Assessing extinction risk from geographic distribution data in Neotropical freshwater fishes

The IUCN Red List (RL) provides high-quality conservation assessments for individual species, yet the rate and scale of environmental deterioration globally challenges the conservation community to develop expedited methods for risk assessment. Here we compare threat assessments for 3,001 species of Neotropical freshwater fishes (NFF) in the IUCN-RL using readily accessible data types as proxies for extinction risk: geographic range, elevation, and species publication date. Furthermore, using geographic and taxonomic data alone, we generated preliminary conservation assessments for 2,334 NFF species currently awaiting IUCN assessment, identifying an additional 671 NFF species as potentially threatened. This number of potentially threatened species represents an increase of 59% over the number of species currently assigned to threat categories by the IUCN-RL. These results substantially expand the number of threatened NFF species from 422 currently on the IUCN RL to 1,093 species as threatened or potentially threatened, representing about 18% of all NFF species. Extinction risk is greater in species with smaller geographic ranges, which inhabit upland rivers, and which were described more recently. We propose the Central and Southern Andes, and Eastern Guiana Shield as priorities in the upcoming IUCN RL assessment of NFF species conservation risk.(AU)

A Lista Vermelha (IUCN) fornece avaliações precisas sobre status de conservação das espécies, porém a taxa e escala de deterioração ambiental desafia a comunidade conservacionista a desenvolver métodos rápidos para avaliações de riscos de extinção. Aqui, comparamos as avaliações da IUCN para 3.001 espécies de peixes dulcícolas neotropicais com dados facilmente acessíveis de risco de extinção: extensão de ocorrências, altitude e data de publicação das espécies. Além disso, usando apenas dados geográficos e taxonômicos, geramos avaliações preliminares de conservação para 2.334 espécies de peixes neotropicais aguardando avaliação da IUCN, e identificamos 671 espécies adicionais como potencialmente ameaçadas. Este número de espécies potencialmente ameaçadas representa um aumento de 59% em relação aquelas classificadas nas categorias de ameaça pela IUCN. Estes resultados expandem o número de espécies ameaçadas segundo a IUCN de 422 para 1.093 espécies ameaçadas ou potencialmente ameaçadas, representando cerca de 18% das espécies de peixes neotropicais. O risco de extinção é maior para espécies com distribuições geográficas restritas, que habitam rios de terras altas e que foram descritas mais recentemente. Sugerimos a região Central e Meridional do Andes e o Escudo das Guianas Orientais como prioridades para as próximas avaliações da IUCN sobre a conservação das espécies de peixes dulcícolas neotropicais.(AU)

Morphological and Morphometrical Studies on the Skull of Binturong (Arctictis binturong)

The binturong or bearcat is the largest species of the family Viverridae. It is uncommon in much of its range and has been assessed as vulnerable on the IUCN red list. The size of the head was small, narrow and light in proportion to the body. The skull of the binturong was dolichocephalic as per the cephalic index (56.25). There was no prominent internasal suture and the orbits were incomplete with optic foramen present near the ventral surface. The mean skull length, skull width, skull base length, cranial length, cranial width, cranial height, were 14.95±0.10 cm, 8.47±0.10 cm, 15.07±0.02 cm, 11.16±0.09 cm, 6.56±0.11 cm, 3.16±0.08 cm, respectively. The mean facial length, facial width, maxilla length, maxilla height, distance between infraorbital foramen, diameter of infraorbital foramina, nasal length, nasal width were 4.95±0.08 cm, 6.14±0.12 cm, 4.46±0.01 cm, 3.83±0.02 cm, 4.68±0.10 cm, 0.49±0.07 cm, 2.94±0.03 cm, 1.97±0.11 cm, respectively. Scanty literature available on morphological and morphometrical studies of the skull of binturong. Therefore this present study was aimed to establish a morphometric database that will eventually guide the use of these measurements for diagnosis and treating different disorders

Evolutionary analysis of genus Channa based on karyological and 16S rRNA sequence data

