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The Amazon rainforest represents nearly 40
‘Turiaçu’ is a pineapple variety native to the Amazon region with high commercial potential that remains unexplored. Its propagation traditionally relies on vegetative material from mother plants, which increases the risk of pathogen transmission. Temporary immersion bioreactors (TIBs) are an alternative for large-scale production of disease-free plantlets, but their efficiency depends on the optimization of culture conditions. This study aimed to evaluate the effects of photoautotrophic and photomixotrophic in vitro cultivation of ‘Turiaçu’ pineapple under different light intensities in TIBs, as well as the subsequent ex vitro acclimatization performance of the plants. Explants were cultivated under light intensities of 71 and 116 µmol m⁻² s⁻¹, in culture media containing 0–15 g L⁻¹ of sucrose. After 50 days of in vitro growth, biometric parameters, photosynthetic pigments, gas exchange, and leaf anatomy were evaluated. Following 30 days of ex vitro acclimatization, survival, growth, and physiological performance were analyzed. The presence of sucrose in the culture medium was the main factor influencing growth and photosynthetic performance. Photoautotrophic conditions stimulated photosynthetic capacity, whereas photomixotrophic cultivation promoted greater biomass accumulation, particularly under 71 µmol m⁻² s⁻¹. Both cultivation modes resulted in 100
The fish fauna of the basin of the Amazon River is one of most diverse of any region on Earth and hosts a parasite fauna that is poorly studied. One group of fish parasites is the Myxosporea, a class of the phylum Cnidaria, which are obligate endoparasites. The present study investigated myxozoans found in specimens of the Neotropical catfish Ageneiosus inermis collected in Marajó Bay, off Humaitá Beach. A total of 25 A. inermis specimens were captured and anaesthetised for necropsy, including the gallbladder, liver and muscle tissue, which were prepared for light microscopy, molecular biology and histology. Plasmodia and spores with morphology typical of the genus Ellipsomyxa were observed in the gallbladders of 14 of the individuals. The disporic plasmodia contain two mature spores measuring 6.6 μm × 4.0 μm, on average, with subterminal polar capsules. The analysis of a partial sequence of the 18 S rDNA gene, together with the morphological and morphometric characteristics of the specimens, supported conclusively the description of a new species of the genus Ellipsomyxa. This is the first record of a species of this genus parasitising A. inermis. This represents the first record of a species of this genus parasitizing A. inermis and describes a new taxon.
The Amazon biome hosts a rich diversity of reptile species, including Boa constrictor (Linnaeus, 1758), widely distributed throughout Brazil and belonging to the order Squamata. Despite its ecological importance, detailed descriptions of lingual morphology in this species remain limited. This study aimed to describe the tongue of B. constrictor using macroscopic, histological, and scanning electron microscopy (SEM) analyses. Four specimens obtained post mortem after road accidents were analyzed. It is important to consider that freezing and thawing procedures may have influenced tissue preservation. Macroscopically, the tongue is elongated, bifurcated, and smooth, with no visible papillae or median groove. However, SEM revealed a median groove in the body of the tongue. Histologically, the tongue is lined by stratified squamous epithelium with slight keratinization, supported by connective tissue and skeletal muscle bundles. No papillae, taste buds, or salivary glands were observed under the conditions of this study. These findings support the sensory role of the tongue in snakes and contribute to comparative anatomical knowledge.
Rays of the family Rhinopteridae Jordan Evermann, 1896 are highly migratory and widely distributed in warm tropical and temperate waters. Along the Brazilian coast, the presence of two species has been recorded: Rhinoptera bonasus Mitchill, 1815 and Rhinoptera brasiliensis Müller, 1836. These stingrays are commonly caught as bycatch in trawl fisheries, however, the two species lack distinctive external morphological features that allow for reliable differentiation—species identification is primarily based on the shape and arrangement of teeth in the buccal plates. This study aimed to investigate the evolutionary history of the genus Rhinoptera and to explore which evolutionary drivers, such as biogeographic events or behavioral traits, have influenced its diversification. To achieve this, we analyzed both mitochondrial and nuclear genetic markers, focusing on the species occurring along the Brazilian coast. Specimens of both species were collected across various locations in Brazil, and additional sequences from other Rhinoptera species were obtained from GenBank. Our results reveal the presence of multiple cryptic species within Rhinoptera, particularly within R. bonasus, and likely in Rhinoptera steindachneri Evermann Jenkins, 1891 and Rhinoptera javanica Müller Henle, 1841. Notably, R. bonasus does not occur in Brazilian waters nor in parts of the Caribbean where a distinct cryptic sister lineage was identified. Based on our findings, we propose the resurrection of Rhinoptera lalandii Müller Henle, 1841 as the species representing the lineage found along the Brazilian coast and the Eastern Atlantic Ocean. We suggest that philopatric behavior may represent one of several factors potentially influencing diversification within Rhinopteridae, although this hypothesis requires direct behavioral and population level validation. These findings highlight the urgent need for a comprehensive taxonomic revision of the family, as well as a reassessment of current conservation strategies to better reflect the hidden diversity within this group of species.
