Coral Snake Research Articles

Reproduction, seasonal activity and growth of the coral snake, Micrurus corallinus (Elapidae), in the southeastern Atlantic forest in Brazil

AbstractDissection of 360 specimens of the coral snake Micrurus corallinus, combined with data on captive individuals and field observations, provided information on the reproductive ecology of this elapid snake. Clutch size ranged from 2 to 12 eggs, and was correlated with maternal body size. Reproduction seems to be highly seasonal, with mating and vitellogenesis occurring at the onset of the rainy season, oviposition in mid rainy season, and hatching at the end of the rainy season and early dry season. Incubation in the laboratory ranged from 78 to 93 days. Neonates measured 177-197 mm snout-vent length and weighed 2.02-2.76 g. Growth of juveniles is quick, with both males and females attaining sexual maturity at an age of about 18 months. Seasonal patterns of surface activity seem to be related to age and sex.

Characterization of the Lower‐Molecular‐Mass Fraction of Venoms from Dendroaspis Jamesoni Kaimosae and Micrurus Fulvius Using Capillary‐Electrophoresis Electrospray Mass Spectrometry

Capillary electrophoresis (CE) with electrospray ionization (ESI) and selected ion-monitoring mass-spectrometric (SIM-MS) detection has been used to provide as much information as possible about the lower molecular-mass fraction (peptides of molecular masses up to 8500 Da) of the venoms of Dendroaspis jamesoni kaimosae (Jameson's Mamba) and Micrurus fulvius (Eastern Coral Snake). Method development was based on the venom of D. jamesoni kaimosae, which contains some previously described peptides, with subsequent application to the completely unknown venom of M. fulvius. CE-ESI-SIM-MS provides a rapid and extremely sensitive method for the detection and molecular-mass determination of peptides present in venoms. It has been utilized to provide molecular masses and thus, by inference, confirmation of the peptide compositions for those toxins which have been previously described in the literature. Our methodology indicates the presence of 83 peptides in the venom of D. jamesoni kaimosae and 49 peptides in the venom of M. fulvius in the molecular-mass range 6000-8500 Da.

Anesthetic Implication of Snake-Bite Envenomation

Anesthetic Implication of Snake-Bite Envenomation

A Phylogenetic Analysis of the New World Coral Snakes (Elapidae: Leptomicrurus, Micruroides, and Micrurus) Based on Allozymic and Morphological Characters

The phylogenetic relationships of 18 species of New World snakes (Elapidae: Leptomi- crurus, Micruroides, and Micrurus) were examined with morphological and allozymic characters analyzed by parsimony. Two species of kraits (Elapidae: Bungarus) were included as outgroups. Coral snake mor- phology was found to be very conservative and few informative morphological characters were found. The general relationships of all snakes are discussed in light of the morphological synapomorphies identified in this study. The results indicate that Micrurus is paraphyletic because of the exclusion of Leptomicrurus. This is rectified by placing Leptomicrurus into the synonymy of Micrurus. The New World snakes are a large group of small to moderate-sized, dangerously ven- omous snakes in the family Elapidae. The 61 species currently recognized are divided among three genera: Micrurus (57 species), Leptomicru- rus (three species), and Micruroides (one species). Micrurus is found in a wide range of terrestrial habitats throughout its range from the south- eastern United States to southern South Amer- ica. Leptomicrurus is found in tropical lowland moist and wet forests in Amazonia. The mono- typic Micruroides is found in the Sonoran Desert of the southwestern United States and adjacent northwestern Mexico. Although various Old World elapids (e.g., Calliophis, Maticora, Aspi- delaps) are often termed coral snakes, the term is restricted herein to New World elapids.

Emergency Management of Poisonous Snakebites.

In brief Though 42 snake species in the United States can inflict a poisonous bite, management is the same for 99% of bites because 99% of bites are inflicted by pit vipers. First aid instructions stressing rapid transit to a hospital apply to all bites. Surgical intervention has no place in acute snakebite treatment. Antivenin therapy is appropriate except in cases of mild pit viper envenomation. Pit viper antivenin is the right choice for any pit viper envenomation, and the patient history will guide the choice of coral snake antivenin. For any antivenin administration, care must be taken to prevent allergic reactions. Basic supportive care involves pain control, correcting metabolic and hematologic complications, keeping the patient comfortable, and preventing serum sickness.

