Eleonora Trajano

Ecologia de populações de morcegos cavernícolas em uma região cárstica do sudeste do Brasil

The upper valley of the Rio Ribeira, a carbonatic rock region in the south of the state of Sao Paulo, Brazil, has a great number of caves; the bat community of the area is the subject of the present study. Between October 1978 and October 1980 specimens of five families and 23 species were captured. The species showed an irregular distribution among 32 of 39 caves visited. The community is very diversified, consisting of a specially abundant species (Desmodus rotundus), some very common species (Carollia perspicillata, Artibeus lituratus and Anoura caudifer), and several common and rare species. It differs from other neotropical communities studied in the relatively high frequence of A. caudifer, which probably takes over the ecological role of Glossophaga soricina, and in the great diversity of medium to large sized Phyllostominae. The great diversity and the high relative abundance of some species is probably related to the availability of food afforded by farms and domestic stock N important for the herbivorous and hematophagous species N and to the high number of caves N important mainly for the Phyllostominae and probably for D. rotundus. It is suggested that the structure of a roosts community is primarily determined by the location: the more isolated a cave, the greater and more diversified tends to be its community, regardless of the caveis morphometric characteristies («opportunistic occupation»). Only in densely grouped caves factors such as size would tend to be of some importance. Due to the great number of roosts and the lotv sociability of the bats, the Upper Ribeira populations tend to be distributed all over the available caves, that have small populations (with exception of some relatively isolated ones) varying in density through the year. The occurrence of certain species in individual caves seems to be affected by presence of others in the same roost: A. lituratus, Diphylla ecaudata and Chrotopterus auritus tend to occupy the same caves as D. rotundus, whereas Puripterus horrens and A. caudifer avoid them. Common species showed a «sunset-related» timing of flight activity. The emergence of the majority of the populations begins at dusk, but the activity peak at cave entrance varies in timing and duration. The strictly insectivorous species (Peropterix macrotis, Myotis nigricans and P. horrens and also A. caudifer leave the roost earlier, showing an emergence peak during the crepuscle; for the others, the peak occurs after darkening. A few species, such as D. rotundus and Lonchorhina aurita, emerge only after total darkness. The use of temporary, nocturnal roosts seems to be frequent in the Upper Ribeira, occurring during or after foraging activities; individuals of A. lituratus can use caves as ingesting places. C. perspicillata finishes its feeding activities earlier than the other common species, which indicates a high foraging efficiency. With few exceptions, bats of the Upper Ribeira do not carry their young during foraging. The supply of food for the hematophagous species is represented by small and medium sized domestic animals (poultry and pigs); wild animals may also be significant as prey.

Ecology of subterranean fishes: an overview

A synthesis of ecological data available for subterranean fishes throughout the world is presented, and comparatively analyzed in an evolutionary context. Methods of ecological research are described, and their potential and limitations for the study of hypogean fishes are discussed. Ecology of troglobitic (exclusively subterranean) fishes is discussed with focus on distribution areas, population densities and sizes, use of habitat and movements, life cycle and feeding. When data are available, these species are compared with their epigean relatives. Putative ecological autapomorphies of troglobitic fishes, including habitat change, adaptations to cope with food scarcity, and precocial lifestyles, are interpreted in ecological and evolutionary contexts. Species interactions among subterranean species, including cases of syntopy and predation are briefly analyzed. Non-troglobitic hypogean fishes, with their ecological importance and evolutionary role, are also addressed. Problems of classification of subterranean fishes according to the Schiner-Racovitza system (troglobites, troglophiles and trogloxenes) are discussed, and a scenario of evolution of subterranean populations is presented.

Use of Shelters by the Neotropical River Otter (Lontra longicaudis) in an Atlantic Forest Stream, Southeastern Brazil

Use of shelters by the Neotropical river otter ( Lontra longicaudis ) was studied in a head-water stream of the Atlantic Forest, southeastern Brazil, during 1994. L. longicaudis used almost all types of natural cavities available along river banks, and they excavated burrows or found shelter in dense grass. Two large caves were used as shelters and also to raise young. The degree of conservation of the forest and human disturbance around the shelters did not influence use by otters. However, otters used shelters located higher on the river banks more frequently, probably because they were less vulnerable to flooding. Considering all shelters found during 1 year, shelters of L. longicaudis were distributed at random along the stream, and scent marks were not concentrated around them. Number of shelters in use per month was constant throughout the year, indicating that this can be used to monitor populations of river otters.

