Young Specimens Research Articles

Growth patterns and age determination of Piked Dogfish from Romanian Black Sea waters: Insights from spines analysis

Understanding the growth patterns and the age composition of Squalus acanthias (piked dogfish) populations, from Romanian marine area, helps to elaborate sustainable fisheries management practices because changes in population parameters could indicate shifts in prey availability, habitat quality issues, or fishing pressure. In recent years, the official catches on the Romanian coast, of this economically valuable species in the entire Black Sea basin, have remained below one ton. Regarding the growth patterns, a slight increase in the average length value was observed, from 107,85 cm in 2022 to 116,88 cm in 2023. For age determination the method of analyzing the dorsal spines was used, considered the most appropriate. Thus, in 2022 mature specimens (19 years old) predominated, and in 2023, younger specimens (14 years old), but completely mature from a reproductive point of view, predominated. Analyzing age structure over time is important for predicting future population trends and implementing conservation measures as needed.

MYCOFLORAL ANALYSIS OF AGARICS AND MEDICINAL MUSHROOMS DISTRIBUTED IN THE BOROVOE AND KOKSHETAU NATIONAL PARKS

The article provides a literature review of mycofloral analysis of agarics and medicinal mushrooms distributed in the Borovoe and Kokshetau national parks. As a result of the literature review, 15 species of fungi belonging to 4 genera and 9 genera of the genus Agaricales were identified. Of these, edible -5, inedible – 3, poisonous – 1 species. Collection of Macromycetes during the expedition was collected by route method from Borovoe and Kokshetau national parks. The collection, sorting, drying, packaging and transportation of the collected material was carried out in accordance with the methods of mycology and Botany. 30-40 min at 45-50° t for the purpose of disinfection of the collected samples. in between, a heating cabinet (water heater) was used. Each processed sample is stored in a specially designed box with the date, place, time of collection and herbarium number. The external morphological description of the fruiting body of the fungus was made by visual observation, and for determining the microscopic structure, features of spores, we used the Mikmed-1 microscope and cameras connected to it Exilim-S880, SAMSUNG-ES65, Canon-PC1474. To separate the tissue particle from the fruit body of the fungi, a fertile, non-darkening, young specimen was obtained. A cube-shaped or triangular pyramidal "tissue" particle was cut out of the pre-cleaned fruit bodies through a scalpel and planted in a nutrient medium (oblique agar) through an inoculation needle. Isolation was carried out from different parts of the fruit body: caps, legs, places of transition of the cap to the stem. The growth and development of the selected clean crop will depend on the composition of the nutrient medium. The cortical medium we used was diverse, including "Chapeka–Doxa", "Murashige Skuga" and potato-glucose agar. As a result of the study, more than 25 mushroom samples were collected. As a result, 15 species from 9 relatives from 4 genera belonging to the family of cap mushrooms Agaricales were identified. 4 genera have been identified in the agaricales series: Agaricaceae, Russulaceae, Tricholomataceae, Strophariaceae. As a result of summing up the results of the conducted research, we came to the following conclusions: During the study, the characteristics of morphological forms of fungi were developed. Based on the obtained morphometric characteristics, the species of fungi were determined using special determinants. As a result of studying all the collected mushrooms in the Kokshetau and Borovoe National parks, 15 species of fungi from 9 genera belonging to the genus Agaricales were identified. Of these, 1 is poisonous, 5 is edible, and 3 are inedible. A species synopsis of Agaricales fungi in the Kokshetau and Borovoe National parks has been compiled. All the results and data obtained are of great importance for the effective use of natural resources and their protection.

David versus Goliath: An interspecific comparison between small-sized Halicryptus spinulosus and large-sized Halicryptus higginsi (Priapulida)