Experimental Studies of Coral Snake Mimicry: Generalized Avoidance of Ringed Snake Patterns by Free-Ranging Avian Predators

Summary 1. Plasticine snake replicas were used to demonstrate that free-ranging avian predators generalize avoidance of Coral Snake ringed patterns to similar patterns, supporting the argument that the convergence on ringed and banded patterns among neotropical snakes is a result of the mimetic advantage of resembling venomous Coral Snakes. 2. The study was conducted at a tropical dry forest site in Costa Rica, where only one species of Coral Snake occurs. The Coral Snake has a tricolour (red-yellow-blackyellow-red) ringed pattern and no snakes at the site have bicolour (red-black) ringed patterns. Neither tricolour nor bicolour ringed replicas were attacked by birds, whereas an unmarked brown replica was. 3. The avoidance of the bicolour ringed pattern is attributable to generalized avoidance of Coral Snake-like patterns. No red-and-black ringed prey have been observed at the site, so birds could not have learned specific avoidance of the bicolour pattern. Historical biogeographical evidence suggests that the avifauna at the site did not evolve in the presence of red-and-black ringed snakes, so it is unlikely that birds evolved a specific innate avoidance of the bicolour ringed pattern.

Survival Rates of Puerto Rican Birds: Are Islands Really That Different?

Ph.D. dissertation, Univ. Minnesota, Minneapolis. CALDWELL, G. S., AND R. W. RUBINOFF. 1983. Avoidance of venomous sea snakes by naive herons and egrets. Auk 100:195-198. COPPINGER, R. P. 1969. The effect of experience and novelty on feeding behavior with reference to the evolution of warning coloration in butterflies. I. Reactions of wild-caught adult Blue Jays to novel insects. Behaviour 35:45-60. GWINNER, E. 1964. Untersuchungen iiber das Ausdrucksund Sozialverhalten des Kolkraben (Corvus corax L.). Z. Tierpsychol. 21:657-748. HEINRICH, B. 1988a. Winter foraging at carcasses by three sympatric corvids, with emphasis on recruitment by the raven, Corvus corax. Behav. Ecol. Sociobiol. 23:141-156. HEINRICH, B. 1988b. Why do ravens fear their food? Condor 90:950-952. HEINRICH, B. 1989. Ravens in winter. Summit Books of Simon & Schuster, New York. HEINRICH, B. 1995. Neophila and exploration in juvenile Common Ravens, Corvus corvax. Anim. Behav. 50:695-704. JAMES, F. C. 1971. Ordinations of habitat relationships among breeding birds. Wilson Bull. 83:215235. MARZLUFF, J. 1988. Do Pinyon Jays alter nest placement based on prior experience? Anim. Behav. 36:1-10. MARZLUFF, J., AND B. HEINRICH. 1991. Foraging by Common Ravens in the presence and absence of territory holders: An experimental analysis of social foraging. Anim. Behav. 42:755-770. ROPER, T. J. 1990. Responses of domestic chicks to artificially coloured insect prey: Effects of previous experience and background colour. Anim. Behav. 39:466-473. SCHULER, W., AND E. HESSE. 1985. On the function of warning coloration: A black and yellow pattern inhibits prey-attack by naive domestic chicks. Behav. Ecol. Sociobiol. 16:249-255. SMITH, S. M. 1975. Innate recognition of coral snake pattern by a possible avian predator. Science 187: 759-760. STIEHL, R. B. 1978. Aspects of the ecology of the Common Raven in Harney Basin, Oregon. Ph.D. dissertation, Portland State Univ., Portland, Oregon.