Population ecology ofPimelodella kronei, troglobitic catfish from Southeastern Brazil (Siluriformes, Pimelodiae)

SynopsisPimelodella kronei, a cave derivative of the pimelodid catfishP. transitoria, has been found in five caves of the Ribeira River valley, SE Brazil. I investigated the ecology of the most conspicuous population, that from Areias Caves, by capture-mark-recapture. During the two-year study, 170 specimens ofP. kronei were marked, 81 were recaptured at least once, multiple recaptures were frequent. These blind catfishes tended to be recaptured in the same site where they were marked, suggesting a sedentary life and possibly territoriality. The home range was 200 m along the stream, or more where food was scarcer.P. kronei population size in 800 m of permanent stream was 150–200 individuals.P. transitoria also inhabits the cave, at a density ten times lower. The growth rate ofP. kronei was less than 0.1 cm × month−1, and longevity was 10–15 years. These data, and evidences of an infrequent reproduction, indicate a K-selected life cycle, probably as a consequence of food scarcity.

Composição da fauna cavernícola brasileira, com uma análise preliminar da distribuição dos taxons

New data on Brazilian cave fauna are added to previous surveys and the relative abundance and distribution of the cavernicolous taxa is discussed. Terrestrial representatives of several arthropod families and genera are common in both tropical and subtropical Brazilian caves: Endecous and Eidmanacris crickets, Reduviidae heteropterans, Carabidae, Catopinae and Ptilodactylidae beetles, dipterans such as the Chironomidae, Keroplatidae, Phoridae and Drosophilidae, Hydropsychidae trichopterans, Pseudonnanolenidae and Chelodesnidae millipedes, Plato, Ctenus, Loxosceles and Blechroscelis spiders, Pachylinae opilionids, Chernetidae pseudoscorpions and acarians such as the Macrochelidae and Uropodidae. Other taxa are mainly or exclusively tropical Blattelidae, Blattidae and BlaberidaE cockroaches, Histeridae beetles, Noctuoidea moths, social insects as termites and ants, Styloniscidae isopods, Migalomorpha spiders, Amblypigi On the other hand, Psauridae spiders, Goniosoma and Tricommatinae opilionids, Elmidae beetles, and Philosciidae isopods seems to be mainly subtropical. Brazilian aquatic cave fauna seems to be less diversified than the terrestrial one. Siluriform fishes such as pimelodids, trichomycterids and loricariids predominate throughout the country, besides decapod (Macrobrachium shrimps, Potamidae crabs, Aegla anomurans, the latter exclusive of subtropical caves) and amphipod (Spelaeogammarus, in tropical caves, and Hyalella) crustaceans. Insect larvae (e.g. Elmidae coleopterans, Nematocera dipterans, trichopterans) and adults (e.g. Veliidae and Naucoridae heteropterans, Dytiscidae coleopterans), oligochaetes and gastropods such as the Hydrobiidae, are also relatively common. Blechroscelis spiders, Goniosoma opilionids, Zelurus heteropterans, Eidmanacris crickets, Keroplatidae dipterans and Macrobrachium shrimps, among others, live next to the entrance zone in the majority of the caves. But, these animals become troglofiles under certain circunstances (an exceptional input of energy, or the absence of competition with cave-adapted species more efficient).

Cytogenetic analysis of the Brazilian blind catfish Pimelodella kronei and its presumed ancestor, P. transitoria

SUMMARYKaryotypes of the blind catfish Pimelodella kronei from three different caves in the southwestern part of the State of Sao Paulo, Brazil, and of its presumed ancestor Pimelodella transitoria were examined. Chromosome number and formula, as well as C-banding pattern and NOR location were found to be the same in both species, supporting the hypothesis of a close relationship and even conspecificity of P. kronei and P. transitoria.