Halicryptus includes two priapulid species with highly different adult body sizes, small-sized Halicryptus spinulosus von Siebold, 1849 and large-sized Halicryptus higginsi Shirley and Storch, 1999. Due to ambiguity of diagnostic characters from juvenile to adult size and between species, a detailed morphological and molecular comparison is needed to resolve the distribution and characteristics of each species. We investigate an adult paratype specimen of H. higginsi, and young adult specimens of H. spinulosus from the Beaufort Sea and H. spinulosus from Kandalaksha Gulf, White Sea. Molecular analysis of the mitochondrial CO1 gene confirm the existence of two species of Halicryptus, a wide distribution of H. spinulosus across the Northern Hemisphere and the co-occurrence of both species in the Beaufort Sea. Our morphological analyses reveal undocumented characters for Halicryptus, such as the presence of three different sizes of buccal papillae, scattered small trunk papillae, and a loose ring of flosculus-tubulus-complexes on the posterior trunk. For both species, we revise characters, such as the number of long introvert retractors, pharynx protractors and lateral cusps of anterior teeth, and the maximum number of scalids in a row in H. spinulosus. We propose a total of ten reliable and potential diagnostic characters distinguishing the two species and revise the terminology of Halicryptus-specific characters due to inconsistency in the literature. In addition, we discuss the effect of body size on selected morphological traits.

The Effects of Unitizing Nail-Plate Constructs in Distal Femur Fractures: A Biomechanical Study.

To assess the biomechanical differences between linked and unlinked constructs in young and osteoporotic cadavers in addition to osteoporotic sawbones. Intraarticular distal femur fractures with comminuted metaphyseal regions were created in three young matched pair cadavers, three osteoporotic matched pair cadavers, and six osteoporotic sawbones. Precontoured distal femur locking plates were placed in addition to a standardized retrograde nail, with unitized constructs having one 4.5 mm locking screw placed distally through the nail. Nonunitized constructs had seven 4.5 mm locking screws placed through the plate around the nail, with one 5 mm distal interlock placed through the nail alone. Cadaveric specimens were subjected to axial fatigue loads between 150 and 1500 N (R Ratio = 10) with 1 Hx frequency for 10,000 cycles. Sawbones were axially loaded at 50% of the ultimate load for fatigue testing to achieve runout, with testing performed with 30 and 300 N (R Ratio = 10) loads with 1 Hz frequency for 10,000 cycles. In young cadavers, there was no difference in the mean cyclic displacement of the unitized constructs (1.51 ± 0.62mm) compared to the non-unitized constructs (1.34 ± 0.47mm) (Figure 4A), (p = 0.722). In osteoporotic cadavers, there was no difference in the mean cyclic displacement of the unitized constructs (2.46 ± 0.47mm) compared to the non-unitized constructs (2.91 ± 1.49mm) (p =0.639). There was statistically no significant difference in cyclic displacement between the unitized and non-unitized groups in osteoporotic sawbones(p = 0.181). Linked constructs did not demonstrate increased axial stiffness or decreased cyclical displacement in comparison to unlinked constructs in young cadaveric specimens, osteoporotic cadaveric specimens, or osteoporotic sawbones.

Otolith morphology of mesopelagic fishes collected from the Irminger Sea, North Atlantic Ocean

A large series of otoliths of 16 mesopelagic teleost fish species from the Irminger Sea, North Atlantic Ocean, are described morphologically to investigate the ontogenetic and intraspecific variation. The results show that the surface morphology of the otoliths between young and adult specimens is variable, especially in the alepocephaliform (Normichthys operosus, Sagamichthys schnakenbecki, Xenodermichthys copei) and astronesthine (Borostomias antarcticus) species. The diagnostic features of the otoliths can be used to confirm the identity of the species, especially in myctophids, where confusion between Benthosema glaciale and Myctophum punctatum may be possible. A SEM-based iconography of the otoliths of all studied species is presented.

Phalacrocorax bakonyiensis n. sp., a new species of cormorant from the Late Miocene of Hungary

Abstract We describe Phalacrocorax bakonyiensis n. sp. an extinct member of the cormorants (Phalacrocoracidae). The fossil was found in 2021 by geologist János Futó in the sediments of a small cave cavity on the side of Várhegy in Sümeg, a part of the Bakony Mountains of West Hungary, where Late Miocene (MN11–12) vertebrate fossils have been found in the past decades. The total number of bone fragments collected was 14, of which only three can be identified. Two of these belong to adults and one, due to its poor preservation and size, to a very young specimen.

Analyzing Pelvic Asymmetry by Sex and Ancestry: Insights From an Osteological Collection.

