Acta Zoologica最新文献

Microscopy suggests that glutathione S-transferase is stored in large granules of myeloid cells in bone marrow and sparse granulocytes of the regenerating tail of lizard. Acta Zoologica (Stockolm). Tail regeneration in lizards occurs after an immune-privileged blastema and is formed where various immunosuppressive cells and biomolecules keep inflammation low. Molecules that limit inflammation may include glutathione and glutathione S-transferase (GST). These molecules reduce reactive oxidative species (ROS) and detoxify extraneous molecules. In the present study, the presence of GST has been analysed in the early phases of tail regeneration in the lizard Podarcis muralis. Using a rabbit polyclonal antibody directed against epitopes present in GST of P. muralis, a light and electron microscopy immunohistochemical and Western blotting study has been done. The study detected proteins of 25 and 32 kDa in pale-medium electron-dense and large granules present in promyelocytes and myelocytes of likely basophilic or eosinophilic fate that is present in the bone marrow of tail vertebrae. These cells are still proliferating and give rise to basophilic or eosinophilic granulocytes that also migrate into the regenerating tail. The enzyme stored in granules of promyelocytes and myelocytes is also localized in the cytoplasm of granulocytes present in the regenerating blastema-cone, basophilic or/and eosinophilic. It is suggested that these granulocytes in the blastema reduce ROS and detoxify potentially inflammatory metabolites, contributing with other molecules to limit inflammation and favour regeneration.

Brachyuran crabs are considered one of the most representative groups in mangroves, being recognised as mangrove engineers. However, species that present commercial interest may have their population structure and spatial distribution affected by human activities, such as crab capture. Therefore, monitoring populations over time is essential. We investigated the population biology, size-weight relationship, condition factor and spatial distribution of Ucides cordatus in a mangrove ecosystem from southern Brazil, providing information for population status assessment. Males and females differed in abundance and frequency, body size, size-weight relationship and condition factor. Nonetheless, they presented the same spatial distribution pattern. Abundance, sex ratio and body size also revealed a possible influence of anthropised areas in the configuration and distribution of the species. Our results indicate a possible increase in the exploitation of the species, mainly due to the decrease of the largest male size classes’ frequency. Interspecific competition seems to be a possible biotic factor influencing its condition factor. The spatial species distribution highlighted the importance of sites with less anthropogenic influence for the maintenance of the species that can be considered as key areas for the conservation of the U. cordatus in Babitonga Bay.

The obscure mealybug Pseudococcus viburni (Signoret) (Hemiptera: Pseudococcidae) is recorded for the first time from Colombia based on specimens collected on Opuntia cylindrica (Lam.) DC., Mammillaria sp. (Cactaceae), Escallonia paniculata (Ruiz & Pav.), Roem. & Schult. (Escalloniaceae), Ficus carica L. (Moraceae), Coffea arabica L. (Rubiaceae), Citrus sp. (Rutaceae), Cestrum nocturnum L. and Solanum betaceum Cavanilles (Solanaceae). Multiple methods were used to identify P. viburni because it belongs to the “Pseudococcus maritimus” complex, a group composed of more than 60 species with high variation in morphological characteristics. The specimens were identified based on the morphology and morphometric analysis of third-instar nymphs and adult females. This morphological identification was corroborated by data on geographical distribution, plant hosts and a molecular identification using two different loci, CO1 (mtDNA) and the 28S ribosomal gene (nuclear genome). An updated list of species of Pseudococcus Westwood recorded from Colombia and information on morphological variation found in the studied specimens from Brazil and Colombia are provided.

In the present work, the morphological characteristics of sagitta were described and analysed for 10 species of combtooth blennies (Blenniidae) inhabiting the intertidal region of the Persian Gulf and Makran zone of Oman Sea to see the taxonomic usefulness of otoliths, especially their hidden characters for species identification. Based on the obtained results, sagitta morphology could be considered as diagnostic characters distinguishing the genera Alticus, Antennablennius, Istiblennius, Omobranchus and Parablennius showing differences related to general shape, that is, elliptic/oval to triangular; shape of antirostrum and its degree of development; the degrees of convexity of ventral and dorsal margins, and shape of ostium. The common/general otolith characters shared in the all studied combtooth blennies, is the heterosulcoid condition, which is a shared character with Perciformes and Gobiiformes. The type of sulcus is ostial, and it can be considered as a plesiomorph character shared with a basal group of actinopterygian fishes. The obtained results could be useful in taxonomical, paleontological, ecological and food and feeding habits studies.

