Reproduction and feeding of the colubrid snake Tomodon dorsatus from south-eastern Brazil

2005 ◽  
Vol 26 (1) ◽  
pp. 33-38 ◽  
Author(s):  
Ivan Sazima ◽  
Otavio Marques ◽  
Alessandra Bizerra
Keyword(s):  
Body Size ◽  
Sexual Dimorphism ◽  
Rainy Season ◽  
Feeding Behaviour ◽  
South Eastern ◽  
Eastern Brazil ◽  
Body Sizes ◽  
Upper Jaw ◽  
Reproductive Cycles ◽  
Clutch Mass

AbstractBody size, sexual dimorphism, reproductive cycles, fecundity, diet and feeding behaviour of the colubrid snake Tomodon dorsatus from south-eastern Brazil were studied. Females of this viviparous species attained larger body sizes than males, the latter maturing with smaller body size than the former. Vitellogenesis occurred at the onset of rainy season, ovulation by mid rainy season, and parturition from late dry to early rainy season. Reproductive cycle was extended, maybe as a consequence of the low metabolism and food intake. Litter size ranged 4-26 offspring and was correlated with maternal body size. Relative clutch mass ranged 0.48-0.82, and neonates ranged 12-17 cm in snout-vent length. Tomodon dorsatus was shown to feed exclusively on veronicellid slugs quickly swallowed by long excursions of the specialized upper jaw units.

Reproductive biology of the false coral snake Oxyrhopus guibei (Colubridae) from southeastern Brazil

2002 ◽  
Vol 23 (4) ◽  
pp. 495-504 ◽  
Author(s):  
Otavio Marques ◽  
Lígia Pizzatto
Keyword(s):  
Body Size ◽  
Reproductive Biology ◽  
Rainy Season ◽  
Reproductive Activity ◽  
Climatic Conditions ◽  
Southeastern Brazil ◽  
Coral Snake ◽  
Males And Females ◽  
Reproductive Cycles ◽  
Number Of Individuals

AbstractThe reproductive biology of the false coral snake, Oxyrhopus guibei, was studied through dissection of 496 specimens, combined with observations on captive individuals. Males mature with smaller body size than females, females attain much larger body size, and male-male combat is not expected. Clutch size ranged from 3 to 20, and was correlated with female length. Reproductive cycles in both males and females seem to be continuous, with vitellogenesis and spermatogenesis occurring throughout the year. Reproductive activity in both sexes decreased at the end of the rainy season possibly due to previous intense reproductive activity in more favorable climatic conditions. The smaller number of individuals collected at the end of the rainy season apparently occurs due to the decrease of reproductive activity of this snake.

Seed bank and seed rain in a seasonal semi-deciduous forest in south-eastern Brazil

2002 ◽  
Vol 18 (5) ◽  
pp. 759-774 ◽  
Author(s):  
Maria Tereza Grombone-Guaratini ◽  
Ricardo Ribeiro Rodrigues
Keyword(s):  
Seed Bank ◽  
Rainy Season ◽  
Deciduous Forest ◽  
Similarity Index ◽  
Seed Rain ◽  
Seasonal Effects ◽  
South Eastern ◽  
Eastern Brazil ◽  
Annual Total ◽  
Dry Seasons

To examine the influence of seasonality on the abundance and composition of species in the community, we studied the seed rain and the seed bank in a seasonal, semi-deciduous forest in south-eastern Brazil. Soil samples (depth 3 cm, 0.25 m2) were collected within a 1-ha plot in the dry seasons of 1996 and 1997 and the rainy season of 1997 (84 samples per collection). Thirty-five seed traps (0.25 m2 each) were placed randomly in the forest from March 1997 to February 1998. The greatest density of seeds in the soil occurred in samples collected during the rainy season, the period which coincides with the main fruiting period in this forest. The Sørensen similarity index values for the seed bank composition among the three periods were high (> 0.50). The fallout of propagules was strongly seasonal, with more than half of the annual total number of seeds being caught in the two months around the end of the dry season and beginning of the rainy season. The mean density of seeds in the soil bank was nearly 86% lower than the seed rain density. There was no clear evidence of seasonal effects on species density and richness in this forest.

