Galling Insects on Neotropical Species of Baccharis (Asteraceae) G
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This article was downloaded by: [University of Sydney] On: 26 August 2013, At: 13:01 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Tropical Zoology Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/ttzo20 Galling insects on neotropical species of Baccharis (Asteraceae) G. W. Fernandes a , M. A.A. Carneiro a , A. C.F. Lara a , L. R. Allain a , G. I. Andrade a , G. R. Julião a , T. R. Reis a & I. M. Silva a a Ecologia Evolutiva de Herbivoros Tropicais/DBG, CP 486, ICB/Universidade Federal de Minas Gerais, 30161-970, Belo Horizonte, MG, Brazil Published online: 01 Aug 2012. To cite this article: G. W. Fernandes , M. A.A. Carneiro , A. C.F. Lara , L. R. Allain , G. I. Andrade , G. R. Julio , T. R. Reis & I. M. Silva (1996) Galling insects on neotropical species of Baccharis (Asteraceae), Tropical Zoology, 9:2, 315-332, DOI: 10.1080/03946975.1996.10539315 To link to this article: http://dx.doi.org/10.1080/03946975.1996.10539315 PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions Downloaded by [University of Sydney] at 13:01 26 August 2013 Tropical Zoology 9: 315-332, 1996 Galling insects on neotropical species of Baccharis (Asteraceae) G.W. FERNANDES, M.A.A. CARNEIRO, A.C.F. LARA, L.R. ALLAIN, G.I. ANDRADE, G.R. JuuA.o, T.R. REis and I.M. SILVA Ecologia Evolutiva de Herbivoros Tropicais/DBG, CP 486, ICB/Universidade Federal de Minas Gerais, 30161-970 Belo Horizonte, MG, Brazil Received 29 April 1994, accepted 3 October 1995 We report on the insect galls on neotropical species of Baccharis (Asteraceae) and describe new kinds oi galls on Baccharis spp. of the cerrado and rupestrian fields of Brazil. Gall collections were made in several localities in Minas Gerais (Belo Hori zonte, Caratinga; Lagoa Santa, Moeda, Ouro Preto, and Serra do Cip6). Baccharis may support the richest galling fauna of the neotropics (121 galling species on only 40 species of Baccharis). Nevertheless, gallers were not evenly distributed across host plant species. Four species of Baccharis alone supported 46% of the galling fauna. The most diverse fauna occurred on B. dracunculifolia (17 galls), B. concinna (15 galls), B. salicifolia (13 galls) and Baccharis sp. 1 (11 galls). The most numerous galling taxa were, in decreasing order, Cecidomyiidae (Diptera), Lepidoptera (several Gelechiidae), Psyl lidae (Homoptera), and Tephritidae (Diptera). The most diverse gall communities were on Baccharil species that inhabit harsh environments, such as B. concinna in the rupestrian fields of Minas Gerais, B. salicifolia in the dry chaco vegetation of Argentina, and B dracunculi/olia and Baccharis sp. 1 of the cerrado of Lagoa Santa in Minas Gerais. KEY WORDS: BacchariJ. insect community, insect galls, neotropics, species richness. Downloaded by [University of Sydney] at 13:01 26 August 2013 Introduction 315 Materials and method~ 316 Results and discussion 317 Acknowledgments 330 References 330 INTRODUCTION Gall-forming insects are very common in all biogeographical regions of the world, except the poles (see MA~I 1964, GAGNE 1989, FERNANDES et al. 1994). They achieve the highest diversity in warm temperate ecosystems; i.e., between 25° and 40° north or south (PRICE et al. 1996). In the Neotropical region, they are most species-rich in 316 G. W. Fernandes et alii the rupestrian fields and in the cerrado (savanna) vegetation of southeastern Brazil (FERNANDES & PRICE 1988, LARA & FERNANDES 1996a). The mechanisms that in fluence this global distributional pattern are still under investigation, but it appears that plant sclerophylly and its related emergent properties have influenced the evolution of galling insects (see FERNANDES & PRICE 1991, 1992; LARA & FERNANDES 1996b; PRICE et al. 1996). Other studies have addressed other hypotheses on the evolution of the galling habit (e.g., CoRNELL 1983, WARING & PRICE 1990, HARTLEY & LAWTON 1992, BLANCHE 1994, see review by PRICE et al. 1987). Studies on insect galls are now very common in ecology. Galls are often conspicuous and easy to find all year round, which limits methodological problems of seasonality and turnover rates characteristic of other insect herbivores (see LARA & FERNANDES 1996b). The majority of galling insects are host-plant and plant-organ specific, and gall morphology