Anacondas Research Articles

WHAT IS THE LENGTH OF A SNAKE?

The way that herpetologists have traditionally measuredlive snakes is by stretching them on a ruler andrecording the total length (TL). However, due to the thinconstitution of the snake, the large number of intervertebraljoints, and slim muscular mass of most snakes,it is easier to stretch a snake than it is to stretch anyother vertebrate. The result of this is that the length ofa snake recorded is infl uenced by how much the animalis stretched. Stretching it as much as possible is perhapsa precise way to measure the length of the specimenbut it might not correspond to the actual length ofa live animal. Furthermore, it may seriously injure a livesnake. Another method involves placing the snake in aclear plexiglass box and pressing it with a soft materialsuch as rubber foam against a clear surface. Measuringthe length of the snake may be done by outlining itsbody with a string (Fitch 1987; Frye 1991). However, thismethod is restricted to small animals that can be placedin a box, and in addition, no indications of accuracy of thetechnique are given. Measuring the snakes with a fl exibletape has also been reported (Blouin-Demers 2003)but when dealing with a large animals the way the tapeis positioned can produce great variance on the fi nal outcome.In this contribution we revise alternative ways tomeasuring a snake and propose a method that offers repeatableresults. We further analyze the precision of thismethod by using a sample of measurements taken fromwild populations of green anacondas (Eunectes murinus)with a large range of sizes.

REPRODUCTIVE ECOLOGY OF BOINE SNAKES WITH EMPHASIS ON BRAZILIAN SPECIES AND A COMPARISON TO PYTHONS

Boids occur in North, Central and South America, the West Indies, Africa, including Madagascar, Asia and in some Pacific Islands as well. In Brazil they occur in a wide range of habitats and climatic zones throughout the country. This study presents reproductive and morphometric data for eleven Brazilian boid species and subspecies (Boa c. contrictor, B. c. amarali, Corallus caninus, Co. hortulanus, Co. cropanii, Epicrates c. cenchria, Ep c. assisi, Ep c. crassus, Eunectes murinus, Eu. deschauenseei and Eu. notaeus) including some morphometric data for Madagascan (Sanzia madagascariensis and Acrantophis dumerili) and Pacific boas (Candoia carinata, Ca. aspera and Ca. bibroni). These large snakes present a very conservative pattern in terms of seasonality in female reproductive cycles, size at maturity, litter and offspring relative size, and reproductive frequency. The reproductive pattern is similar among the boid species we studied and also similar to pythonids. Females' cycles are non-annual and always seasonal, usually with births occurring mostly in the spring-summer. These snakes show sexual dimorphism occurs in mean body length, head size, spur size and stoutness. In species in which males exhibit combat behavior prior to the mating season, mean body size dimorphism is not present (i.e. Ep. cenchria subspecies). Boid males' reproductive cycles are more variable, being continuous or seasonal depending on the species.

SNAKES USED IN ETHNOMEDICINE IN NORTHEAST BRAZIL

This paper documents zootherapeutic practices in Northeast Brazil. It is primarily based on field surveys carried out in fishing villages located in the States of Maranhao and Paraiba, where dwellers provided information on snake species used as medicine, body parts used to prepare the remedies, and the illnesses to which the remedies were prescribed. The species used as medicinal drug and their respective families were: Crotalus durissus (rattlesnake), Bothrops leucurus (‘lance head’, a venomous snake), and Lachesis muta (bushmaster) of the family Crotalidae; and Boa constrictor (boa constrictor), Epicrates cenchria (‘salamanta’), and Eunectes murinus (anaconda) of the family (Boidae). These zootherapeutical resources were used for the cure of 14 illnesses. The most commonly cited species were Crotalus durissus (n=26) e Boa constrictor (n=6), Apparently, the medicinal use of snakes does not pose a threat for their population in the studied sites.

Commercialization and Use of Snakes in North and Northeastern Brazil: Implications for Conservation and Management

Snakes are sold in many markets and religious article stores in Brazil. Besides their use as food, snakes are exploited in a variety of ways, such as pets, or for use in traditional medicine and magic/religious rituals (especially in Afro-Brazilian religions). Despite widespread commercialization, there is a general lack of information about this snake trade, which makes it difficult to evaluate its magnitude and its impact on reptile populations. This work documents the commercialization and use of snakes in five cities in Northeastern (Sao Luis, Teresina, Joao Pessoa and Campina Grande) and Northern (Belem) Brazil, through interviews with 119 merchants of biological products in outdoor markets and religious articles stores. The data was gathered through the use of semi-structured questionnaires, complemented by semi-directed interviews. The products derived from 11 snake species were being commercialized for medicinal or magical/religious purposes. Boa constrictor, Crotalus durissus and Eunectes murinus were the species most commonly sold. The economic importance of snakes as sources of medicines and religious products demonstrates the need for the development of sustainable use programs for these species.