Pelvic asymmetry has been noted in pelvic imaging, and might influence the development of various spinal pathologies, most notably scoliosis. There is a limited understanding of the relationship between pelvic asymmetry and sex and ancestry, and limited use of 3D modeling. The purpose of this study was to identify pelvic asymmetry and morphology differences between sex and ancestry utilizing 3D modeling on young adults in an osteological collection. Thirty-three osteological pelvic specimens aged 18-25 years (average age 21.4 ± 2.0 years) were scanned to create virtual 3D models for analysis. Pelvic asymmetry and morphology were measured and compared across sex (male and female) and ancestry (European American and African American). Multivariate regression analysis was performed to examine the relationship between the variables measured. Multivariate regression analysis demonstrated statistically significant relationships between innominate-pelvic ring ratio and both sex (p < 0.001) and ancestry (p= 0.003) with larger ratios in male and African American specimens respectively. There was also a statistically significant relationship of greater sacral 1 coronal tilt in European American specimens (p= 0.042). There were no statistically significant differences with sex or ancestry in terms of innominate or sacral asymmetry. Although there are differences in overall pelvic shape between sex and ancestry, there is no relationship between these two variables versus pelvic asymmetry in the axial or sagittal planes in young adult osteological specimens.

Syagrus coronata fixed oil prevents rotenone-induced movement disorders and oxidative stress in Drosophila melanogaster

ABSTRACT One prominent aspect of Parkinson’s disease (PD) is the presence of elevated levels of free radicals, including reactive oxygen species (ROS). Syagrus coronata (S. coronata), a palm tree, exhibits antioxidant activity attributed to its phytochemical composition, containing fatty acids, polyphenols, and flavonoids. The aim of this investigation was to examine the potential neuroprotective effects of S. coronata fixed oil against rotenone-induced toxicity using Drosophila melanogaster. Young Drosophila specimens (3–4 d old) were exposed to a diet supplemented with rotenone (50 µM) for 7 d with and without the inclusion of S. coronata fixed oil (0.2 mg/g diet). Data demonstrated that rotenone exposure resulted in significant locomotor impairment and increased mortality rates in flies. Further, rotenone administration reduced total thiol levels but elevated lipid peroxidation, iron (Fe) levels, and nitric oxide (NO) levels while decreasing the reduced capacity of mitochondria. Concomitant administration of S. coronata exhibited a protective effect against rotenone, as evidenced by a return to control levels of Fe, NO, and total thiols, lowered lipid peroxidation levels, reversed locomotor impairment, and enhanced % cell viability. Molecular docking of the oil lipidic components with antioxidant enzymes showed strong binding affinity to superoxide dismutase (SOD) and glutathione peroxidase (GPX1) enzymes. Overall, treatment with S. coronata fixed oil was found to prevent rotenone-induced movement disorders and oxidative stress in Drosophila melanogaster.

Helminth infection in wild boars in Primorye, Russia

Wild boars have a worldwide distribution and also have major economic, veterinary, and medical importance. Due to a small amount of data on the parasitic fauna of wild boars in the Russian Far East, especially in Prymorye territory, a post-mortem parasitic examination of 20 wild boars was provided. The general prevalence was 25%, and a total of six helminth species, including one larva stage, were found. The most prevalent helminth species were Gnathostoma doloresi (25%) and Metastrongylus elongatus (20%). Followed by Trichuris suis and Ascaris suum (15%). The lowest prevalence was registered for Cysticercus tenuicollis (the larvae stage of T. hydatigena). Parasites were found in each region, with the highest prevalence registered in the Chuguevskii region. Totally 100% of adult boars were positive for helminth infections, instead of 60% of young specimens. Some helminthes found (G. doloresi, T. suis, A. suum) have zoonotic potential and can be involved in the circulation of human parasitic diseases, especially in rural areas. Further research work on parasitic infections in wild boars in Prymorye is necessary due to the high prevalence of helminthes in wild boars.

Palaeontological and taphonomical investigations of the exceptionally rich concentration of Miocene vertebrate coprolites from Pécs-Danitzpuszta (Hungary, Mecsek Mts.)

