Lissorhoptrus robbinsorum, O'Brien, 2014

O'Brien, Charles W. & Haseeb, Muhammad, 2014, Revision of the “ Rice Water Weevil ” Genus Lissorhoptrus LeConte (Coleoptera: Curculionidae) in North America North of Mexico, The Coleopterists Bulletin 68 (2), pp. 163-186 : 177-178

Lissorhoptrus robbinsorum O’ Brien, new species ( Figs. 17, 18 , 27 , 34 )

Description. Body medium-sized; moderately robust.

Holotype Male. Rostrum: Moderately long, 0.67X as long as prothorax; reddish black, broadly subcylindrical; dorsum weakly curved, apex abruptly depressed; flattened along midline; venter straight, lacking carina; basal 2/3 with contiguous, moderately rough, agglutinate scales; apical 1/3 clothed with subcontiguous, rough, plumose scales; sides parallel; suprascrobal groove weakly developed. Head: Weakly convex; scales subgranulate, contiguous, brownish; plumose scales brown to grayish, on articulating area and around and behind eyes; frons lacking evident setae, broad, 0.65X as wide as head across eyes, flattened, indistinctly set off from rostrum by shallow impression. Antennae: Inserted just in front of apical 1/3; scape moderately short, moderately stout, clavate, with numerous setae; scape and funicle reddish brown; funicle short, 0.80X as long as scape, club elongate-oval, moderately asymmetrical, 0.75X as long as funicle, reddish black, 1 st club segment ca. 0.50X total club length, glabrous. Pronotum: Transverse, 0.90X as long as broad; sides subparallel, weakly expanding from base; apical constriction moderately strong, in apical 1/10; scales dense, roughened, agglutinate; apical constriction dorsally distinct and uniform, strongly rounded behind constriction, sides not impressed behind round area; disc transversely unevenly convex, not undulate, rugulose; medial 1/2 dark brown, sides of disc pale brown; pleuron with dark brown longitudinal vitta; ocular lobes strongly developed. Elytra: 1.44X wider at humeri than pronotum; 1.28X longer than wide at humeri; subparallel, sinuate behind humeri to declivity, declivity at 60° (in relation to dorsal plane); markedly wider than prothorax; apices subacuminate, conjointly slightly emarginate; humeri well-developed, obliquely angulate, subacutely produced; intervals transversely undulate, uneven in width, unevenly convex, odd-numbered intervals with setae inconspicuous; setae subrecumbent, curled, coarse, associated with slight swelling; swellings becoming progressively larger and more acute posteriorly; strial grooves distinct, deep, moderately narrow, punctures medium-sized, round, broad, deep and separated by own diameter, wider than strial grooves; scales subgranulate, contiguous and few imbricate, round and oval, arranged irregularly, usually with 3 or more scales across intervals brown, whitish and black; fasciate; mottled with median area of disc dark brown to black, laterally with whitish to tan longitudinal fascia; cuticle reddish brown to black. Venter: Prosternum medially clothed narrowly between and in front of coxae and broadly behind coxae, with plumose scales. Abdominal ventrites: Ventrite I with deep, broad, median impression, impression very slightly narrowed apically, impression weakly continued on ventrite II, apical margin declivous lateral to impression, 1.67X as long as II; ventrite II weakly convex, apical 1/2 declivous, not impressed on declivity; 2.00X as long as III and IV together; ventrite V transversely convex basally, transversely impressed apically, impression moderately shallow, broad, lacking median subapical carina or tubercle; lacking apicolateral setae; 2.50X as long as III and IV together; 1.25X as long as II; 0.75X as long as I; I and II completely clothed, with contiguous, agglutinate scales; III and IV completely clothed, with dense, suberect, plumose scales, and lacking evident setae; V with basal 1/2 clothed with contiguous, agglutinate scales and apical 1/2 clothed with dense, recumbent, plumose scales. Tergite VII: Apical margin nearly straight, not medially emarginate. Legs: Moderately short; femora clavate, reddish brown; tibiae moderately stout, reddish brown; fore and hind tibiae with inner margin bisinuate, outer margin straight or nearly so toward apex (in lateral view), several moderately short bristles on inner surface, short inconspicuous bristles on outer surface; middle tibiae with long, fine swimming hairs on inner and outer margins; hind tibial mucro 3-toothed, basal tooth large, posteriorly directed, external apical tooth long, slender curved and acute, internal apical tooth small, triangular, and acute; tarsi moderately long, sublinear, reddish brown, slightly widened toward apex; tarsomere 3 not wider at apex than 2, sublinear, subtruncate; claws yellowish. Genitalia: As in Fig. 34 . Standard length: 2.80 mm.

Female. Elytra: 1.44X wider at humeri than pronotum; 1.50X longer than wide at humeri. Tergite VII: Apical margin moderately deeply emarginate medially. Abdominal ventrites: Ventrite I flattened, lacking median impression, 1.53X as long as II; II flattened; not impressed on declivity, apically declivous; ventrite V in basal 2/3 strongly convex, apical 1/3 transversely impressed, impression shallow, broad, lacking median subapical carina or tubercle. Standard length: 2.80 mm.