Coral Snake (Micrurus Fulvius Fulvius) Envenomation In Five Dogs: Present And Earlier Findings

SummaryThe purpose of this study is to report on five cases of coral snake envenomation in the dog to substantiate earlier findings in four dogs reported previously, and to describe any additional clinical features that have not yet been noted. The combined results from both studies allow for a more accurate projection of the frequency of certain clinical signs. Both groups showed signs of lethargy, lower motor neuron weakness (8 of 9 dogs) and varying hematologic changes with hemolysis and hemoglobinuria occurring most commonly (7 of 9 dogs). Cardiac dysrhythmias were recorded infrequently (2 of 9 dogs). Not reported previously was the presence of a subtle bite wound located on the upper or lower lip of three dogs in the present series. An unexpected finding in this second series was the occurrence of an anaphylactoid reaction in one dog presumably attributed to the antivenin. Close examination of the lip might reveal the site of envenomation (as found in 4 of 9 dogs from both studies). Treatment with coral snake antivenin should be given as early as possible and followed by close observation for signs of anaphylaxis. The results of this study substantiate earlier findings and provide for a larger data base for further reference.

Reverse Biology Applied toMicrurus corallinus, a South American Coral Snake

AbstractLittle is known about the coral snakes venom components. Clarification of the primary structure of polypeptidic toxins was hampered until now by the lack of enough venom for protein purification and chemistry. Using the Reverse Biology approach, several potential Micrurus corallinus toxins were characterized by cDNA cloning. The deduced proteins shared homology with known snake toxins, such as α-neurotoxins, phospholipase A2, natriuretic peptides and lectins. To our knowledge, these are the first complete primary structure characterization of coral snake venom toxins.

Local effects induced by venoms from five species of genus Micrurus sp. (coral snakes)

Venoms from five species of Micrurus (coral snakes) from Brazil (Amazonas State) were tested for the following effects: edematogenic, myotoxic, coagulant, hemorrhagic and phospholipase A2 (PLA2) detection. None of the venoms tested presented coagulant activity. The presence of PLA2 was detected by ELISA in the venoms of M. spixii, M. averyi and M. lemniscatus. The myotoxicity was estimated by the increase in the serum creatine kinase level and by histological analysis. All venoms, except that from M. surinamensis, induced intense edematogenic and myotoxic effects. The venom of M. averyi showed hemorrhagic activity which was confirmed by histopathological analysis. This is the first evidence of such an effect by coral snake venom.

Oxygen uptake in snakes: is there a reduction in fossorial species?

Oxygen uptake of the fossorial blind snake ( Typhlops reticulatus) and the semifossorial coral snake ( Micrurus ibiboboca) was measured at 20 and 30°C. Oxygen uptake of blind snakes was within the normal range, whereas oxygen uptake of coral snakes was in the lower end of values reported for snakes. The results do not support the hypothesis of reduced oxygen uptake in fossorial reptiles.

On the Phylogenetic Relationship of Colubrinae, Elapidae, and Viperidae and the Evolution of Front-Fanged Venom Systems in Snakes

Phylogenetic relationships among major clades of advanced snakes and the origin of the front-fanged venom systems of elapids and viperids have been the focus of considerable study and debate during the past century, but a general consensus on the resolution of these questions has not been reached. Here we compare DNA sequences of portions of the mitochondrial small and large subunit ribosomal RNA genes for representatives of three major clades of advanced snakes: an elapid (Naja naja), a viperid (Vipera ammodytes), a colubrine (Coluber constrictor), and, for an outgroup, a boid (Boa constrictor). Phylogenetic analysis indicates a close relationship between the elapid and colubrine relative to the viperid. This finding is congruent with the immunological data of Cadle (1988). Essentially no support was found for the hypothesis of a single origin for frontfanged venom systems and sister status for viperids and elapids, as first proposed by Cope (1900). The hypothesis of a basal position for elapids, as proposed by McDowell (1986), was refuted. T WO major groups of snakes possess large, muscular, temporal venom glands and subocular venom ducts leading to front fangs. Elapidae (cobras, kraits, coral snakes, sea snakes, and their allies) constitutes one group, Viperidae (vipers and pitvipers) the other. With the possible exclusion of a small number of prob

DIFFERENTIAL AVOIDANCE OF CORAL SNAKE BANDED PATTERNS BY FREE-RANGING AVIAN PREDATORS IN COSTA RICA.