Locomotor activity pattern of Brazilian cave catfishes under constant darkness (Siluriformes, Pimelodidae)

Abstract Troglobites ‐ cave restricted species ‐ are good models for chronobiological studies focusing on the functions of circadian rhythmicity since they provide a test for hypotheses on external versus internal selection. Cases of reduction in the circadian components of activity have been reported for cave fishes, beetles, and crustaceans, but the methods of data analysis are not fully comparable. We present the results of spectral analysis of locomotor activity in two species of troglobitic catfishes: the less specialized Pimelodella kronei (compared to its eyed close relative, P. transitoria) and a highly specialized Imparfinis, undescribed species. The activity of seven specimens off. transitoria, nine of P. kronei, and six of Imparfinis sp. was automatically recorded in an infra‐red photocell device, for four to ten consecutive days, under constant darkness. All the eyed catfishes showed significant free‐running circadian components, as did seven P. kronei and three Imparfinis specimens. Variable ...

Pimelodella spelaea: A New Cave Catfish from Central Brazil, with Data on Ecology and Evolutionary Considerations (Siluriformes: Heptapteridae)

Abstract Pimelodella spelaea, new species, is described from a subterranean stream tributary to the São Bernardo River inside the São Bernardo Cave, in the São Domingos karst area, upper Tocantins River basin, central Brazil. The new species can be distinguished from its epigean (surface) congeners by derived troglomorphic features such as smaller eyes and fainter coloration, which are nevertheless less reduced than in the other known troglobitic (exclusively subterranean) species, Pimelodella kronei, from southeast Brazil. Ecological data such as habitat characteristics, population data based on mark-recapture techniques, and distributions of frequencies of standard length, weight, and condition factor, were obtained during the dry season of 2000 (May to September). A relatively high population density (about one individual per m−2) was recorded for the accessible habitat, which is probably much lower in the nonaccessible, phreatic area of distribution. The low condition factor recorded for P. spelaea, which tended to decrease along the study period, indicates a regime of severe food limitation, intensifying along the dry season. An allopatric model of differentiation is hypothesized, either because of topographic isolation or because of local extinction of epigean relatives, or both factors combined. The conservation status of the new species is also discussed.

A new species of Glaphyropoma: the first subterranean copionodontine catfish and the first occurrence of opercular odontodes in the subfamily (Siluriformes: Trichomycteridae)

A new species of the rare copionodontine genus Glaphyropoma is described from subterranean waters in the Diamantina Plateau, Bahia State, central northeastern Brazil. This is the first troglomorphic species in the subfamily Copionodontinae. It is distinguished from all other copionodontines by the presence of opercular odontodes, and further distinguished from its only congener, G. rodriguesi, by the reduction of dark integumentary pigmentation. The new species shares the single synapomorphy previously proposed for Glaphyropoma, the marked narrowing of the first hypobranchial and indirect character evidence also supports its inclusion in the genus. The presence of opercular odontodes in the new species, in combination with a reviewed hypothesis of sister group relationship between Copionodontinae and Trichogeninae, indicate that the absence of opercular odontodes in previously-known copionodontines is secondary, rather than primitive.

Ecological Classification of Subterranean Organisms

For 150 years, animals found in subterranean habitats, particularly caves, have been classified into three categories based on their ecological–evolutionary relationships with this environment, according to the Schiner–Racovitza classification: troglobites , troglophiles , and trogloxenes . Overthe last century, some modifications in nomenclature and redefinition of categories, including subdivisions, have been proposed, except for troglobites (exclusively subterranean organisms), which remained stable. Most controversies refer to trogloxenes, whose definition varies considerably among classifications; the main point of disagreement is the inclusion or not of organisms accidentally introduced in caves. New terms have been recently proposed— stygobites , stygophiles , and stygoxenes —to encompass aquatic organisms in nonkarst habitats. A broader classification, with the original three categories (accidentals excluded) redefined in order to incorporate the ecological differences between source and sink populations, is presented.