Sennius medialis (Sharp, 1885)

Viana, Jéssica Herzog & Ribeiro-Costa, Cibele Stramare, 2013, Review of the largest species group of the New World seed beetle genus Sennius Bridwell (Coleoptera: Chrysomelidae), with host plant associations, Zootaxa 3736 (5), pp. 501-535 : 521-524

Sennius medialis (Sharp, 1885)

( Figs 63–71 )

Bruchus medialis Sharp, 1885: 470 (description, distribution); Pic 1913: 34 (catalog).

Acanthoscelides medialis: Blackwelder 1946: 760 (catalog).

Sennius medialis: Johnson & Kingsolver 1973: 78 (description, key, figures, type designation, taxonomy, distribution, host); Center & Johnson 1973: 670 (biology); Center & Johnson 1974: 1098 (host, guild); Johnson 1977: 123 (host); Johnson 1979: 123 (host); Johnson & Slobodchikoff 1979: 1059 (citation); Johnson & Kingsolver 1981: 419 (list); Udayagiri & Wadhi 1989: 105 (catalog); Luna-Cozar et al. 2002: 26 (list); Turnbow et al. 2003: 276 (list); Kingsolver 2004: 200 (key, diagnosis, figures, host, distribution); Romero-Nápoles & Johnson 2004: 627 (list); Johnson & Romero 2004: 404 (biology); Lorea-Barocio et al. 2006: 519 (distribution, host).

Bruchus auctus Fall, 1910: 166 (description, key, figures, distribution); Johnson & Kingsolver 1973: 78 (synonym).

Mylabris auctus: Leng 1920: 305 (catalog).

Sennius auctus: Bottimer 1968: 1026 ; Johnson 1968: 1270 (type designation).

Redescription. Dimension. BL: 1.6–2.3 mm; BW: 1.2–1.6 mm.

Integument color. Head black, sometimes with red-orange post-ocular macula, labrum red-orange to brown ( Fig. 65 ); all antennomeres red-orange or 6–11 pale to dark brown ( Figs 64, 65 ). Pronotum and pygidium black ( Figs 63, 66 ); base and apex of elytra dark brown to black, median region of each elytron with red-orange rounded macula generally extending from 1st strial interval to outer margin ( Fig. 63 ), sometimes occupying almost entire elytra. Remainder of thorax black ( Fig. 64 ). Legs red-orange except forecoxa, hind tarsus and base of hind femur, dark brown to black ( Fig. 64 ).

Pubescence. Head with white setae on post-ocular lobe and small dense patch posterior to post-ocular lobe, remainder with sparse white setae. Pronotum with white and/or golden setae. Elytra with moderately dense white setae evenly distributed or white and golden setae moderately dense except by white horizontal strip extending from base of 4th to 11th interstices to near de apex of red-orange macula of median region ( Fig. 63 ). Pygidium and ventral surface with moderately dense white setae, denser on posterior margin of metepisternum and basal region of pygidium ( Figs 64, 66 ).

Head with frons convex, frontal carina present and ocular sinus deep, more than half length of eye ( Fig. 65 ). Antennomeres 1 and 3 filiform, 2 and 4 moniliform, 5–10 wider than long, 11 globular but pointed apically. Disc of pronotum strongly sulcate at basal lobe. Elytra with denticles at base of 3rd and 4th strial ( Fig. 67 ). Hind femur on ventral margin with very prominent tooth (0.03–0.08 mm), not microserrate ( Fig. 68 ); hind tibia with lateroventral carina not reaching half its length ( Fig. 69 ).

Male genitalia. Median lobe weakly sclerotized, about 5.5 times longer than wide medially, apex strongly expanded. Ventral valve triangular with truncate apex and lateral margins convex. Internal sac with hinge sclerites long, slightly curved with apex broader; apical region with group of spicules near ventral valve; subapical region with short and slightly dense group of spicules; submedian region without spicules; latero-basal lobes of internal sac with dense and long spicules; basal region with dense spicules throughout ( Fig. 70 ). Tegmen with lateral lobes separated by emargination about 0.7 times their length ( Fig. 71 ).