ABSTRACT Thousands of coprolites have been collected from the Upper Miocene (Tortonian/Pannonian) sands of the Pécs-Danitzpuszta sand pit, one of the most important mixed Neogene vertebrate localities in Hungary. Although, the locality has been known for centuries, the coprolites have not been investigated in detail. We describe these fossils and explore their palaeoecological significance. Coprolites were examined with thin sections, X-ray powder diffraction and computed tomography. Their surface is mostly smooth, desiccation cracks were not observed. All coprolites mainly consist of apatite, indicating most probably a carnivorous diet. No evidence of herbivory has been found so far. The coprolites contain remains belonging to several groups: ostracod carapaces, bivalve shells, vertebrae from bony fishes, fish scales, as well as teeth. The CT scans show inhomogeneities in the matrix; however, in most cases they do not reliably indicate inclusions. The taphonomical features suggest rapid burial and most likely an aquatic origin. The spiral morphotype could be attributed to fishes with spiral intestinal valves. Teeth of reef-associated fish taxa indicate Badenian age for some specimens, though the coprolite assemblage might include older and younger specimens as well.

Vascular plants and mosses as bioindicators of variability of the coastal pine forest (Empetro nigri-Pinetum)

Empetro nigri-Pinetum is a unique sea coast plant community developing along the Baltic Sea from Germany to Lithuania. Our detailed field research of bryophytes and vascular plants has highlighted the regional diversity of the Empetro nigri-Pinetum typicum plant community throughout its range in Central Europe. Our study indicated that vascular plants and mosses effectively discriminate against the described phytocoenoses, thus it was possible to distinguish three variants of the coastal forest: Calluna–Deschampsia (from Germany), Vaccinium vitis–idaea (from Poland) and Melampyrum–Deschampsia (from Lithuania). Redundancy analysis indicated that the division is related to the habitat conditions of the analyzed areas, with humidity having the greatest impact on this differentiation. Kohonen’s artificial neural network (i.e. self-organising map, SOM) confirmed the heterogeneous nature of the studied phytocenoses, and combined with the IndVal index enabled identification of indicator species for respective studied patches: Deschampsia flexuosa for Calluna–Deschampsia group; Aulacomnium palustre, Calluna vulgaris, Carex nigra, Dicranum polysetum, Erica tetralix, Oxycoccus palustris, Sphagnum capillifolium, Vaccinium uliginosum and Vaccinium vitis–idaea for Vaccinium vitis–idaea group; and young specimens of Betula pendula, Lycopodium annotinum, Melampyrum pratense and Orthilia secunda for Melampyrum–Deschampsia group. Thereby, our study showed that individual groups of species can be very good bioindicators for each of the studied phytocoenoses.

Phylloporia mutabilissp. nov. from Benin, West Africa.

Phylloporia is a widespread genus of Hymenochaetales (Basidiomycota) with polyporoid basidiomata found mainly in the tropics. Species of Phylloporia are predominantly parasitic of woody plant hosts, while some species grow as saprotrophs. Data on the genus is still scarce for tropical Africa, where we expect a high diversity given the high plant diversity in this area. Two specimens of this genus were collected in Benin (West Africa) and analysed morphologically and phylogenetically based on a multigene dataset (ITS, LSU, EF1α). Strong support for a species new to science was found, described here as Phylloporia mutabilis. It differs from other Phylloporia species by stipitate, coriaceous basidiomata, earth coloured to dark brown when fresh and changing upon drying from golden to yellowish brown, the margin being large in young specimens, becoming narrower with maturity. Basidiomata of Phylloporia mutabilis grow on the soil under angiosperm trees in a dense dry forest, so its lifestyle (saprotrophic, parasitic or mycorrhizal) is not evident, and future ecological studies will be required to elucidate this aspect. Citation: Olou BA, Krah F-S, Piepenbring M, Yorou NS (2023). Phylloporia mutabilis sp. nov. from Benin, West Africa. Fungal Systematics and Evolution 12: 81-89. doi: 10.3114/fuse.2023.12.06.

Retrieval of long DNA reads from herbarium specimens.

High-throughput sequencing of herbarium specimens' DNA with short-read platforms has helped explore many biological questions. Here, for the first time, we investigate the potential of using herbarium specimens as a resource for long-read DNA sequencing technologies. We use target capture of 48 low-copy nuclear loci in 12 herbarium specimens of Silene as a basis for long-read sequencing using SMRT PacBio Sequel. The samples were collected between 1932 and 2019. A simple optimization of size selection protocol enabled the retrieval of both long DNA fragments (>1 kb) and long on-target reads for nine of them. The limited sampling size does not enable statistical evaluation of the influence of specimen age to the DNA fragmentation, but our results confirm that younger samples, that is, collected after 1990, are less fragmented and have better sequencing success than specimens collected before this date. Specimens collected between 1990 and 2019 yield between 167 and 3403 on-target reads > 1 kb. They enabled recovering between 34 loci and 48 (i.e. all loci recovered). Three samples from specimens collected before 1990 did not yield on-target reads > 1 kb. The four other samples collected before this date yielded up to 144 reads and recovered up to 25 loci. Young herbarium specimens seem promising for long-read sequencing. However, older ones have partly failed. Further exploration would be necessary to statistically test and understand the potential of older material in the quest for long reads. We would encourage greatly expanding the sampling size and comparing different taxonomic groups.