Empirical studies of mimicry have rarely been conducted under natural conditions. Field investigations of some lepidopteran systems have provided a bridge between experiments examining artificial situations and the mimicry process in nature, but these systems do not include all types of mimicry. The presence of dangerous or deadly models is thought to alter the usual rules for mimicry complexes. In particular, a deadly model is expected to protect a wide variety of mimics. Avoidance of different types of mimics should vary according to how closely they resemble the model. Coral snake mimicry complexes in the neotropics may provide natural systems in which these ideas can be examined, but there is no direct evidence that the patterns of venomous coral snakes or potential mimics are avoided in the wild. Plasticine replicas of snakes were used to assess the frequency of avian predation attempts as a function of color pattern. Avian predators left identifiable marks on the replicas, the position of which indicated that replicas were perceived as potentially dangerous prey items by birds. The number of attacks on unmarked brown replicas was greater than that on tricolor coral snake banded replicas. This result was true whether replicas were placed on natural or plain white backgrounds, suggesting that coral snake banded patterns function aposematically. In a separate experiment, replicas representing all six patterns of proposed coral mimics at the study site were attacked less often than unmarked brown replicas. Within these six banded patterns, some were attacked significantly more often than others. This study provides direct field evidence that coral snake banded patterns are avoided by free-ranging avian predators and supports theoretical predictions about mimicry systems involving deadly models.

Differential Avoidance of Coral Snake Banded Patterns by Free-Ranging Avian Predators in Costa Rica

Differential Avoidance of Coral Snake Banded Patterns by Free-Ranging Avian Predators in Costa Rica

Experimental myonecrosis induced by the venoms of South American Micrurus (coral snakes)

Venoms from 11 taxa of Micrurus (coral snakes) from Brazil and Colombia were tested for myotoxic activity in mice. All venoms, except that of M. surinamensis, induced myotoxicity as judged by the increase in plasma creatine kinase levels and by histological analysis. Qualitatively, these venoms induced a similar necrotic pattern, although there were conspicuous quantitative differences between them.

The colouration of the venomous coral snakes (family Elapidae) and their mimics (families Aniliidae and Colubridae)

The bright coloured, highly venomous coral snakes, Leptomicrurus, Micrurus and Micruroides (family Elapidae) and a series of harmless or mildly toxic mimics form an important component of the snake fauna of the Americas. Coral snake patterns are defined as any dorsal pattern found in any species of venomous coral snake and/or any dorsal pattern containing a substantial amount of red, pink or orange distributed so as to resemble that of some species of venomous coral snake. The components of coral snake colouration are described and four principal dorsal patterns are recognized: unicolour, bicolour, tricolour and quadricolour. The tricolour patterns may be further clustered based on the number of black bands or rings separating the red ones as: monads, dyads, triads, tetrads or pentads. A detailed classification of all coral snake colour patterns is presented and each pattern is illustrated. The taxonomic distribution of these patterns is surveyed for mimics and the 56 species of highly venomous coral snakes. Among the latter, the most frequent encountered patterns are tricolour monads, tricolour triads and bicolour rings, in that order. No venomous coral snakes have a tricolour dyad, tricolour tetrad or quadricolour pattern. As many as 115 species of harmless or mildly toxic species, c. 18% of all American snakes, are regarded as coral snake mimics. The colouration and behavioural traits of venomous coral snakes combine to form a significant antipredator defence of an aposematic type. The mimics in turn receive protection from predators that innately or through learning avoid coral snake colour patterns. The precise resemblances in colouration between sympatric non-coral snakes and venomous coral snakes and the concordant geographic variation between the two strongly support this view. Batesian mimicry with the highly venomous coral snakes as the models and the other forms as the mimics is the favoured explanation for this situation. It is further concluded that a number of species in the genera Elaphe, Farancia, Nerodia and Thamnophis, although having red in their colouration, should not be included in the coral snake mimic guild.