Intraspecific Variation. This species is relatively uniform except in the color of the body. This ranges from the typical dark brown to black, broad prothoracic vitta, and the large similarly colored macula in front of the declivity. Some individuals have a predominantly brown color with a narrow, incomplete prothoracic vitta not reaching the apical margin, and scattered dark brown to black small maculae. The range in length is 2.50–3.00 mm.

Etymology. This species is named in honor of Mr. Peter Robbins and his daughter Alicia, for invaluable support with access to and lodging on the Little Outfit Ranch, San Rafael Valley, Santa Cruz County, AZ, where much of the type series was collected.

Remarks and Comparative Notes. This species is somewhat similar to L. oryzophilus , but the latter has a longer rostrum, ca. 0.75–0.67X as long as the prothorax, has broad or flatter elytral intervals and possesses three or more rows of scales across these intervals. In some cases, it is necessary to compare the differences in the hind tibial mucro of the male and/or the apex of tergite VII of the female.

Biological Notes. Adult specimens were collected in large numbers from an aquatic grass, E. crus-galli , and their feeding was observed on these plants. The same is true of a second grass species, Echinochloa holciformis . Adults feed in straight, vertical lines through the upper or lower epidermis, leaving pale tan scars formed from the epidermal surface not eaten, approximately 1 mm wide and 6–12 mm long. Pupal cells were found in numbers attached to the roots of both species of plants pulled from the mud and washed to expose the cells. Some of these were opened and live pupae, larvae, and mature adults were collected.

Type Locality. USA, Arizona, Santa Cruz County, 2 miles south of Canelo Pass, San Rafael Valley , FR 799, N31°28′48″ W110°34′09″, 1,553 m .

Distribution. Known only from three sites in the San Rafael Valley in southeastern Arizona.

Type Material. H o l o t y p e, a l l o t y p e, a n d 163 paratypes from: USA: AZ: Santa Cruz County, 2 mi. S. Canelo Pass, IX-19-2005, C.W. O’ Brien (2); 21-VI-2006, C.W.O’ Brien, submersing cow dung in water (4), cooked debris and dry cow dung (1); 25-VI-2006, C.W. & L.B. O’ Brien, under cow dung windrows by pond (holotype, allotype, and 23); 29-VI-2006, C.W. & L.B. O’ Brien, submersing dry bear dung in water (5); XI-23-2006, C.W.O’ Brien, under stones and dung (2); 14 March 2008, C.W.O’ Brien, ex dry Marsilea mollis Robinson & Fernald (3); VII-15- 2010, under dry cow dung (3); 9-21-2011, on Echinochloa holciformis (1); Sept. 27 2008 C.W. O’ Brien Beating Echinochloa Crusgalli (18), ex pupal cell on roots Echinochloa Crusgalli (1); X-4-2008, C.W.O’ Brien, beating Echinochloa Crusgalli (10), Treading Echinochloa Crusgalli (5); X-5-2008, C.W.O’ Brien, beating Echinochloa holciformis (14); 17 October 2008 C.W.O’ Brien, beating Echinochloa Crusgalli over Marsilea (3); 16-X-1910, C.W.O’ Brien (8), on Echinochloa Crusgalli (7), eating aquatic grass and Cyperaceae (1); IV-30-2011, C.W.O’ Brien, ex dry cow dung (2); Aug.-7-2013, C.W.O’ Brien ex dry cow dung submersed in H 2 O (8), Aug.-11-2013 (26); Little Outfit Ranch, 9-26-2008, C.W.O’ Brien, swept Echinochloa holciformis around shore of pond (1), swept shore around pond (1); X-4-2008, C.W. O’ Brien, beating Echinochloa holciformis (7), X-5-2008, Beating Echinochloa holciformis (4); III-31-2009, C.W.O’ Brien under stone pond shore (1); 8-17-2009, at pond C.W. & L.B.O’ Brien (1); X-16-2010, C.W.O’ Brien, at pond (1).

The holotype and allotype are in CWOB on long term loan from CASC. Also, paratypes are in ASUT, BMNH, CASC, CDFA, CMNC, CWOB, FAMU, FSCA, NMHN, NHRS, NZAC, TAMU, UAIC, UNAM , and USNM.

Figures

Figs. 9–18. Lissorhoptrus species, habitus, dorsal and lateral views. 9, 10) L. lacustris; 11, 12) L. buchanani;

Figs. 19–30. Lissorhoptrus species. 19–27: Male hind tibial mucro (internal lateral view). 19) L. simplex; 20) L. oryzophilus; 21) L. lacustris; 22) L. longipennis; 23) L. longitarsus; 24) L. buchanani; 25) L. chapini; 26) L. insularis; 27) L. robbinsorum. 28) L. oryzophilus, female hind tibial mucro. 29–30: Apical margin of female seventh tergite. 29) L. oryzophilus, a = deep emargination, b = extruded ovipositor; 30) L. simplex, c = shallow emargination.

Figs. 31–34. Lissorhoptrus species, male median lobe, dorsal view. 31) L. simplex; 32) L. oryzophilus; 33) L. lacustris; 34) L. robbinsorum.