Ontogenetic skull variation in a shovel-headed amphisbaenian species.

Leposternon microcephalum is a species belonging to the Amphisbaenia, a group of burrowing reptiles. Amphisbaenia present various morphological and physiological adaptations that allow them to penetrate the ground and live underground, through a system of galleries and permanent chambers that they build themselves. Among the morphological adaptations in this group, those of the skull stand out as it serves as the main excavation tool. Four basic skull shapes are recognized: rounded, keeled, shovel-shaped, and spade-shaped. The skull of L. microcephalum belongs to this last type, which is considered the most specialized. The species inhabits soils that are highly compacted and difficult to penetrate. Among the species of Leposternon present in South America, L. microcephalum has the widest distribution, being found in all Brazilian biomes and neighboring countries such as Bolivia, Argentina, Paraguay, and Uruguay. The analysis of the skull of this species was carried out using three-dimensional geometric morphometrics (3D-GMM), a technique that allows comparative analysis, through robust statistical methods, of shape and its variations, using Cartesian coordinate data from a configuration of homologous landmarks. The technique allows the size and shape components of a structure to be analyzed separately. From an ontogenetic point of view, this methodology had also been used to investigate variations in Cynisca leucura, a member of the Amphisbaenidae with a rounded head. Our hypothesis is that the patterns of morphological differentiation in the skull, mainly in the intermediate and occipital regions, are similar in different Amphisbaenia species. Therefore, the objective of this study was to analyze cranial morphological variations in an ontogenetic series of L. microcephalum using 3D-GMM. Computed Tomographic scans of 13 specimens were analyzed: juveniles (N = 8) and adults (N = 5), based on 20 landmarks that characterize the skull. Principal components and regression analyses between shape (dependent variable) and size (independent variable) showed a clear difference between the cranial morphological pattern of juvenile individuals and that of adults. For instance, young specimens tend to have a dorsoventrally tall neurocranium, with the tip of the snout more anteriorly oriented and its dorsal border subtly curved. Dorsally, the parietal region is thicker and smoothly dome-shaped in juveniles. As in C. leucura, the variation was strongly correlated with the size change from juvenile to adult, indicating a dominant role for ontogenetic allometry in determining skull shape.

Sustainability of tunas and swordfish exploitation in the equatorial tropical Atlantic Ocean

Fishing is important as it generates employment, income, high-quality food and livelihoods for native communities in many parts of the world. However, when poorly managed, it can cause irreversible overfishing impacts on the ecology of communities. The present study aimed to construct models to estimate the presence probability of young specimens of Thunnus albacares, Thunnus obesus and Xiphias gladius in the Western Equatorial Tropical Atlantic Ocean (WETA) using oceanographic, temporal, and spatial variables. The data used were generated by monitoring the fishing operations of vessels of the pelagic longline fleet in the extreme northeast of Brazil. The Generalized Additive Model was used to estimate the effect of different factors and covariates (oceanographic, temporal, and spatial variables) on the juvenile probability of the presence of the species T. albacares, T. obesus and X. gladius. The capture of juveniles becomes graver in the results obtained annually, for T. albacares ranged between 12.4% and 50.5%, T. obesus ranging from 27.5% to 36.4% and X. gladius from 0% to 13.8% immatures. Models established indicated that water temperature, year, longitude, chlorophyll-a and the interactions between moon phases and latitude, as well as the interactions between quarters and latitude, are statistically significant, influencing the distribution of juveniles of these resources. More efforts and attention should be directed to investigating the distribution of juvenile presence in the WETA, mainly in the southern hemisphere. We want to initiate here a broad discussion and campaign for establishing studies aiming at the constant monitoring of juvenile levels captured.