is specific to each inducer (FLOATE et al. 1996) making them excellent systems for the estimation of the patterns of abundance and richness (FERNANDES & PRICE 1988, FERNANDES et al. 1994). In addition. galls may be seen as extended phenotypes of their inducers (WEis et al. 1988). Several ecological hypoth eses have been generated from studies of gall communities on many temperate plants [e.g., Salix spp. (PRicE & RmNINEN 1993), Quercus (AsKEW 1980, CoRNELL 1983), Atriplex (HAWKINS 1984), Chrysothamnus (FERNANDES 1992a), and Solidago (GAGNE 1989). Tropical insect galling communities are, however, poorly known and mostly undescribed. We do not know of any community of tropical insect galls that has been studied in as much detail as the ones mentioned above. Neotropical studies on galling insects have been primarily descriptive (e.g., FERNANDES et al. 1988, GAGNE 1994 and references therein), or centred on the natural history of single species (e.g., FER NANDES et al. 1987, FERREIRA et al. 1990). We believe that a better understanding of gall distribution, gall ecology, and insect plant relationships would be achieved if diverse tropical communities were studied in detail over the long-term to enable appropriate comparisons with corresponding temperate systems. For this reason we have chosen to study the highly diverse insect gall community on the neotropical species of Baccharis Linnaeus (Asteraceae). In this study we present a list, partially extracted from the literature, of the insect galls on neotropical species of Baccharis and report for the first time new types of insect galls found on several species of Baccharis of the cerrado and rupestrian fields of Brazil. Downloaded by [University of Sydney] at 13:01 26 August 2013 MATERIALS AND METHODS This paper is a combination of data extracted from the literature and data obtained by us during a 4 year study. Insect galls on B. concinna Barroso, B. dracunculifolia D.C., and on Baccharis sp. 2 to sp. 9 were collected from 1990 to 1993 by our research group while performing several studies on these plants. On B. concinna and B. dracunculifolia galls were counted on 200 plants twice a year from 1991 to 1993. The other species were surveyed once a year from 1990 to 1993. Surveys were performed in several localities, but primarily in the cerrado and rupestrian fields of the State of Minas Gerais (Belo Horizonte, Lagoa Santa, Maeda, Ouro Preto, and Serra do Cip6), and in the Atlantic rain forest (Caratinga) in southeastern Brazil. Baccharis sp. 2 was sampled in Belo Horizonte, while Baccharis Galling insects on Baccharis 317 sp. 3 to Baccharis sp. 9 were sampled from Lagoa Santa to Serra do Cip6 (between 19°10' and 19°40'S. and 43°30' and 43°55'W). Gall collection methods are reported in FERNANDES et al. (1988). Complementary bibliographical surveys utilized several compendiums and lists of galls on neotropical species of Baccharis as sources of additional information. These are listed in the reference column of Table 1 and additional field site description can be found in these references. Insect galls vary enormously in form, host organ, colour, number of internal larval chambers, and epidermal cover (MANI 1964), and we utilized these variable characters to describe them. Because of the many problems with the taxonomy of tropical insects, we identify most gallers only to family level. Whenever possible, we give the genus and species names. Insects are continuously being reared from galls and these will be identified to the species level in the near future. Some Baccharis were listed as sp. 1., sp. 2, etc. to sp. 9 due to taxonomical problems. The identification of Baccharis at the species level is generally complex due to the large number of species in the genus, approximately 500 (BoLDT 1989). Ninety percent of these species occur in South America (NESOl\1 1990), and more than 120 species are known to occur in southeastern Brasil alone (BARROSO 1976). In addition, hybridization is common in the genus (e.g., FAIN! et al. 1991) making identification complicated. Nevertheless, all plants are being identified by specialists and will be reported in the near future as studies develop. RESULTS AND DISCUSSION Baccharis may have the richest galling fauna of the neotropics. One hundred and twenty one species of galling insects were found on 40 species of Baccharis (Table 1).