scholarly journals Feeding habits, sexual dimorphism and size at maturity of the lizard Cnemidophorus ocellifer (Spix, 1825) (Teiidae) in a reforested restinga habitat in northeastern Brazil

2010 ◽  
Vol 70 (2) ◽  
pp. 409-416 ◽  
Author(s):  
GG. Santana ◽  
A. Vasconcellos ◽  
YEA. Gadelha ◽  
WLS. Vieira ◽  
WO. Almeida ◽  
...  

The feeding habits, the sexual dimorphism in size and sexual maturity of the actively foraging lizard Cnemidophorusocellifer were analysed in an area of a reforested Restinga habitat located in the municipality of Mataraca, along the northern-most coast of Paraíba State, Brazil. Seventy-five specimens of C. ocellifer were examined (46 males and 29Â females). Of this total, only 23 specimens had prey in their stomachs. The most frequent prey consumed items were orthopterans (50%), coleopterans (23.9%) and arachnids (10.9%); termites and insect larvae were less consumed (both with 2.2%). There were no significant differences observed between the numbers of prey consumed by either males or females. There were significant differences in SVL (snout-vent length) between the sexes, with males attaining larger SVL values. When the influence of SVL was removed from the analyses, sexual dimorphism in the form was still reflected in the head size of these lizards. Sexual maturity in females and males was attained with SVL of 42.2 and 49.0 mm respectively. Although no significant difference was observed between the SVL of the females and the number of eggs produced, there was a clear tendency for larger females to produce more eggs. The low structural complexity of the vegetation and the poor soil quality in the reforested restinga area examined does not furnish favourable habitat for insect and termite larvae, contributing to the marked differences in the diet of the population of C. ocellifer observed in the present study in relation to the diet of their conspecifics in undisturbed areas of restinga, cerrado and caatinga.

2019 ◽  
Vol 18 (1) ◽  
pp. 77-87
Author(s):  
Cristiana Ferreira-Silva ◽  
Samuel Cardozo Ribeiro ◽  
Edna Paulino de Alcantara ◽  
Robson Waldemar Ávila

Natural history of the rare and endangered snake Atractus ronnie (Serpentes: Colubridae) in northeastern Brazil. The habitat use, activity period, sexual dimorphism, morphological variation, reproduction and diet composition of this fossorial and nocturnal snake are reported. The snakes were captured between 2008–2014 in the Chapada do Araripe in northeastern Brazil, and were collected by active visual searches, as well as in pitfall traps with drift fences. Although females are larger than males, the males have longer tails, and scale counts differ between the sexes. Reproduction is seasonal, occurring during the rainy season. Brood sizes rang from one to four eggs. Atractus ronnie preys on earthworms, in addition to ants (Crematogaster sp.) and insect larvae.


Crustaceana ◽  
2016 ◽  
Vol 89 (10) ◽  
pp. 1115-1124 ◽  
Author(s):  
René Zambrano ◽  
E. Alberto Aragón-Noriega

Sexual dimorphism was established in Ucides occidentalis (Ortmann, 1897) in the Gulf of Guayaquil, Ecuador on the basis of the size and dimensions of the chelar propodus (CP); whether the CP can be used as an indicator of sexual maturity in males was also evaluated. Morphological differences were also established in individuals by inspecting CP variability. Morphotypes were identified as homochelous (HmC, having a similar CP) or heterochelous (HtC, having one CP larger than the other), and varieties were established by the differences in the CP dimensions of each morphotype. The Kruskal-Wallis test was used to determine whether significant size differences based on the length and height of the major chelar propodus for each morphotype exist between the sexes. The largest sizes were determined in males (), and there was a significant difference () in length and height when the males of each morphotype were compared. This study established that U. occidentalis exhibits allometric CP growth, because the small sizes in successive molts do not allow the observation of evident differences between the developmental stages (juveniles and adults). Therefore, sexual maturity cannot be estimated in males using the CP, and it is necessary to use other structures (e.g., the pleopods) or methodologies (e.g., physiological) to estimate sexual maturity.


2013 ◽  
Vol 103 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Lucas R. P. Paschoal ◽  
Fernanda J. Guimarães ◽  
Erminda C. G. Couto

This study comprises the description of relative growth and sexual maturity of a population of Palaemon pandaliformis Stimpson, 1871 in Salsa River (Northeastern Brazil). Samples were collected monthly between September 2009 and August 2010. Females were larger, heavier, and showed a greater allometric coefficient (b) than male specimens. Only carapace length vs. pleura length in females presented a significant difference in the relative growth pattern, indicating a puberty moult. This relationship is strictly correlated to reproduction and its success rate in female shrimps. Estimated carapace length in 50% of mature females (CL50) was 4.53 mm. It was not possible to compare obtained CL50 results due to a lack of studies on this species. Comparison was based on the size of the smallest captured ovigerous female (3.81 CL mm), which is within the scope of recorded size for estuaries located in higher latitudes. This study reveals the lack of research on this genre in freshwater environments on a national and global scale.