Snake Mating Systems, Behavior, and Evolution: The Revisionary Implications of Recent Findings.

Sexual selection and mating systems profoundly influence the behavior and psychology of animals. Using their own studies of green anacondas (Eunectes murinus) and reviewing other recent studies, the authors conclude that incomplete data derived from a few well-studied snake species have led to general acceptance of polygyny as the dominant mating system in snakes. New data on behavior, paternity, and life history in a diverse taxonomic array of snakes support the view that polyandry is not only common in snakes but may have been the ancestral mating system. This interpretation helps to explain many seemingly paradoxical behavioral differences between lizards and snakes, such as the lack of territorial systems in most snakes and their frequent female-biased sexual size dimorphism.

CUTANEOUS AND PULMONARY MYCOSIS IN GREEN ANACONDAS (EUNCECTES MURINUS)

Two dead, captive green anacondas (Eunectes murinus), including one male and one female, submitted for necropsy were in poor body condition, having multiple, scattered, dark red foci on the scales and mottled lungs. Both snakes had severe mycotic dermatitis. In addition, the male snake had mycotic stomatitis, and the female snake had mycotic pneumonia. Trichophyton sp., Verticillium sp., and Alternaria sp. were isolated from the dermal lesions. The pulmonary lesions were morphologically consistent with Aspergillus sp. Bacterial organisms isolated from skin and internal organs included Chryseobacterium meningosepticum, Stenotrophomonas maltophilia, Aeromonas hydrophila, and Providencia rettgeri. Mycotic diseases can be devastating to reptiles, and suboptimal husbandry and captivity were likely the predisposing factors that led to opportunistic invasion in these snakes.

MEASURING VALUES FOR WETLANDS PROTECTION IN A DEVELOPING COUNTRY FROM DOMESTIC AND INTERNATIONAL CITIZEN GROUPS

MEASURING VALUES FOR WETLANDS PROTECTION IN A DEVELOPING COUNTRY FROM DOMESTIC AND INTERNATIONAL CITIZEN GROUPS

Activity of tabanids (Insecta: Diptera: Tabanidae) attacking the reptiles Caiman crocodilus (Linn.) (Alligatoridae) and Eunectes murinus (Linn.) (Boidae), in the central Amazon, Brazil.

Tabanid females are better known as hematophagous on man and other mammals, and linked to mechanical transmission of parasites. The association between tabanids and reptiles is poorly known, but has been gaining more corroboration through experiments and occasional observation in the tropics. The present study was conducted at a military base (CIGS/BI-2), situated 54 km from Manaus, Amazonas, in a small stream in a clearing (02 degrees 45'33"S; 59 degrees 51'03"W). Observations were made monthly, from April 1997 to March 1998, during two consecutive days. At the same time, other vertebrate animals were offered, including humans. However in this paper only data obtained on a common caiman, Caiman crocodilus (Linn.), and an anaconda, Eunectes murinus (Linn.), in diurnal observations from 05:30 a.m. to 18:30 p.m., will be discussed. A total of 254 tabanid specimens were collected, 40 from the anaconda and 214 from the caiman. Four tabanid species were recorded on these two reptiles: Stenotabanus cretatus Fairchild, S. bequaerti Rafael et al., Phaeotabanus nigriflavus (Kröber) and Tabanus occidentalis Linn. Diurnal activities showed species-specific patterns. The first three species occurred only in the dry season. T. occidentalis occurred during the whole observation period, and with increased frequency at the end of the dry season. We observed preferences for body area and related behavior of the host. Observations on the attack of tabanids on one dead caiman are also presented.

Infectious disease serologic survey in free-ranging Venezuelan anacondas (Eunectes murinus).