Avian Egg Morphometrics - Allometric Models of Egg Volume, Clutch Volume and Shape

1994 ◽  
Vol 42 (3) ◽  
pp. 307 ◽  
Author(s):  
PD Olsen ◽  
RB Cunningham ◽  
CF Donnelly
Keyword(s):  
Body Weight ◽  
Body Size ◽  
Sexual Dimorphism ◽  
Clutch Size ◽  
Egg Volume ◽  
Simple Power ◽  
Wide Range ◽  
Body Weights ◽  
Body Sizes ◽  
Simple Power Function

This paper describes three comprehensive new models of the allometric relationships between egg volume, clutch volume and shape, and body weight. Mean egg dimensions, clutch sizes and adult body weights were obtained for 326 species, mainly of four bird types: raptors (including owls), shorebirds, frogmouths (including nightjars), and storks (including the New World vultures). These are groups in which there is a wide range of body sizes and of sexual dimorphism in body size (in direction and degree). Female body weight alone accounted for 92% of the variation in egg volume. Sexual dimorphism in body size, phylogenetic relationship, and clutch size were significant contributors to the model of egg volume; their addition increased the explained variance to over 98%. The model was curvilinear (quadratic) in form, rather than linear as assumed in previous models. Larger species laid smaller eggs than expected under a simple power function. For the fitted model, within bird types, generic groupings had parallel curvilinear slopes but differing intercepts. Between bird types, the slopes differed. Clutch volume was scaled to body weight; all the bird types had a common slope, which was curvilinear. Body weight and dimorphism accounted for 89.5% of the variation in clutch volume. For all bird types, eggs became proportionally longer in shape as body weight increased, according to a simple power law. The relevance of these relationships to hypotheses on the evolution and adaptive significance of sexual dimorphism and to the trade-off between egg size and clutch size is discussed briefly.

Allometry and sexual dimorphism in the lung morphology of prairie rattlesnakes, Crotalus viridis viridis

1999 ◽  
Vol 20 (4) ◽  
pp. 377-389 ◽  
Author(s):  
J. Scott Keogh ◽  
V. Wallach
Keyword(s):  
Body Size ◽  
Sexual Dimorphism ◽  
Intraspecific Variation ◽  
Relative Length ◽  
Single Population ◽  
Crotalus Viridis ◽  
Lung Morphology ◽  
Body Sizes ◽  
Vascular Component

AbstractWe quantified sexual dimorphism and allometric changes in the lung morphology of 160 juvenile and adult specimens of prairie rattlesnake, Crotalus viridis viridis, from a single population. In virtually all lung components, those of males are located more posteriorly than are those of females of the same body size. Males display a longer vascular component than females but there is no sexual dimorphism in size of the avascular component. Thus, males generally have longer lungs than do females at all body sizes. With increasing body size, the lung components are found more anteriorly, relative length of the vascular lung decreases, and relative length of the avascular lung increases in both sexes. However, total lung length increases isometrically with body size. These sexual and allometric differences suggest that intraspecific variation should be taken into account when lung size characters are used in snake systematic studies.