2020 ◽  
Vol 655 ◽  
pp. 227-240
Author(s):  
KR Flanders ◽  
ZH Olson ◽  
KA Ono

Increasing grey seal Halichoerus grypus abundance in coastal New England is leading to social, political, economic, and ecological controversies. Central to these issues is the foraging ecology and diet composition of the seals. We studied grey seal feeding habits through next-generation sequencing of prey DNA using 16S amplicons from seal scat (n = 74) collected from a breeding colony on Monomoy Island in Massachusetts, USA, and report frequency of occurrence and relative read abundance. We also assigned seal sex to scat samples using a revised PCR assay. In contrast to current understanding of grey seal diet from hard parts and fatty acid analysis, we found no significant difference between male and female diet measured by alpha and beta diversity. Overall, we detected 24 prey groups, 18 of which resolved to species. Sand lance Ammodytes spp. were the most frequently consumed prey group, with a frequency of occurrence (FO) of 97.3%, consistent with previous studies, but Atlantic menhaden Brevoortia tyrannus, the second most frequently consumed species (FO = 60.8%), has not previously been documented in US grey seal diet. Our results suggest that a metabarcoding approach to seal food habits can yield important new ecological insights, but that traditional hard parts analysis does not underestimate consumption of Atlantic cod Gadus morhua (FO = 6.7%, Gadidae spp.) and salmon Salmo salar (FO = 0%), 2 particularly valuable species of concern.


2014 ◽  
Vol 2 (1) ◽  
pp. 23-27
Author(s):  
B Sharma ◽  
N Balaji ◽  
MK Sumathi

Background and objectives: Identification, an aspect of forensic anthropology, is the recognition of an individual based on the physical characteristics unique to the individual. Among the four main attributes i.e. gender, age, stature and ethnic or racial background of an individual’s biological identity, sex determination is usually the first step in the human identification process. Teeth can be used as a means of sex determination as teeth are resistant to post-mortem degradation and survive deliberate, accidental or natural change. This study was carried out with an objective to determine the sexual dimorphism of maxillary and mandibular canine by linear tooth diameter for permanent dentition in Moradabad population. Material and Methods: A total number of 40 subjects (20 Males and 20 Females) were included in this study. After obtaining an informed written consent, alginate impression was taken with help of perforated impression trays and study models were prepared with type IV dental stone. Linear (MD, BL, Crown Height) were taken with digital vernier caliper. Results: It was observed that males’ shows more mean linear crown diameter as compared to females. Also, the mesiodistal and buccolingual measurement shows statistically significant difference for all canines, being higher for males than females. Conclusion: The present study has expressed sexual dimorphism of permanent canine using Student’s test and indicate that linear dimension of maxillary canine can be used for sexual diamorphism with accuracy along with other accepted procedure for sex determination. DOI: http://dx.doi.org/10.3126/jmcjms.v2i1.11392   Janaki Medical College Journal of Medical Sciences (2014) Vol. 2 (1): 23-27


2008 ◽  
Vol 68 (3) ◽  
pp. 611-615 ◽  
Author(s):  
LA. Anjos ◽  
WO. Almeida ◽  
A. Vasconcellos ◽  
EMX. Freire ◽  
CFD. Rocha

From January to April 2006, 37 specimens of Hemidactylus mabouia were collected in houses, in the municipality of Barbalha (7° 20' S and 39° 18' W), Ceará State, Northeast Brazil. Among the individuals captured, 17 were infected with pentastomids, totalling a prevalence of 45.9%, which did not differ between sexes. Host size did not influence the infection intensity. Two species of pentastomids were found: Raillietiella frenatus and R. mottae. The prevalence of R. frenatus (43.2%) was higher than R. mottae (2.7%), whereas the infection intensity of R. frenatus was comparatively lower (1.8 ± 1.4) than R. mottae (36 parasites in a single host). Overall mean intensity of infection was 3.8 ± 8.4 pentastomids. We found no pentastomid infecting juvenile geckos. The parameters of infection in this host population are in accordance to the findings of other studies, in which the high parasitism rate was associated to the feeding habits of geckos living in houses and buildings. Hemidactylus mabouia is a new host to R. mottae and the infection by R. frenatus is the first record of the occurrence this pentastomid species in Brazil.


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Bhaskara Canan ◽  
Wallace Silva do Nascimento ◽  
Naisandra Bezerra da Silva ◽  
Sathyabama Chellappa

This study investigated the morphohistology of the digestive tract and the mean intestinal coefficient of the damsel fishStegastes fuscuscaptured from the tidal pools of Northeastern Brazil. The wall of the digestive tract ofS. fuscusis composed of the tunica mucosa, tunica muscularis, and tunica serosa. The esophagus is short with sphincter and thick distensible wall with longitudinally folded mucosa. Mucous glands are predominant, and the muscular layer of the esophagus presented striated fibers all along its extension. The transition region close to the stomach shows plain and striated muscular fibers. Between the stomach and intestine, there are three pyloric caeca. The intestine is long and thin with four folds around the stomach. The anterior intestine presents folds similar to those of pyloric caeca. The estimated mean intestinal coefficient and characteristics of the digestive system ofS. fuscuspresent morphological adequacy for both herbivorous and omnivorous feeding habits.