Material examined. Type (3 Homotypes): Bruchus medialis Sharp, 1885 . In the original description, Sharp studied two males and one female, all distributed in Mexico—Guanajuato (Sallé). They are deposited at the BMNH and it was not possible to examine them. The species was recognized based on Johson & Kingsolver (1973), who revised the species, and the study of the three homotypes deposited in TAMU, with labels: 1, “ 13 mi. N. \ Imuris, Son. \ Mex. VIII-16-65 ”(White) “C. D. Johnson \ Collector”(White) “ Sennius \ medialis \ (Sharp) 19 \ det. C. D. Johnson”(White) “Homotype”(White) “ex. C. D. Johnson Collection \ August 1999, Texas A&M \ University Insect Collection” (TAMU); 1, “ 9 mi. NE Guana- \ juato, Gto., \ Mex. VI-7-68 ”(White) “sweeping \ flowers \ #65- 68” (White) “Taken by \ sweeping”(White) “ Cassia \ tomentosa ”(White) “C. D. Johnson \ collector”(White) “HOMOTYPE \ Bruchus \ medialis Sharp \ det. C. D. Johnson”(Pink) “ex. C. D. Johnson Collection \ August 1999, Texas A&M \ University Insect Collection” (TAMU); 1, “Ariz. 2 mi. SW. \ Patagonia \ Sta. Cruz Co. \ IX-10- 1956 ”(White) “Collectors: L & C. W. O’Brien”(White) “ Sennius auctus \ (Fall) \ similar to type \ 1967 \ det. C. D. Johnson”(Red) “ex. C. D. Johnson Collection \ August 1999, Texas A&M \ University Insect Collection” (TAMU).