Interpopulational variation in sexual dimorphism, reproductive output, and parasitism of Liophis miliaris (Colubridae) in the Atlantic forest of Brazil

2006 ◽  
Vol 27 (1) ◽  
pp. 37-46 ◽  
Author(s):  
Lígia Pizzatto ◽  
Otavio Marques
Keyword(s):  
Body Size ◽  
Sexual Dimorphism ◽  
Atlantic Forest ◽  
Reproductive Output ◽  
Sexual Size Dimorphism ◽  
The Other ◽  
Female Body Size ◽  
Body Sizes ◽  
Northern Atlantic ◽  
Males And Females

AbstractSexual maturity, sexual dimorphism, reproductive output, and parasitism of the colubrid snake Liophis miliaris were compared among populations inhabiting four regions of Brazil: (1) northern coastal Atlantic forest, (2) southern coastal Atlantic forest, (3) northern inland Atlantic forest (4) southern inland Atlantic forest. Females delayed maturity and attained larger body sizes than males in all regions. Males and females from northern Atlantic forest were smaller and attained maturity with a smaller body size than males of other regions. The sexual size dimorphism index ranged from 0.19 to 0.23 and was lowest in the northern Atlantic forest. There was no sexual dimorphism in head length in any of the populations studied. Clutch size was similar in all populations and increased with maternal body size. The reproductive frequency was lower in the northern coastal Atlantic forest and in contrast to the other regions, tended to increase with female body size. The nematoda Ophidiascaris sp. and cystacanths of Oligacanthorynchus spira (Acanthocephala) occurred equally in both sexes. Fewer snakes from the northern coastal Atlantic forest were infested by parasites compared to the other regions and parasitism apparently did not influence reproduction.

scholarly journals Reproductive biology of the Amazon Lava Lizard (Tropidurus torquatus) from the Wet Chaco of Corrientes (Argentina): congeneric comparisons of ecotypic and interspecific variations

2014 ◽  
Vol 92 (7) ◽  
pp. 643-655 ◽  
Author(s):  
M.A. Ortiz ◽  
J.M. Boretto ◽  
C. Piantoni ◽  
B.B. Álvarez ◽  
N.R. Ibargüengoytía
Keyword(s):  
Body Size ◽  
Reproductive Biology ◽  
Fat Body ◽  
Tail Length ◽  
Reproductive Activity ◽  
Hatching Time ◽  
Fat Bodies ◽  
Reproductive Cycles ◽  
Lava Lizard ◽  
Clutch Mass

Herein we describe the reproductive biology of a population of the Amazon Lava Lizard (Tropidurus torquatus (Wied-Neuwied, 1820)) from Corrientes, northeastern Argentina (Wet Chaco). We describe the male and female reproductive cycles, minimum body size for adults, reproductive output, mean relative clutch mass, fat body cycles, and sexual dimorphism. Our results were compared with data on the reproductive biology of Brazilian populations of T. torquatus and congeneric species. In Corrientes, males of T. torquatus exhibited a continuous reproductive cycle, but with annual variation of testicular parameters associated with spermatogenic activity. In contrast, females were reproductive only from winter to summer (July–February), laying at least two clutches each of six eggs, on average, per reproductive season. The relative clutch mass and egg size values in Corrientes were the highest reported for the species. The annual cycle of energy storage (as fat bodies) was inversely correlated with reproductive activity in both sexes. Males differed from females in snout–vent length, head size, interlimb length, and tail length. We observed interpopulational differences in relative clutch mass, egg volume and mass, incubation period and hatching time, and the minimum body size for sexual maturity probably as a result of phenotypic plasticity or adaptation to local environmental conditions and likely both.

Growth, maturity, and sexual dimorphism in the wood turtle, Clemmys insculpta

1990 ◽  
Vol 68 (4) ◽  
pp. 672-677 ◽  
Author(s):  
Jeffrey E. Lovich ◽  
Carl H. Ernst ◽  
John F. McBreen
Keyword(s):  
Body Size ◽  
Sexual Dimorphism ◽  
Carapace Length ◽  
Sexual Size Dimorphism ◽  
Von Bertalanffy ◽  
Size Dimorphism ◽  
Adult Females ◽  
Body Sizes ◽  
Von Bertalanffy Growth Model ◽  
Wood Turtle

