 1.55, n = 10).

Remarks— Rhopalotria slossoni is most closely related to R. dimidiata and is distinguished by its black elytra with brown only in the humeral region and its more highly fused sensory pockets of rhopalomeres 1 and 2 of the club (Figs. 106–107).

Biology— Occurs naturally on the native Zamia from southern Florida; different workers agree that the host Zamia in this area forms a single species, but different names have been assigned to it including Z. floridana and Z. pumila ; currently it is recognized in the World List of Cycads ( Osborne et al. 2012) as Z. integrifolia . Observation and exclusion experiments by Tang (1987) and Norstog et al. (1992) demonstrated that R. slossoni is a pollinator of Z. integrifolia in Florida.

Range— Native to southern Florida; collected on the east coast from Palm Beach Co. to Miami-Dade Co. and on the west coast from Sarasota Co. Although suitable host Zamia sp. occur naturally through most of northern Florida into southern coastal Georgia it has not been detected from this region until recent collections in Orlando, Orange Co, Florida (S. Kelly, pers. comm). This may be a recent introduction via the landscape industry.

Material Examined— U.S.A.: Florida: [Miami-Dade Co.], Homestead, ex Zamia flowers, 28-II-19, Schwarz & Barber (1); 13-III-19, Schwarz & Barber (1), ex Zamia , 26-II-19, E.A. Schwarz (2); Homestead Ag. Res. & Ed. Center, XII-1-1972, R.M. Baranowski, ex strobilus Zamia integrifolia (502); Homestead, I-1997, R. M. Baranowski, on Zamia floridana ♂ flowers (134); Miami Springs, ex cone ♂ Zamia integrifolia , 9-I-2008, W. Tang (13); Navy Wells, [GPS coord. omitted], 28-I-2006, W. Tang , wild Zamia floridana M cone (17); Thompson Park, [GPS coord. omitted], 28-XII-2005, W. Tang , ex Zamia floridana M cone (8); Thompson Park, [GPS coord. omitted], 28-I-2006, W. Tang , ex Zamia floridana M cone (55); Orange Co., Orlando, UCF Campus/MacKay Tract, N28°35’21”, W81°12’56”, Sawgrass Marsh-Red Maple, Malaise trap, 2/7/2013, S. McCarthy, S.M. Fullerton (1); UCF Campus—outside Bio. Bldg., N28°36’0”, W81°11’53”, Ex: Male Zamia cones, 2/12/2014, S.L. Kelly (10); Palm Beach Co., Lake Worth, ex ♂ cone Zamia floridana , Jan-2011, D. Holton (9); Palm Beach Co., Loxahatchee, ex ♂ cone Zamia floridana , Feb-2011, D. Holton (3); Sarasota Co,Venice, N27˚ 07.01 W 82˚21.65, 21-I-2006, W. Tang , cult. Zamia floridana M cone (11); Englewood, N26˚60 W82˚23.6, 22-I-2006, W. Tang , cult. Zamia floridana M cone (6); N27˚ 0.2 W 82˚24, 22-I-2006, W. Tang , wild Zamia floridana M cone (7); N27 ˚ 0.1 W 82 ˚ 23.2, 22-I-2006, W. Tang , wild Zamia floridana M cone (1); Venice, LB Pres. [Lemon Bay Preserve], N27 ˚ 02 W82 ˚ 25, 7-II-2006, M. Perry, wild Zamia floridana M cone, (22); Koch Par. [Parcel], N27 ˚ 06 W82 ˚ 20, 7-II-2006, M. Perry, wild Zamia floridana M cone (3); Jelk Pres. [Preserve], N27˚06 W82˚21, 7-II-2006 M. Perry, wild Zamia floridana M cone (1). Holotype not seen. Specimens (807) are deposited at ANIC, ASUT, BMNH, CAS, CMNC, CSCA, CWOB, EMEC, FMNH, FSCA, IADIZA, IEXA, INBio, IZCAS, MIUP, MNHN, STRI, UCFC, UNAM, USNM, ZMHB.