Non-type (241): USA: California: East Mojave Scenic Area: 1, VI-18 -[19]93, W. F. Chamberlain (TAMU). Arizona: Altar Valley: 2, XII/1925, L. J. Bottimer (CNCI); 1, 1926, same collector, Cassia leptocarpa (CNCI); 4, 20 /XII/1925, same collector and host plant (CNCI); 2, Baboquivari Mountains: 29/IV/1935, F. H. Parker (FSCA); 1, 12 /V/[19]25, L. J. Bottimer, Cassia leptocarpa (CNCI); 2, 12 /V/1925, same collector and host plant (TAMU); 2, 7 /II/[19]25, same collector and host plant (TAMU); 3, VI/1925, same collector and host plant (CNCI); 2, 27 /V/ [19]25, same collector and host plant (CNCI); 5, 12 /V/[19]25, same collector and host plant (CNCI). Cochise : 2, Carr Cyn. Huach. Mts, 2/VIII /[19]72, C. D. Johnson (TAMU); 4, Just E. of Coronado Nat. Monument, 10/VIII/ 1976, G. H. Nelson, Cassia sp. (FSCA); 2, Ft. Huachuca, 27/IX/1968, Dwight Schuh (TAMU); 9, Carr Cyn Huachuca Mts., 9/X /[19]71, C. D. Johnson, Cassia leptocarpa (TAMU); 4, Huachuca Mts., 8/VI /[19]25, L. J. Bottimer, Cassia leptocarpa (CNCI); 5, same locality , 21/VI /[19]25, same collector and host plant (CNCI); 2, same locality , 2/VII /[19]25, same collector and host plant (CNCI); 6, Huachuca Mts. Ramsey Canyon, 5/X/1956, same collector and host plant (TAMU); 5, same locality , 3/X /[19]56, same collector and host plant (CNCI); 3, same locality , 4/X /[19]56, same collector and host plant (CNCI); 8, same locality , 10/X /[19]56, same collector and host plant (2, USNM; 6, CNCI); 5, same locality , 11/X /[19]56, same collector and host plant (3, CNCI; 2, TAMU); 10, same locality , 14/X /[19]56, same collector and host plant (9, CNCI; 1, TAMU); 3, same locality , 16/X /[19]56, same collector and host plant (CNCI); 1, same locality , 23/X /[19]56, same collector and host plant (CNCI); 4, Huachuca Mts. Carr Canyon, 5/X/1956, same collector and host plant (CNCI); 7, same locality , 11/X/1956, same collector and host plant (5, CNCI; 2, TAMU); 1, same locality , Nov/1956, same collector and host plant (CNCI); 2, same locality, 1956 , same collector and host plant (TAMU); 1, Montezuma Pass, 10/X/1956, same collector and host plant (USNM); 1, XI/1956, same collector and host plant (CNCI); 3, X/1956, same collector and host plant (1, CNCI; 2, TAMU); 3, 4 /X/1956, same collector and host plant (1, TAMU; 2, CNCI); 1, 19 /X/1956, same collector and host plant (TAMU); 1, XII/1956, same collector and host plant (TAMU); 1, 22 /X/1956, same collector and host plant (TAMU); 1, 16 /X/1956, same collector and host plant (TAMU); Douglas: 1, 23 /VIII/[19]26 (CNCI). Sta. Cruz: 6, Hidden Sprs. Valley 9 mi. E. Sonoita, VII/[19]64, R. F. Sternitzky(5 CNCI; 1, TAMU); 1, Pens Blanca Pajarito Mts., 9/VIII/1961, R. H. Arnett Jr. & E. VanTassell (FSCA); 12, 8 mi. W. Wash. Camp, 19/VIII /[19]67, C. D. Johnson, Cassia leptocarpa (TAMU). Nogales: 1, 10 /IX/1906, Koebele (TAMU). Pima : 3, 3 mi. E. Florida Work Cent., 25/VIII/1994, R. Turnbow (FSCA); 1, Portal Southwestern Research Station, 26/VII/1961, L. J. Bottimer (CNCI); 2, Rincon Mts., 27/V/1928, A. A. Nichol (CNCI). Sta Rita mts: 1, 10 /VII/[19]30, E. D. Ball (USNM); 1, 16 /VIII/[19]40, Van Dyle (TAMU); 2, 13 /XII/1925, L. J. Bottimer, Cassia leptocarpa (CNCI); 1, 18 /I/ 1926, same collector and host plant (CNCI); 1, 24 /XI/1925, same collector and host plant (CNCI). Sierra Vista: 9, Huachuca Mts., III/1965, R. F. Sternitzky (CNCI); 1, same locality , V/1965, same collector (CNCI); 2, same locality , IV/1965, same collector (CNCI); 1, same locality , 1–15/VI/1965, same collector (CNCI). Sierrita Mts.: 2, 11 /VI/1925, L. J. Bottimer, Cassia leptocarpa (CNCI). Superstition Mts.: 1, 26 /IX/1925, same collector (CNCI); New Mexico: Grant: 1, 12 mi. E. Central, 19/VIII/1980, T. P. & T. A. Friedlander & P. W. Kovarik (TAMU). Otero: 2, 14 mi. SW Alamogordo, 25/IV/1998, E. G. Rilley (TAMU). Deming: 1, Rock Hound State Park, 7/V / [19]97, W. F. Chamberlain (TAMU). Guadalupe: 3, Santa Rosa State Park, 18/VI/1999, G. M. Chamberlain (TAMU). Texas: Brewster: 9, Heath Canyon Ranch, 3/VII/1999, E. G. Riley (TAMU). Duval: 4, 8.5 mi. NW San Diego, 18/IX/1993, E. G. Riley (TAMU). Eddy: 3, Dark Cyn Rd 5 m W Hwy 62, 26 /IX/1997 Wappers & Huether (TAMU). Edwards: 2, 18 mi. N Carta Vale on Hwy. 377, 30 /VIII/1986 Haack & Kovarick (TAMU). Hidalgo: 2, Bentsen-Rio Grande Valley St. Pk., 9/X/1994, E. G. Riley (TAMU). Jeff Davis: 1, Point of Rocks Rest Stop., 10/ VIII/1992, W. Godwin & E. Riley (TAMU). Valverde: 4, Seminole Canyon St. Pk. Rio Grande Trall, 20/VII/1986, Woolley & Zolnerowich (TAMU); 2, 39 mi. NNW Comstock (Texas road 1024), 12/V/1997, Gillogly & Schaffner (TAMU); 2, Virgil Crossing Devils Riv. nr., 4-29/6/1997, E. G. Riley (TAMU). San Antonio: 1, 8 miles east of San Antonio, 25/V /[19]97, W. F. Chamberlain (TAMU). South Carolina: Columbia : 1, 20 miles west of Columbia , 7/ V/1997, W. F. Chamberlain (TAMU). MEX: No locality : 1, 6 /I/[19]68, I. F. Schaen, Cassia sp. (USNM). Nuevo Leon: La Ascension: 3, 2 miles north of La Ascension, 24/VII/1976, Peigler Gruetzmacher R & M Murray Schaffner (TAMU). Zacatecas: Fresnillo : 3, 15 mi N. E. Fresnillo , 8& 9/VII /[19]64 (1, FSCA; 2, CNCI). Jalisco: Chapala: 6, 16 /VIII/[19]49, L. J. Bottimer (CNCI). Guanajuato: Sonora: 1, 7 m SE Alamos, 27/XI/1970, K. Stephan (FSCA). Guanajuato: 8, 9 mi. NE Guanajuato, 7/VI /[19]68, C. D. Johnson, Cassia tomentosa (TAMU). Michoacán: Pataquero: 4, VIII/1938, L. J. Lipovsky (TAMU). Patzcuaro: 3, IX/1949, L. J. Bottimer, Cassia occidentalis (CNCI). Morelos: Cuernavaca : 2, III/1945, N. L. H. Krauss (USNM). Queretaro: Queretaro: 3, 29 / VII/[19]63, L. J. Bottimer (2, CNCI; 1, TAMU). HON: Olancho: 1, Km. NE. Teg. Candelera, 21/XI /[19]86, R Fisher, Cassia sp., 1 (FSCA).