Growth in the wood turtle (Clemmys insculpta) is described using the von Bertalanffy growth model and nonlinear regression. Growth in both sexes is similar until about 160 mm plastron length. Males grew at a faster rate after this size. Males appear to mature at a larger size and later age than females, although age-specific body size is highly variable. Sexual size dimorphism, in carapace length, is pronounced, with males attaining mean body sizes significantly larger (1.07–1.10 times) than those of adult females. Plastron length is an inappropriate measure of sexual size dimorphism because of the development of plastral concavity in males. Females tend to predominate in samples, possibly owing to differential maturity of the sexes. The direction of sexual size dimorphism may be maintained by intrasexual competition among males for access to females. Data for several adults captured at intervals of from 9 to 20 years support the concept of indeterminate growth.

Pythons in the pergola: the ecology of 'nuisance' carpet pythons (Morelia spilota) from suburban habitats in south-eastern Queensland

2001 ◽  
Vol 28 (6) ◽  
pp. 573 ◽  
Author(s):  
S. Fearn ◽  
B. Robinson ◽  
J. Sambono ◽  
R. Shine
Keyword(s):  
Body Size ◽  
Food Habits ◽  
Sexual Size Dimorphism ◽  
Activity Patterns ◽  
Dietary Composition ◽  
Seasonal Activity ◽  
Size Dimorphism ◽  
South Eastern ◽  
Two Cities ◽  
Body Sizes

Carpet pythons (Morelia spilota) are large (to >4 m, 11 kg) non-venomous snakes that are widely distributed across mainland Australia. In many parts of their range, viable populations persist even in highly disturbed urban and suburban habitats. Over a six-year period, we collected 258 ‘nuisance’ pythons from two cities (Brisbane and Ipswich) in south-eastern Queensland. Most of these snakes were reported by members of the general public, often after the snakes had consumed domestic pets or cage-birds. We provide data on seasonal activity patterns, body sizes, sexual size dimorphism, reproduction and food habits of these snakes. Snakes were active and fed year-round, primarily on domestic and commensal birds and mammals. Dietary composition shifted with body size: one small snake consumed a lizard, intermediate-sized snakes took mostly mice, rats and parrots, and large snakes fed on larger items such as cats, brushtail possums and poultry. Adult male pythons engaged in combat bouts during the breeding season, and (perhaps as an adaptation to enhance success in such bouts) grew larger and were more heavy-bodied than conspecific females.

Growth and body size in Blanding's turtles (Emydoidea blandingi): relationships to reproduction

1991 ◽  
Vol 69 (1) ◽  
pp. 239-245 ◽  
Author(s):  
Justin D. Congdon ◽  
Richard C. van Loben Sels
Keyword(s):  
Body Size ◽  
Clutch Size ◽  
Egg Size ◽  
Reproductive Output ◽  
Body Sizes ◽  
Minimum Age ◽  
Average Size ◽  
Average Body ◽  
Clutch Mass ◽  
Growth And Reproduction

Growth and reproduction in Blanding's turtles (Emydoidea blandingi) were studied in southeastern Michigan from 1975 through 1988. Average body sizes of both sexes of adults were similar; however, shapes of males were different from those of females. The average size of a group of females with a mean minimum age of 47 years was not significantly different from a younger group with a mean age of 21 years. Clutch size ranged from 3 to 19 ([Formula: see text], N = 280) eggs over 11 years. Clutch wet mass ranged from 60.4 to 183.4 g ([Formula: see text], N = 17), and relative clutch mass of nine females averaged 0.12. Clutch size, and to a lesser degree egg size, showed a significant positive relationship with body size, but not with age of females. Hatchlings averaged 31.0 mm in plastron length, 35.3 mm in carapace length, and 9.2 g in body wet mass. Differences in juvenile growth rates and age at sexual maturity appear to be the major cause of variation in body size of adult Blanding's turtles and the related reproductive output per clutch.

Sign in / Sign up

Export Citation Format

Share Document