Distribution of the transcription factor islet-1 in the central nervous system of nonteleost actinopterygian fish: Relationship with cholinergic and catecholaminergic systems.

Islet-1 (Isl1) is one of the most conserved transcription factors in the evolution of vertebrates, due to its continuing involvement in such important functions as the differentiation of motoneurons, among other essential roles in cell fate in the forebrain. Although its functions are thought to be similar in all vertebrates, the knowledge about the conservation of its expression pattern in the central nervous system goes as far as teleosts, leaving the basal groups of actinopterygian fishes overlooked, despite their important phylogenetic position. In order to assess the extent of its conservation among vertebrates, we studied its expression pattern in the central nervous system of selected nonteleost actinopterygian fishes. By means of immunohistochemical techniques, we analyzed the Isl1 expression in the brain, spinal cord, and sensory ganglia of the cranial nerves of young adult specimens of the cladistian species Polypterus senegalus and Erpetoichthys calabaricus, the chondrostean Acipenser ruthenus, and the holostean Lepisosteus oculatus. We also detected the presence of the transcription factor Orthopedia and the enzymes tyrosine hydroxylase (TH) and choline acetyltransferase (ChAT) to better locate all the immunoreactive structures in the different brain areas and to reveal the possible coexpression with Isl1. Numerous conserved features in the expression pattern of Isl1 were observed in these groups of fishes, such as populations of cells in the subpallial nuclei, preoptic area, subparaventricular and tuberal hypothalamic regions, prethalamus, epiphysis, cranial motor nuclei and sensory ganglia of the cranial nerves, and the ventral horn of the spinal cord. Double labeling of TH and Isl1 was observed in cells of the preoptic area, the subparaventricular and tuberal hypothalamic regions, and the prethalamus, while virtually all motoneurons in the hindbrain and the spinal cord coexpressed ChAT and Isl1. Altogether, these results show the high degree of conservation of the expression pattern of the transcription factor Isl1, not only among fish, but in the subsequent evolution of vertebrates.

NeuRegenerate: A Framework for Visualizing Neurodegeneration.

Recent advances in high-resolution microscopy have allowed scientists to better understand the underlying brain connectivity. However, due to the limitation that biological specimens can only be imaged at a single timepoint, studying changes to neural projections over time is limited to observations gathered using population analysis. In this article, we introduce NeuRegenerate, a novel end-to-end framework for the prediction and visualization of changes in neural fiber morphology within a subject across specified age-timepoints. To predict projections, we present neuReGANerator, a deep-learning network based on cycle-consistent generative adversarial network (GAN) that translates features of neuronal structures across age-timepoints for large brain microscopy volumes. We improve the reconstruction quality of the predicted neuronal structures by implementing a density multiplier and a new loss function, called the hallucination loss. Moreover, to alleviate artifacts that occur due to tiling of large input volumes, we introduce a spatial-consistency module in the training pipeline of neuReGANerator. Finally, to visualize the change in projections, predicted using neuReGANerator, NeuRegenerate offers two modes: (i) neuroCompare to simultaneously visualize the difference in the structures of the neuronal projections, from two age domains (using structural view and bounded view), and (ii) neuroMorph, a vesselness-based morphing technique to interactively visualize the transformation of the structures from one age-timepoint to the other. Our framework is designed specifically for volumes acquired using wide-field microscopy. We demonstrate our framework by visualizing the structural changes within the cholinergic system of the mouse brain between a young and old specimen.

Shape variation in the limb long bones of modern elephants reveals adaptations to body mass and habitat.

