Sennius trinotaticollis, (PIC)

Pikart, Tiago Georg, Souza, Gabriely Köerich, Viana, Jéssica Herzog, Serrão, José Eduardo & Zanuncio, José Cola, 2011, Sennius trinotaticollis (Pic) (Coleoptera: Chrysomelidae: Bruchinae) in Brazil: New Distribution and Host Records, The Coleopterists Bulletin 65 (4), pp. 377-380 : 378-379

SENNIUS TRINOTATICOLLIS (PIC) ( COLEOPTERA : CHRYSOMELIDAE : BRUCHINAE) IN BRAZIL: NEW DISTRIBUTION AND HOST RECORDS

TIAGO GEORG PIKART, GABRIELY KÖERICH SOUZA Departamento de Biologia Animal, Universidade Federal de Viçosa, 36570-000 Viçosa, Minas Gerais, BRAZIL [e-mail]

JÉSSICA HERZOG VIANA Departamento de Zoologia, Universidade Federal do Paraná, 81531-980 Curitiba, Paraná, BRAZIL

JOSÉ EDUARDO SERRÃO Departamento de Biologia Geral, Universidade Federal de Viçosa, 36570-000 Viçosa, Minas Gerais, BRAZIL

AND

JOSÉ COLA ZANUNCIO Departamento de Biologia Animal , Universidade Federal de Viçosa, 36570-000 Viçosa, Minas Gerais, BRAZIL

Bruchines ( Coleoptera : Chrysomelidae :Bruchinae) are known as seed beetles or bean weevils. Several species of Bruchinae damage seeds of economically important agricultural crops such as Glycine max (L.) (soybean) ( Costa et al. 2007), Phaseolus coccineus L. (runner bean), Phaseolus vulgaris L. (common bean), Phaseolus lunatus L. (lima bean) ( Hansson et al. 2004; Bonet 2008), Vigna radiata L. (mung bean) ( Somta et al. 2008), and Vigna unguiculata (L.) Walp (cowpea) ( Aebi et al. 2008). Damage reduces the quantity and quality of the seeds, making them unsuitable for human consumption and agricultural use ( Somta et al. 2008).

Bruchinae consist of about 1,700 described species distributed in six tribes, nine subtribes, and 67 genera worldwide (Udayagiri and Wadhi 1989; Johnson and Romero 2004; Johnson and Romero 2006). The genus Sennius Bridwell, 1946 encompasses 48 species occurring in the Nearctic and Neotropical regions ( Silva et al. 2003). Most of them feed on seeds of Leguminosae subtribe Cassiinae ( Johnson 1977, 1984), which includes the genera Senna Mill , Chamaecrista Moench , and Cassia L. ( Irwin and Barneby 1981). Although the number of described species of Sennius is relatively high, details about the geographic distribution and hosts of some species occurring in Brazil are scarce. Thus, the aim of this study is to record, for the first time, Sennius trinotaticollis (Pic, 1930) on Senna macranthera (Colladon) Irwin and Barneby and its occurrence in Minas Gerais, Brazil.

Seeds of S. macranthera infested by bruchines were collected in Viçosa (20°46′11″ S, 42°52′31″ W), Minas Gerais in August 2009 and sent to the Laboratório de Sementes Florestais, Universidade Federal de Viçosa, where they were stored in plastic bags in a dark room at 20° C and 60% RH. Bruchines that emerged from the seeds were collected and stored in 70% alcohol and sent to the Laboratório de Sistemática e Bioecologia de Coleoptera of the Universidade Federal do Paraná for identification by the third author. Two bruchine species were identified as Sennius bondari (Pic, 1929) and S. trinotaticollis . Voucher material is deposited in the Coleção de Entomologia Pe. J. S. Moure, Departamento de Zoologia, Universidade Federal do Paraná, Curitiba, Paraná, Brazil.

Sennius species feed mainly on seeds of the genus Senna ( Johnson 1984) . Sennius bondari is a generalist species and has been found damaging seeds of several Senna species (Ribeiro-Costa 1998; Ribeiro- Costa and Reynaud 1998), including S. macranthera ( Linzmeier et al. 2004) . The only known hosts of S. trinotaticollis are Senna hayesiana (Britton and Rose) Irwin and Barneby and Senna oxyphylla (Kunth) Irwin and Barneby in Panama and Guatemala ( Johnson 1977, 1984). Sennius trinotaticollis was just recently found in Brazil (J. H. Viana, unpublished usually with a red-orange transverse band occupying part of its basal third, remainder of elytral integument brown, with a dense strip of white setae in the posterior region of strial intervals 4–9, otherwise with scattered brown setae; pygidium - usually integumental color of the basal half red-orange and brown in apical half, with dense, white hairs in basal region and scattered brown setae.

Senna macranthera is the only known host plant shared by S. bondari and S. trinotaticollis . This plant is widely used for landscaping and in the recovery of degraded areas in Brazil and the occurrence of these seed predators may significantly reduce the plant’ s reproduction in these uses. Control of bruchines includes chemical methods (Sing and Arbogast 2008), host plant resistance (Appleby and Credland 2004) and use of parasitoids as natural enemies ( Pikart et al. 2011). Therefore, further studies on the biology and control methods of S. bondari and S. trinotaticollis are necessary.

data) but without an associated host plant. Thus, specimens obtained in this study have added to our knowledge of the hosts of S. trinotaticollis , and a new country record in Brazil.

Sennius trinotaticollis belongs to the abbreviatus species-group, which also includes Sennius abbreviatus (Say, 1824) , S. bondari , Sennius durangensis Johnson and Kingsolver, 1973 , Sennius lawrencei Johnson, 1977 , Sennius lebasi (Fahraeus, 1839) , Sennius leucostauros Johnson and Kingsolver, 1973 , Sennius medialis (Sharp, 1885) , and Sennius rufomaculatus (Motschulsky, 1874) (Johnson and Kingsolver 1973; Johnson 1977). This group is characterized by the morphology of the male genitalia, i.e. the submedian region of the inner bag with dense lines of spicules generally short and forming a large and dense mass, subapical region usually with two large groups of spicules, and inner bag trilobed with lateral lobes coated with short spicules (Johnson and Kingsolver 1973).

Although belonging to the same group, S. bondari and S. trinotaticollis have external morphologies quite distinct with differences in integumental color and pattern of pubescence. Sennius bondari ( Figs. 1A and B ) has black integument with pubescence arranged as follows: elytra – white, dense pubescence forming a submedial semicircle, remaining pubescence a mix of white, gold, and black setae; pygidium – a dense patch of white setae in the medial-basal region. Sennius trinotaticollis ( Figs. 1C and D ) has: elytra – integumental color

Figures

Fig. 1. Sennius spp. A) Dorsal habitus and B) Pygidium of S. bondari, C) Dorsal habitus and D) Pygidium of S. trinotaticollis. Scale line = 0.5 mm.