Distribution. US (Santa Cruz, California, Arizona, New Mexico, Texas, South Carolina), MEX (Sonora, Nuevo Leon, Zacatecas, Jalisco, Guanajuato, Michoacan, Morelos, Queretaro, Colima, Mexico State, Puebla) GUA, HON (Olancho).

Host Plant. FABACEAE : Caesalpinioideae : Senna hirsuta (syn for Cassia leptocarpa ), S. occidentalis , S. bauhinioides Gray, S. multiglandulosa (Jacq.) Irwin & Barneby (syn for Cassia tomentosa ), S. obtusifolia .

Diagnosis. Sennius medialis (subgroup 2) resembles externally S. abbreviatus (subgroup 1) and S. durangensis (subgroup 2). The similarities and differences between these species are mentioned under the "Diagnosis" of the respective species. The male genitalia of S. medialis and Sennius flinte sp. nov. are similar, corresponding to weakly sclerotized versions of the pattern found in the S. abbreviatus group. For this reason these two species are placed in subgroup 2. However, they are easily distinguished by their external morphology, mainly by the integument color of the elytra (black, each with macula, in S. medialis and red-orange in Sennius flinte sp. nov.).

Figures

FIGURES 63 – 71. Sennius medialis. 63, dorsal view; 64, lateral view; 65, head, frontal view; 66, pygidium; 67, base of elytra strial; 68, part of hind leg, internal view; 69, hind tibia, external view; 70, 71 male genitalia: 70, median lobe with hinge sclerites, others sclerites magnified and latero-basal lobes of internal sac; 71, tegmen.