During evolution, several vertebrate lineages have shown trends towards an increase in mass. Such a trend is associated with physiological and musculoskeletal changes necessary to carry and move an increasingly heavy body. Due to their prominent role in the support and movement of the body, limb long bones are highly affected by these shifts in body mass. Elephants are the heaviest living terrestrial mammals, displaying unique features allowing them to withstand their massive weight, such as the columnarity of their limbs, and as such are crucial to understand the evolution towards high body mass in land mammals. In this study, we investigate the shape variation of the six limb long bones among the modern elephants, Elephas maximus and Loxodonta africana, to understand the effect of body mass and habitat on the external anatomy of the bones. To do so, we use three-dimensional geometric morphometrics (GMMs) and qualitative comparisons to describe the shape variation, at both the intraspecific and interspecific levels. Our results reveal that the two species share similar negative ontogenetic allometric patterns (i.e. becoming stouter with increased length) in their humerus and femur, but not in the other bones: the proximal epiphyses of the stylopod bones develop considerably during growth, while the distal epiphyses, which are involved in load distribution in the elbow and knee joints, are already massive in juveniles. We attribute this pattern to a weight-bearing adaptation already present in young specimens. Among adults of the same species, bone robustness increases with body mass, so that heavier specimens display stouter bones allowing for a better mechanical load distribution. While this robustness variation is significant for the humerus only, all the other bones appear to follow the same pattern. This is particularly visible in the ulna and tibia, but less so in the femur, which suggests that the forelimb and hindlimb adapted differently to high body mass support. Robustness analyses, while significant for the humerus only, suggest more robust long bones in Asian elephants than in African savanna elephants. More specifically, GMMs and qualitative comparisons indicate that three bones are clearly distinct when comparing the two species: in E. maximus the humerus, the ulna and the tibia display enlarged areas of muscular insertions for muscles involved in joint and limb stabilization, as well as in limb rotation. These results suggest a higher limb compliance in Asian elephants, associated with a higher dexterity, which could be linked to their habitat and foraging habits.

Chromatic polymorphism in Trichomycterus albinotatus (Siluriformes, Trichomycteridae), a mountain catfish from south-eastern Brazil and the role of colouration characters in trichomycterine taxonomy

Colouration is an important tool for systematists inferring species limits and phylogenetic relationships of teleost fishes, but the use of colouration variation in trichomycterine catfish systematics has generated some controversy. We first report and describe the occurrence of four, geographically disjunct colour morphs inTrichomycterus albinotatus, endemic to south-eastern Brazil, as well as ontogenetic colouration change in each morph. A phylogenetic analysis using a cytb fragment (1098 bp) for 23 specimens representing all colour morphs and four outgroups did not support any correlation between colour morphs and lineages, with different colour morphs sharing identical haplotypes. This study indicated that young adult specimens found in lighter habitats had white and brown to black spots on the flank, whereas similar-sized specimens inhabiting darker habitats had white spots inconspicuous or absent and dark brown or black spots expanded. Individuals above about 65 mm SL of all populations had flank white marks less conspicuous or absent and cryptic habits during daylight, contrasting with smaller individuals with white marks and actively swimming above the substrate. Literature data indicate that ontogenetic colouration and habit changes occur in different trichomycterid lineages. Our data thus show that colouration may be problematic in taxonomical studies, although often being consistently used to diagnose species and clades. We conclude that colouration should not be discarded a priori as evidence of trichomycterine relationships and species limits, but should be used with caution in systematic studies, being necessary additional evidence, such as osteological characters or molecular data.

Revealing the Permanent and Transient Plant Understory in Gallery Forests in the Cerrado of Central Brazil

Abstract The understories of tropical forests comprise complex communities and can be divided into permanent understory, where the generally shade-tolerant plant growth forms are less developed in height, and transient understory, where young tree individuals are only temporarily present. Despite a high contribution to species richness in tropical forests, the understory is poorly studied. Here, we examined the species composition, richness, structure, diversity, and the relative contribution of growth forms in permanent and transient understories of gallery forests in the Brazilian Cerrado. A total of 211 species distributed into sixty-seven families and 153 genera were sampled. The most species-rich family was Rubiaceae, and Miconia was the genus with the highest species richness. The species Hildaea pallens had the highest importance in the forests. The best-represented growth forms were tree seedlings, followed by shrubs and lianas. The transient component of the understory in gallery forests was the most diverse. However, in terms of species relative cover, both transient and permanent understory species contributed equally to the understory structure, mainly due to the high cover of Poaceae species. Our study is the first to examine composition, structure, diversity, and growth forms in the permanent and transient understories of gallery forests. Study Implications: Our study is innovative in describing the plant community attributes of gallery forest understories in the Brazilian Cerrado. The understories of tropical forests comprise complex communities and can be divided into permanent and transient understory. The transient component of the understory in gallery forests was the most diverse, represented by seedlings and young tree specimens. However, in terms of species relative cover, both transient and permanent understory species contributed equally to the understory structure. Here, we provide evidence that may be useful to initiatives seeking to conduct ecological restoration and conservation of gallery forests in the Cerrado.