2014 ◽  
Vol 86 (1) ◽  
pp. 147-158 ◽  
Author(s):  
PAULO V. OLIVEIRA ◽  
ANA MARIA RIBEIRO ◽  
ÉDISON V. OLIVEIRA ◽  
MARIA SOMÁLIA S. VIANA

This paper deals with xenarthrans osteoderms assigned to Dasypus aff. D. novemcinctus, Euphractus sexcinctus and Cabassous sp. The material was collected in subsurface, from 0.10 to 0.60 m in the Urso Fóssil Cave, Parque Nacional de Ubajara, State of Ceará, northeastern Brazil. The ages of sediment samples from levels 4 and 5 (depths of 0.40 and 0.50 m) were determined by thermoluminescence technique, and indicated ages of 8,000 and 8,200 years BP for each layer respectively. The presence in these layers of early Holocene xenarthrans taxa can contribute to the understanding of the biotic evolution of the northwest region of Ceará during the last 10,000 years. Two of the three identified taxa still occur in the region: Dasypus novemcinctus and Euphractus sexcinctus. The Dasypodidae fauna here reported includes animals with generalist feeding habits and current wide geographical distribution. It is suggested, therefore, that the climatic and environmental conditions in the early Holocene were very similar the actual ones, and that the absence of Cabassous may be conditioned to other factors, such as anthropogenic action and loss of habitat by fragmentation of the vegetation.


2014 ◽  
Vol 64 (4) ◽  
pp. 333-342 ◽  
Author(s):  
Marcos de Miranda Leão Leite ◽  
Cynthia Yuri Ogawa ◽  
Carla Ferreira Rezende ◽  
José Roberto Feitosa Silva

The relationship between weight and size of individuals can be used to evaluate the status of a population, which is particularly useful for natural populations that are being exploited. Ucides cordatus occurs on the Atlantic coast of the American continent, from Florida (USA) to Santa Catarina (Brazil). This species is economically very important, most of all in the Northeastern area of Brazil, as well as in the Dominican Republic and Suriname. The objective of this study was to analyze life phases (‘fattening’, ‘matumba’, ‘milk-crab’, ‘maturation’ and ‘walking’) by use of the weight-length relationships, as well as temporal variations in this condition factor for each sex of U. cordatus. For this purpose, individuals were sampled monthly for twenty-four months at the Jaguaribe River estuary, Ceará State, Northeastern Brazil. The relationship between total weight and cephalothorax width was established using regression analysis, adjusted by a power equation. The dynamics of the condition factor were analyzed for each sex using the variation of its averages related to annual life cycle; this was done for each of the previously-mentioned phases. The relationship between total weight and cephalothorax width showed an isometric growth in males and negative allometric growth in females suggesting that, for the same reference size, males are heavier than females. When considering the average of the female condition factors, these were greater than those for males during the annual life cycle, except during the ‘maturation’ phase, which is the phase with a higher demand of energetic reserves for males. Annual variation of the condition factor in females presented no significant difference.


2021 ◽  
Vol 8 (3) ◽  
pp. 147-152
Author(s):  
Mosmi Lomi ◽  
Jonathan Daniel M

Determining gender is one of the most important procedure in forensics. Teeth are made of the most enduring mineralized tissues in the body, as such, they have an extraordinary resistance to putrefaction and the effects of external agents (physical, thermal, mechanical, chemical or biological) which makes them invaluable material for anthropological, genetic, odontologic and forensic examinations.i)To assess the degree of sexual dimorphism in maxillary canine using maxillary canine index, maxillary first molar and central incisor using mesiodistal (MD) and buccolingual/buccopalatal (BL) dimensions of the crown. ii) To determine the accuracy of maxillary canine index, first molar and central incisor dimensions (mesiodistal and buccolingual/buccopalatal) in determining sex.This study consisted of total 30 participants (males=15, females=15) of age group ranging from 20 to 35 yrs. Measurement of dimensions of selected teeth were performed on maxillary cast using digital Vernier caliper, resolution 0.01mm. Data thus obtained were analyzed statistically.The mean values of all the measurements in males were greater than females. There was statistical significant difference in mean value of bucco-lingual width of molar, mesiodistal width of canine (on left side, right side and average) and the inter-canine distance between males and females. The buccolingual width of molar showed the highest % of sexual dimorphism (5.33%) and the mesiodistal width of molar showed the least % of dimorphism (0.7%). Bucco-lingual width of molar posed the highest prediction accuracy for gender determination. We conclude that buccolingual width of maxillary first molar can be used to predict the gender when only teeth of maxillary arch are available for forensic examination.


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