Reptiles can harbor pathogenic microorganisms asymptomatically and serve as potential reservoirs of infection for humans, domestic animals, and other reptiles. Infectious diseases are also problematic for free-ranging reptile populations and are an important consideration in reptile reintroduction and translocation projects. There have been limited serologic studies of free-ranging reptiles for evidence of exposure to potential pathogens. In the present study, serum or plasma samples from five male and five female free-ranging Venezuelan anacondas (Eunectes murinus) were screened for antibodies to eastern, western, and Venezuelan equine encephalitis viruses, vesicular stomatitis virus, ophidian paramyxovirus, 19 Leptospira interrogans serovars, and Cryptosporidium serpentes. Antibodies to these agents were not detected, or antibody titers were low and possibly nonspecific. These results for the limited number of anacondas surveyed suggest that they do not serve as significant reservoirs for these infectious agents at this location.

Alveolar and saccular lung phospholipids of the anaconda, Eunectes murinus

Phospholipids and their mode of synthesis in lung samples from the alveolar and saccular regions of an anaconda (Eunectes murinus) were investigated by standard techniques of chloroform–methanol extraction and two-dimensional thin-layer chromatography. The alveolar lung has six times as much phosphatidylcholine in its lung wash lipid extract as saccular lung. Phosphatidylcholine and sphingomyelin are the two principal phospholipids of the tissue of both lungs. Alveolar lung incorporates a higher percentage although a smaller total amount of [1-14C]acetate (54%) into phosphatidylcholine (including lysophosphatidylcholine), whereas saccular lung only incorporates 8% [1-14C]acetate into phosphatidylcholine (including lysophosphatidylcholine) and 60% [1-14C]acetate into sphingomyelin. Saccular lung synthesized 31% disphosphatidylglycerol from [1-14C]acetate; alveolar lung did not synthesize any. Surface tension plots of lung wash lipid extracts show slight surpellic activity with minimum surface tensions of 22 dyn/cm (1 dyn = 10 μN) for both alveolar and saccular lung, at 37 °C.

Redescription of Amblyomma fulvum Neumann 1899 (Acarina: Ixodidae), a parasite of the giant anaconda in northern South America.

Amblyomma fulvum Neumann is redescribed and figured for the first time from a male taken from the giant anaconda Eunectes murinus Linnaeus.

Metastasizing lymphosarcoma in a giant snake, Eunectes murinus (Linnaeus, 1758)

This report of a tumor of the hematopoietic system in an anaconda snake, Eunectes murinus, is the first of such a growth in a reptile. The primary site was apparently in undifferentiated mesenchymal cells in the liver and secondarily deposits occurred in the thyroid, spleen, pancreas, and kidneys. The lymphoblast was the predominant cell type in all of these organs; hence the tumor is designated as a lymphosarcoma.

XII. On the structure and development the skull in the common snake (tropidonotus natrix)

The most important work on the development of this type appeared as long ago as 1839. It was by the late Professor H. Rathke, 'Entwickelungsgeschichte der Natter ( Coluber natrix ).’ Konigsb., 4to. From time to time during the last twelve years I have worked at the Snake’s skull, my guide being Professor Huxley’s translation of so much of Rathke’s work as bears especially upon my line of research; this I have had at hand, both in the 4 'Croonian Lecture’ and in the ‘Elements of Comparative Anatomy.’ My earliest studies of the embryonic conditions of the Snake’s skull were made on half-grown embryos of the Python ( Python Sebæ ), and of the Anaconda ( Eunectes murinus ); these were the gift of my friends Dr. Edwards Crisp, F. Z. S., and Dr. P. L. Sclater, F. R. S. Meantime I have been acquiring younger and still younger specimens of the Common Snake, but only lately have I succeeded in obtaining any embryos sufficiently immature for my first and second stages. During the last winter (February, 1877) these earlier stages happily came to hand. At the instance of Mr. P. H . Carpenter, M. Braun, of Wurzburg, sent me a considerable number of reptilian embryos in very early stages, from Professor Semper’s laboratory. These included, besides the longed-for specimens of the Common Snake, others of the Blind Worm ( Anguis fragilis ), the Nimble Lizard ( Lacerta agilis ), and the Gecko ( Platydactylus ). These other three types I intend to work out in due time. The Snake has the simplest skull of all; and yet, simple as it is, it is a key to that of any member of that great bundle of Vertebrate life which, including the reptiles and birds, is termed “Sauropsida.” (See Huxley, “On the Classification of Birds,” Proc. Zool. Soc., April 11th, 1867, pp. 415-472.)