Morunasaurus is a genus of Neotropical iguanid lizards of the family Hoplocercidae, inhabiting Central and northwestern South America. Their phylogenetic relationships are not completely clear but ...being presumably paraphyletic. Its type species, M. groi, is very rare, known only from two single localities and a handful of specimens. Here I report a new occurrence of this species for Colombia, which constitutes the southeastern record to the date, extending the species range by about 175 km and 510 m altitudinally. Additionally, I discuss about the intraspecific differences in coloration between Panamanian and Colombian specimens.
We assessed the current knowledge on non-avian reptile species composition in the state of Rio de Janeiro (RJ), southeastern Brazil. We used published data in indexed journals and verified voucher ...specimens housed in two herpetological collections of the Museu Nacional (UFRJ), and the Laboratory of Reptiles (ZUFRJ). We also confirmed vouchers from Instituto Vital Brazil (IVB) and from the Museum of Comparative Zoology (MCZ). We compiled a list containing 149 species of reptiles, distributed among Testudines (N = 15), Crocodylia (N = 1) and Squamata (N = 133; six amphisbaenians, 38 lizards and 89 snakes). Our results add 20 species to the previous list known for the state. Four species recorded are endemic to the state of Rio de Janeiro (Anolis neglectus, Glaucomastix littoralis, Leposternon scutigerum, and Liolaemus lutzae). We identified that 21 reptile species recorded in RJ state (nearly 15% of the total) are included in some threat category either in the IUCN, Brazilian (ICMBio) or state lists of endangered species. We also report that seven of the reptiles recorded are non-indigenous to the state: Cnemidophorus aff. lemniscatus (= Cnemidophorus cryptus), Anolis sagrei, Trachemys scripta, Trachemys dorbigni, Hemidactylus mabouia, Crotalus durissus terrificus, and Rhinoclemmys punctularia. The checklist presented here provides a comprehensive database for further research on the herpetofauna of the Brazilian Atlantic Forest.
Here, we report the efficient loading of Juniperus squamata root essential oil (JSEO) on polyvinylpyrrolidone (PVP) functionalized graphene oxide (GO-PVP) and investigated cytotoxic potential of ...GO-PVP-JSEO against human breast cancer cells MDA-MD-231. For this, modified Hummer's method was used to synthesize GO followed by its functionalization with PVP. Loading of JSEO on nanocarriers i.e., GO and GO-PVP was carried out through the π-π/hydrophobic interactions and we found that GO-PVP (17.4%) exhibit higher JSEO loading capacity in comparison to GO (13.6%). Further, GC and GC–MS techniques were used to analyze biologically active phytochemicals, which enabled the identification of sixty-four (64) compounds. To characterize the synthesize nanocomposites, latest spectroscopic techniques viz. Raman, FT-IR, XRD, SEM were used. Moreover, the cell survival percentages of GO-PVP-JSEO treated MDA-MD-231 human breast cancer cells at 20 μg/mL concentration were about 68%, 32.74%, and 21%, after 24 h, 48 h and 72 h, respectively. These results reveal the enhanced anticancer activity of GO-PVP-JSEO nanocarrier in comparison to JSEO alone. Overall, our novel finding shows that JSEO loaded GO-PVP nanocarrier could be a promising platform for breast cancer therapy. Also, future pre-clinical and clinical studies are urgently needed to evaluate the safety and efficacy of GO-PVP-JSEO for treating breast cancer.
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•Extraction of essential oil from Juniperus squamata (JS) root and its characterization using GC and GC–MS techniques.•An efficient loading of JS root essential oil (JSEO) on polyvinylpyrrolidone (PVP) functionalized GO (GO-PVP).•Evaluation of GO-PVP-JSEO composite's cytotoxicity against human breast cancer MDA MB 231 cells.•Essential oil loaded GO-PVP exhibited higher cytotoxic effects than pure essential oil to the human breast cancer cells.
Abstract
Despite increased use of genomic data in phylogenetics, morphological information remains vital for resolving evolutionary relationships, particularly for fossil taxa. The properties and ...models of evolution of molecular sequence data are well characterized and mature, relative to those of morphological data. Furthermore, heterogeneity, integration and relative homoplasy of empirical morphological data could prove problematic for phylogenetic reconstruction. Here we compare osteological and non-osteological characters of 28 morphological datasets of extant saurians in terms of their homoplasy relative to molecular trees. Analysis of individual avian datasets finds osteological characters to be significantly more consistent with molecular data than soft characters are. Significant differences between morphological partitions were also observed in the age at which characters resolved on molecular trees. Osteological character changes occur relatively earlier in deep branches, whilst soft-tissue character transitions are more recent in shallow branches. The combined results demonstrate differences in evolutionary dynamics between morphological partitions. This may reflect evolutionary constraints acting on osteological characters, compared with the relative lability of soft characters. Furthermore, it provides some support to phylogenetic interpretations of fossil data, including dinosaurs, which are predominately osteological. Recent advances in amphibian and mammal phylogenetics may make these patterns possible to test for all tetrapods.