Population and reproductive information of highly endemic species allow us to understand their underlying conservation problems. Aegla concepcionensis is restricted to a small and intervened Chilean basin, and its conservation status has varied from extinct in nature to endangered. We characterized their life history measuring population, morphological and environmental variables during an annual cycle capturing individuals with a catch and release method based on electroshocking. Although the maximum water temperature was related to the recruitment, it can be physiologically risky for the remaining macroinvertebrate community. The relationship between abundance and narrow pH variations indicates a condition of unstable equilibrium given the environmental deterioration by deforestation. Sex ratio was predominantly male biased during copulatory activity, and sexually dimorphic body size distributions supported the hypothesis of greater natural selection in females and sexual selection in males. The period of ovigerous females was comparatively restricted, late and consistent with an efficient ecophysiological strategy of reproductive investment. Patterns of pubertal moult, onset of morphometric maturity, absence of morphological differentiation in both sexes suggested that A. concepcionensis tends to maximize reproductive performance favouring the recovery of their relict populations.

Helicoverpa armigera (Hübner) is one of the most prominent polyphagous species of the Heliothinae pest complex that inflicts severe damage to a wide range of crops in India. Knowledge regarding the population structure of the pest species, whether morphological or genetic, is considered as an essential tool in making effective management decisions. Thus here, we performed the phenotypic characterization of H. armigera populations collected from varied geographic locations across India. Studied populations differed significantly for several external morphometric traits studied at larval, pupal and adult stages. Significant differences were also observed with respect to the intensity of black pigmentation on larval body as well as adult eye and forewing colour patterns. Besides external phenotypic traits, the length of genital organs like aedeagus and valva in males, and bursa copulatrix and bursa seminalis in females also differed significantly amongst populations. The dendrogram based on selected traits showed clear cut differentiation of studied populations into two major groups, one including all the South Zone populations and the other having populations from North and Central Zones. Differences based on phenotyping in the present study indicate the possibility of the existence of different subspecies within the Indian populations of H. armigera.

The histological and histochemical studies of gastrointestinal tract (GI tract) are important for understanding the morphophysiology in animal digestive processes. Therefore, this study aimed to describe and analyse the histological and histochemical characteristics of Varanus salvator GI tract based on two adult wild-caught specimens (male and female). The results of histological study revealed that most of V. salvator GI tract is quite similar to that of other vertebrates. However, only slight differences were found in some histological aspects. According to the fine structure of stomach, the oxynticopeptic cells of oral fundic region contained numerous secretory granules, while those of the aboral fundic region contained less secretory granules. For the mucin histochemical study, the acid and neutral mucins can be found throughout the GI tract except for pyloric stomach found neutral mucin only. This study provides information about the microanatomic structures of V. salvator GI tract that could be applied to the biological and veterinary sciences, and farming and feeding management.

In Squamate reptiles, vitellogenesis in females is marked by an increase in the number and size of follicles, leading to an increase in aerobic metabolism to support the rising energy demand during reproductive activity. Male gametes are smaller than female gametes, and spermiogenesis requires less energy than vitellogenesis. This investigation compares the relationship between aerobic metabolism and reproductive effort in male and female viviparous Tomodon dorsatus snakes. We evaluated the influence of the males' and females' reproductive stages, along with the masses of follicles and testicles, on their aerobic metabolic rate. Our findings show that females have higher maintenance cost of pregnancy than metabolic costs of vitellogenesis. In males, we found no evidence of the reproductive effort influencing aerobic metabolic rates. In T. dorsatus, females have a long period of development and high fecundity. Therefore, the metabolic costs of vitellogenesis represent a critical component in the reproductive effort. On the other hand, males of T. dorsatus maintain a similar mass of gonads throughout the year with constant energy demand. These results reflect the difference in reproductive efforts between females and males of T. dorsatus.

The abdominal and pregenital segments and genitalia were studied in males of Tachina nupta Rondani, 1859. The examined species is very similar in the structure of the sclerites and muscles of their terminal segments to Calliphora erythrocephala Meigen, 1826 previously studied by R. Salzer. Despite the same set of pregenital muscles, a completely membranous tergite VI was found in Tachina in contrast to Calliphora. The discovery of membranous tergite VI in Tachina nupta indicates that it was not included in the syntergosternite VII +VIII. The membranous tergite VI, as well as the reduced set of muscles of the phallapodeme (absence of muscles of postgonites) in Tachina compared with Calliphora, indicates the result of apomorphic reduction in Tachina. Descriptions and figures of the genital sclerites and muscles of Tachina nupta are given.