The biological properties of venoms of some american coral snakes (Genus Micrurus)

1. 1. The biological properties of nine venom samples from six taxa of Micrurus were investigated. The venoms exhibited low protease, phosphodiesterase and 5′-nucleotidase activities, moderate to strong phospholipase A and hyaluronidase activities, variable l-amino acid oxidase activity and were devoid of arginine ester hydrolase and thrombin-like activities. Some venom samples exhibited strong acetylcholinesterase activity. Venoms of M. c. dumerili and M. frontalis exhibited exceptionally high alkaline phosphomonesterase activity while two of the M. f. fulvius venom samples tested exhibited strong hemmorrhagic activity in mice. 2. 2. The polyacrylamide gel electrophoretic patterns of the venoms indicate that most of the Micrurus venom proteins are basic proteins. All Micrurus venoms tested exhibited similar SDS-polyacrylamide gel electrophoretic patterns, with an intense low mol.wt protein band. 3. 3. The Micrurus venoms appear to exhibit biological properties similar to other elapid venoms found in Asia and Africa. There are, however, no common characteristics in the biological properties of the venoms examined at the generic level.

Treatment of snakebite poisoning

The epidemiology, mechanics, prevention, pharmacology, clinical manifestations, and treatment of snakebites are reviewed. Poisonous snakes bite approximately 8000 persons annually in the United States, causing approximately 12-15 deaths per year. Pit vipers (rattlesnakes, copperheads, cottonmouths, and massasaugas) are responsible for 99% of all snakebite poisonings; coral snakes and other foreign exotic species are responsible for the additional 1%. Envenomation is characterized by pain, edema, and ecchymoses at or near the site of venom injection, followed by cardiac, hematologic, neurologic, renal, and pulmonary toxicity. The major clinical finding in most snakebite poisonings is local tissue necrosis. Immediate treatment for snakebite includes limiting movement and placing a constriction band proximal to the site of venom injection. If medical care is more than 30 minutes away, the wound may be incised and suctioned. Antivenin therapy is the mainstay of medical treatment of snakebite, along with administration of plasma expanders, pain medication, diazepam, tetanus toxoid, antiseptics, and antibiotics. Patients who have pain, swelling, ecchymoses, systemic symptoms, or abnormal laboratory findings within 30 minutes to one hour of a bite are probable candidates to receive antivenin therapy. Before receiving antivenin therapy, the patient must be tested for hypersensitivity to the antivenin. Antivenin therapy is most effective when given within four hours of the snakebite. Pharmacists--especially those serving rural areas--should be familiar with current snakebite treatments, both local and systemic, and should be prepared to provide important information and dispel any myths about snakebite poisoning.

Some new species of Caryospora (Apicomplexa: Eimeriidae) from brazilian snakes, and a re-description of C. jararacae Carini, 1939

The mature ooxysts of six new species of Caryospora are described from the faeces of Brazilian snakes. They are differentiated from other species previously recorded from reptiles, largely on the size and shape of the oocyst and sporocyst, structure of the oocyst wall, and presence or absence of a polar body. C. paraensis n. sp., and C. carajasensis n. sp., are from the false coral, Oxyrhopus petola digitalis; C. pseustesi n. sp., from the egg-eater, Pseustes sulphureus sulphureus; C. epicratesi n. sp., from the red boa, Epicrates cenchria cenchria; and C. micruri n. sp., and C. constancieae n. sp., from the coral snake, Micrurus spixii spixii. A re-description is given of C. jararacae Carini, 1939, from the jararaca Bothrops atrox, embodying some additional morphological features.

Comparative chromatography of Brazilian coral snake ( Micrurus venoms

1. 1. Elution profiles of 11 coral snake venoms, including those of Micrurus albicinctus, M. corallinus, M. frontalis altirostris, M. f. brasiliensis, M. f. frontalis, M. fulvius fulvius, M. ibiboboca, M. lemniscatus ssp., M. rondonianus, M. spixii spixii and M. surinamensis surinamensis, were compared using high performance gel filtration and reverse phase media. 2. 2. Micrurus venom profiles were compared with those of “outgroup” taxa Bothrops moojeni, Naja naja kaouthia and Bungarus multicinctus. 3. 3. Purified elapid venom constituents were also chromatographed under identical conditions in order to suggest possible identities of Micrurus venom constituents. 4. 4. Masses of various components were confirmed by mass spectrometry. 5. 5. Phospholipase constituents in three venoms were positively identified based on their reverse phase chromatograms. 6. 6. Venoms of M. rondonianus and M. s. surinamensis are shown to be significantly different in their peptide composition from other Micrurus venoms.