Tantilla boipiranga is a rare vulnerable snake found in the Atlantic Forest, distributed in the phytophysiognomy of rocky grasslands (campos rupestres), in southeastern Brazil. Here, we update the ...known geographic range of the species to eight new localities in the state of Minas Gerais, Brazil, extending its distribution approximately 400 km northwards to the municipality of Almenara, from the previous northernmost record, and 703 km from the type locality.
AIM: Size is one of the most important and obvious traits of an organism. Both small and large sizes have adaptive advantages and disadvantages. Body size–frequency distributions of most large clades ...are unimodal and right skewed. Species larger than the mean or range midpoint of body sizes are relatively scarce. Theoretical models suggest evolutionary rates are higher in small organisms with short generation times. Therefore diversification rates are usually thought to be maximal at relatively small body sizes. Empirical studies of the rates of molecular evolution and clade diversification, however, have usually indicated that both are unrelated to body size. Furthermore, it has been claimed that because snakes are longer than lizards, the size–frequency distribution of all squamate species is bimodal overall. We examined the shape of the size–frequency distribution of nearly all Squamata and Rhynchocephalia species, and investigated how size affected diversification rates. LOCATION: Global. METHODS: We collected data on maximum body length for 9805 lepidosaur (squamates and the tuatara) species (99.7% of all species) and converted them to mass using clade‐specific allometric equations. Using methods that test for relationships between continuous traits and speciation and extinction rates on a large, dated phylogeny (4155 species), we investigated the relationship between diversification rates and body size. RESULTS: Living squamates span six orders of magnitude in body size, eight when giant extinct snakes and mosasaurs are included. The body size–frequency distributions of snakes and lizards separately, and of all lepidosaur species combined, are unimodal and right skewed. Nonetheless, we find neither linear nor hump‐shaped relationships between size and diversification rates, except in snakes, where speciation and diversification are hump shaped. MAIN CONCLUSIONS : Despite a clear modality and skew in the body sizes of lepidosaurs, we find little evidence for faster diversification of modal‐sized taxa, perhaps implying that larger‐sized clades are relatively young.
Aim
The aim was to determine how reptile populations respond to anthropogenic habitat modification and determine whether species traits and environmental factors influence such responses.
Location
...Global.
Time period
1981–2018.
Major taxa studied
Squamata.
Methods
We compiled a database of 56 studies reporting how habitat modification affects reptile abundance and calculated standardized mean differences in abundance (Hedges’ g). We used Bayesian meta‐analytical models to test whether responses to habitat modification depended on body size, clutch size, reproductive mode, habitat specialization, range size, disturbance type, vegetation type, temperature and precipitation.
Results
Based on 815 effect sizes from 376 species, we found an overall negative effect of habitat modification on reptile abundance (mean Hedges’ g = −0.43, 95% credible intervals = −0.61 to −0.26). Reptile abundance was, on average, one‐third lower in modified compared with unmodified habitats. Small range sizes and small clutch sizes were associated with more negative responses to habitat modification, although the responses were weak and the credible intervals overlapped zero. We detected no effects of body size, habitat specialization, reproductive mode (egg‐laying or live‐bearing), temperature or precipitation. Some families exhibited more negative responses than others, although overall there was no phylogenetic signal in the data. Mining had the most negative impacts on reptile abundance, followed by agriculture, grazing, plantations and patch size reduction, whereas the mean effect of logging was neutral.
Main conclusions
Habitat modification is a key cause of reptile population declines, although there is variability in responses both within and between species, families and vegetation types. The effect of disturbance type appeared to be related to the intensity of habitat modification. Ongoing development of environmentally sustainable practices that ameliorate anthropogenic impacts is urgently needed to prevent declines in reptile populations.
Viviparity has putatively evolved 115 times in squamates (lizards and snakes), out of only ~ 140 origins in vertebrates, and is apparently related to colder climates and other factors such as body ...size. Viviparity apparently evolves from oviparity via egg‐retention, and such taxa may thus still have the machinery to produce thick‐shelled eggs. Parity mode is also associated with variable diversification rates in some groups. We reconstruct ancestral parity modes accounting for state‐dependent diversification in a large‐scale phylogenetic analysis, and find strong support for an early origin of viviparity at the base of Squamata, and a complex pattern of subsequent transitions. Viviparous lineages have higher rates of speciation and extinction, and greater species turnover through time. Viviparity is associated with lower environmental and body temperatures in lizards and amphisbaenians, but not female mass. These results suggest that parity mode is a labile trait that shifts frequently in response to ecological conditions.
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