A wide range of diploid number of chromosomes and the body size of Channa congeners are useful combination of characters for studying the factors controlling the body size. In this study, the karyological information was superimposed on the evolutionary tree generated by 16S rRNA mitochondrial gene sequences. Here, the metaphase chromosome complements stained with Giemsa, AgNO3 and CMA3 were prepared from six snakehead murrel fish species collected from northeast India. The diploid chromosome numbers and the fundamental arms of C. aurantimaculata (2n = 52, NF = 98), C. gachua (2n = 56, NF = 84), C. marulius (2n = 44, NF = 58), C. orientalis (2n = 52, NF = 74), C. punctata (2n = 32, NF = 60) and C. striata (2n = 40, NF = 48) were calculated by the analysis of metaphase chromosome complements. Both methods of nucleolar organizer region (NOR) localization, silver nitrate and chromomycin A3, revealed NOR pairs of 1, 2, 3, 1, 4 and 3 in C. aurantimaculata, C. gachua, C. marulius, C. orientalis, C. punctata and C. striata, respectively. The subject species showed primitive type of asymmetrical chromosomes, except the C. punctata. The variation in 2n for C. orientalis (2n = 52, 78) and C. gachua (2n = 52, 78, 104) of a complete haploid set indicates the possibility of either ploidy change in . orientalisC and C. gachua, if we consider 2n = 52 or the Robertsonian rearrangements in different populations of these two species. The chromosome evolution tree was constructed on 16S rRNA ML-phylogenetic tree using ChromEvol 1.3. The analysis of chromosome evolution explained the loss or gain of chromosome, duplications or semiduplications mechanism. For time scaling the chromosomeevolution, the node age of available 16S rRNA gene of Channa species were estimated, which was also used for estimating the time when chromosomal changes occurred in context of geological time-scale.

Spondias tuberosa Arruda (Anacardiaceae), a threatened tree of the Brazilian Caatinga? / Spondias tuberosa Arruda (Anacardiaceae), uma árvore ameaçada de extinção da Caatinga?

Abstract Spondias tuberosa Arr., a fructiferous tree endemic to the northeast Brazilian tropical dry forest called Caatinga, accounts for numerous benefits for its ecosystem as well as for the dwellers of the Caatinga. The tree serves as feed for pollinators and dispersers as well as fodder for domestic ruminants, and is a source of additional income for local smallholders and their families. Despite its vantages, it is facing several man-made and natural threats, and it is suspected that S. tuberosa could become extinct. Literature review suggests that S. tuberosa suffers a reduced regeneration leading to population decrease. At this juncture S. tuberosa cannot be considered threatened according to the International Union for Conservation of Nature Red List Categories and Criteria, as it has not yet been assessed and hampered generative regeneration is not considered in the IUCN assessment. The combination of threats, however, may have already caused an extinction debt for S. tuberosa. Due to the observed decline in tree density, a thorough assessment of the S. tuberosa population is recommended, as well as a threat assessment throughout the entire Caatinga.

Resumo Spondias tuberosa Arr., é uma árvore frutífera endêmica da Caatinga, floresta seca tropical localizada no Nordeste do Brasil. A árvore traz diversos benefícios para o ecossistema e para a população local. Ela serve de alimento tanto para polinizadores e dispersores quanto para ruminantes domésticos e é fonte de renda extra para os agricultores familiares da região. Apesar de seus benefícios, esta árvore enfrenta várias ameaças naturais e antrópicas que podem levar a sua extinção. A revisão da literatura científica sugere que S. tuberosa sofre de reduzida capacidade de regeneração, o que leva à diminuição da população. Todavia, S. tuberosa não é considerada uma espécie ameaçada de extinção de acordo com as categorias e critérios da Lista Vermelha da União Internacional para a Conservação da Natureza, já que a espécie ainda não foi avaliada e capacidade regenerativa reduzida não é considerado critério pelo UICN. A combinação de ameaças, entretanto, pode já ter levado ao débito de extinção da S. tuberosa. Devido ao declínio observado da densidade das árvores, recomenda-se uma avaliação completa da população de S. tuberosa e uma avaliação de todas as ameaças sofridas pela árvore na Caatinga.