Paulo César Motta

Butterflies from the Uberlândia region, Central Brazil: species list and biological comments

A total of 251 butterfly species were recorded in Uberlândia region, with collecting concentrated mainly in forest areas. Aspects of geographic distribution of some Ithomiinae, as well as interactions of both adults and immatures with plants, and reproduction periods for the more abundant species are discussed. Collections in open, riverside, and wetland areas, as well as the use of bait, should substantially increase the number of species.

The silk tuft web decorations of the orb-weaver Gasteracantha cancriformis: testing the prey attraction and the web advertisement hypotheses

Summary Several orb-web spiders build conspicuous decorations in their webs. The prey attraction hypothesis proposes that decorations increase spider foraging success by attracting prey, and that attraction is linked to UV reflectance. Alternatively, the web advertisement hypothesis proposes that decorations are a signal that advertises the presence of the web to large animals. We tested both hypotheses for the web silk tufts of Gasteracantha cancriformis. Even though tufts are UV reflective, we did not find support for the prey attraction hypothesis. In the field, when webs with tufts painted black and control webs were compared, there were no differences in the number of prey captured, number of damaged areas in webs and type of prey captured. In the laboratory, Drosophila melanogaster did not demonstrate preference for tufted silk lines versus non-tufted silk lines. Our data also did not give support for the web advertisement hypothesis. The proportion of web destruction was similar between web with tufts painted black and control webs during four days of experimentation. Therefore, two of the most favoured hypotheses that attempt to explain decorations do not apply for web silk tufts in our study system. Instead we propose that silk tufts might be an aposematic signal.

ECOLOGICAL CORRELATES OF POLYPHENISM AND GREGARIOUS ROOSTING IN THE GRASS YELLOW BUTTERFLY Eurema elathea (PIERIDAE)

Eurema elathea adults were census weekly (1992-1994) in six night-roosts around a forest fragment on a farm, and in two roosts in the urban area of Uberlândia, Minas Gerais, Brazil. Males were grouped in six phenotypic classes. These were based on a range between having a conspicuous wide black bar at the dorsal forewing inner margin (wet season dark morphs) and the absence of that bar (dry season light morphs). The body mass and wing area of co-occurring morphs were compared: differents morphs showed similar means. The abundance of butterflies and morph frequencies varied in close relation to humidity (rainfall). Individuals were infrequent and monomorphically dark in the wet season while light morphs predominated in dry periods when population peaked. A lower fraction of recaptured individuals and higher recruitment were recorded compared to other night-roosting butterflies. Dispersal potential was similar between the sexes and varied seasonally with a more sedentary population in dry periods. The maximum residence time recorded was 91 days for a female and 84 days for a male. The fraction of individuals that moved from one roosting site to another was similar in both sexes and male morphs, but significantly higher on the farm than in the urban area. Also, a significantly higher fraction (21.3%) of marked butterflies was recaptured in the urban area than on the farm (15.6%), suggesting a behavioral modification for sedentariness in the urban individuals. The selective forces shaping a gregarious roosting habit in E. elathea and other butterflies are discussed and a protocooperational strategy for saving energy is proposed.

Cicadas (Hemiptera, Auchenorrhyncha, Cicadidae) from Brasília (Brazil): exuviae of the last instar with key of the species

Eight cicada species were collected in an urban area of Brasilia (Brazil). Their nymphal casts were characterized and a dichotomous key was prepared to identify cicada species.

Redescription of Avicularia taunayi and notes on its habitat and geographical distribution (Araneae: Theraphosidae: Aviculariinae)

We redescribe the poorly known tarantula species Avicularia taunayi (Mello-Leitao, 1920) and present information on its geographical distribution and habits. The spermatheca of the female is unusual for the genus: short, broad, with a median slight curvature and lobes on its basal, median and distal portions. The male resembles other Avicularia species but can be distinguished by the presence of a tibial apophysis on leg I in conjunction with legs I and IV having roughly the same length and the presence of pale rings on the distal femora, tibiae and metatarsi. Additionally, males and females have three pairs of light brown spots extending from the dorsum to the lateral region of the abdomen. Avicularia taunayi is found in the Brazilian Cerrado, a savannah-like biome. It is one of the aviculariine species with the southernmost distribution, reaching as far South as the Tropic of Capricorn.

Three new species of Fufius Simon, 1888 (Araneae, Cyrtaucheniidae) from Brazil with the redescription of Fufius funebris Vellard, 1924 and description of the female of Fufius lucasae Guadanucci & Indicatti, 2004

Abstract The mygalomorph neotropical genus Fufius Simon, 1888 comprises ten species, distributed from Guatemala in Central America to southeastern Brazil, in South America. Most of the species were described from northern South America, in the Amazonian region. Only F. funebris Vellard, 1924 and F. lucasae Guadanucci & Indicatti, 2004 are known from regions more to the south of the continent. Herein we describe three new Brazilian species, Fufius minusculus sp. n. and F. jalapensis sp. n. from the state of Tocantins, and F. candango sp. n. from Distrito Federal. The female of F. lucasae is described for first time and the male and female of F. funebris are redescribed based on specimens collected at the type locality.

A new report of Metacleobis fulvipes (Rower) (Solifugae, Mummuciidae) in central Brazil

The geographic distribution, systematics and general biology of the South American Solifugae are poorly known (Rocha and Cancello, 2002). Knowledge of the order in the Neotropical region is scarce especially in Brazil, which includes distinctive environments such as Caatinga and Cerrado that occupy a large portion of this country (Xavier and Rocha, 2001). In the last five years only 3 studies have been carried out focusing on Solpugida in Brazil: Xavier and Rocha (2001) described Mummucia mauryi as the first Solifugae from the Caatinga; Martins et al. (2004) reported the occurrence of M. coaraciandu in three cerrado phytophysiognomies; and Rocha and Cancello (2002) recently redescribed Metacleobis fulvipes (Rower, 1934) and reported new records for this species: in the Serra da Mesa (Goiás State) and in the Chapada dos Guimarães (Mato Grosso State), both in the Central Brazil cerrado. According to Rocha and Cancello (2002) this species exhibited a diurnal activity, walking and burrowing, and during the night remains inactive under pieces of wood. This study reports a new occurrence of Metacleobis fulvipes in the cerrado of Central Brazil, which amplifies the distribution of this species and also reinforces the necessity for more studies of arachnofauna in the cerrado. During the period of August and September/2004, in a region of Brasilia called São Sebastião, seven live specimens of M. fulvipes were collected using pitfall traps. Ten grids were set in three lines of six pitfalls traps. Each was put in three different cerrado phytophysiognomies: “cerradão”, “cerrado Sensu strictu” and “campo sujo”. Only in the grids localized in the “campo sujo” the presence of M. fulvipes were observed (GRID 1, 15° 57’ 57.7” S and 47° 49’ 41.4” W, Altitude 1133 m; GRID 2, 15° 58’ 09.8” S, 47° 49’ 43.6” W Altitude 1137 m). The animals were fixed in ethanol 80% and deposited in the Laboratório de Aracnídeos at Brasilia University and in the Museum de Zoologia at São Paulo University. The specimens were identified by Dr. Ricardo Pinto-daRocha and are characterized by a brown chelicerae and three longitudinal pale brown stripes on the ectal face joined dorsally above the fondal teeth (Rocha and Cancello, 2002). The area of São Sebastião, a cerrado area which has been rapidly transformed into residential areas, is a grassland landscape characterized by an open area with sandy soil, Vellozia flavicans (Velloziaceae) and termites. The specimens were found only at this time in the area, and no other was found in any locality of Brasilia, but some more collections are necessary.