Phylogeny and conservation status of the Indian egg-eater snake, Elachistodon westermanni Reinhardt, 1863 (Serpentes, Colubridae)

2018 ◽  
Vol 39 (3) ◽  
pp. 317-324 ◽  
Author(s):  
Ashwini Venkatanarayana Mohan ◽  
Avinash C. Visvanathan ◽  
Karthikeyan Vasudevan

Abstract The Indian egg-eater (Elachistodon westermanni) is a monotypic species of the Genus Elachistodon distributed across the Indian sub-continent. In Africa, there are 13 species of egg-eating snakes of the Genus Dasypeltis. These two genera, Elachistodon and Dasypeltis were thought to be closely related due to similar diet specialization, and shared biogeographic history between the Indian sub-continent and the continent of Africa. In our study, we amplified three mitochondrial genes and one nuclear gene from E. westermanni and reconstructed molecular phylogeny utilizing published sequences to understand the evolutionary relationships between the African, and the Indian egg-eating snakes. We used morphological characters to reinforce our inferences on phylogenetic relationships. We show that the Indian egg-eater is sister to cat snakes of the Genus Boiga, and it does not share recent ancestry with the African egg-eating snakes. Morphological character states point at similarities between Elachistodon and Dasypeltis only in characters associated with their feeding behaviour. Elachistodon westermanni was similar to the Boiga spp. in several other morphological characters, and we provisionally assign E. westermanni under the genus Boiga. Compilation of records of E. westermanni across the Indian sub-continent over the years revealed a positive “Lazarus” effect. We conclude that, the egg-eating behaviour and the associated morphological characters in the snake genera Dasypeltis and Elachistodon are a result of convergent evolution. Based on the conservation status of E. westermanni, it could serve as a flagship species to conserve important wildlife habitats that are being lost rapidly in India.

2009 ◽  
Vol 21 (6) ◽  
pp. 565-570 ◽  
Author(s):  
Kristen L. Kuhn ◽  
Thomas J. Near

AbstractThe biota of Antarctica is amazingly rich and highly endemic. The phylogenetics of notothenioid fishes has been extensively investigated through analyses of morphological characters, DNA sequences from mitochondrial genes, and single copy nuclear genes. These phylogenetic analyses have produced reasonably similar phylogenetic trees of notothenioids, however a number of phylogenetic questions remain. The nototheniid clade Trematomus is an example of a group where phylogenetic relationships remain unresolved. In this paper we revisit the phylogenetic relationships of Trematomus using both increased taxon sampling and an expanded dataset which includes DNA sequences from two mitochondrial genes (ND2 and 16S rRNA) and one single-copy nuclear gene (RPS7). The Bayesian phylogeny resulting from the analysis of the combined mitochondrial and nuclear gene datasets was well resolved and contained more interspecific nodes supported with significant Bayesian posteriors than either the mitochondrial or nuclear gene phylogenies alone. This demonstrates that the addition of nuclear gene sequence data to mitochondrial data can enhance phylogenetic resolution and increase node support. Additionally, the results of the combined mitochondrial and nuclear Bayesian analyses provide further support for the inclusion of species previously classified as Pagothenia and Cryothenia in Trematomus.


2008 ◽  
Vol 39 (4) ◽  
pp. 431-460 ◽  
Author(s):  
Jakob Damgaard

AbstractThe phylogeny of semi-aquatic bugs (Hemiptera-Heteroptera: Gerromorpha) was tested in parsimony analyses of 64 morphological characters and approximately 2.5 kb of DNA sequence data from the mitochondrial genes encoding COI+II and 16SrRNA and the nuclear gene encoding 28SrRNA. The taxon sample included representatives of all families and most subfamilies of Gerromorpha and a selection of outgroup taxa representing the two basal infraorders of Heteroptera, Enicocephalomorpha and Dipsocoromorpha, and two families of Nepomorpha. A simultaneous analysis (SA) of all data, and with gaps scored as fifth state characters, gave a single most parsimonious tree with all families resolved as monophyletic, except the Veliidae, where Microveliinae + Haloveliinae, Veliinae, Rhagoveliinae, Perittopinae, and Ocelloveliinae were resolved as successive sister groups to the Gerridae, thus confirming earlier statements about paraphyly of this family. The Gerridae + Veliidae clade was strongly supported, but otherwise only the Gerridae + Veliidae less Ocelloveliinae and the Gerridae itself had support. These three clades could all be diagnosed on apomorphic morphological characters, although no characters diagnosing the Gerridae were without convergences or present in all included taxa. While the Ocelloveliinae, Veliinae and Haloveliinae could not be diagnosed on convincing apomorphies, the Microveliinae + Haloveliinae, and their sister group relationship with the Gerridae, could be diagnosed on rather strong morphological synapomorphies, suggesting that Gerridae could be expanded to include these two veliid subfamilies, while Ocelloveliinae, and perhaps the remaining veliid subfamilies, could be elevated to new families. In Gerridae, the Ptilomerinae + Halobatinae was sister group to all other subfamilies, while the Rhagadotarsinae + Trepobatinae was sister group to a clade comprising the Gerrinae, Eotrechinae, Cylindrostethinae and Charmatometrinae. Most relationships in this clade were poorly supported and diagnosed, and Cylindrostethinae was surprisingly found to be paraphyletic. The sister group to the Gerridae + Veliidae clade was a strongly supported clade comprising the Paraphrynoveliidae and Macroveliidae, and this, and the lack of convincing synapomorphies for Paraphrynoveliidae, suggest that these two small families could be synonymized. For the basal relationships of Gerromorpha, the Mesoveliidae was strongly supported sister group to all other families, while the Hebridae, Hermatobatidae and Hydrometridae formed a poorly supported and poorly diagnosed sister group to the Gerridae + Veliidae + Paraphrynoveliidae + Macroveliidae clade. The unexpected sister group relationship between Hermatobatidae and Hydrometridae was moderately supported, and could be diagnosed on two synapomorphies, thus giving a new hypothesis about the relationships of these very divergent families. Phylogenetic analyses of individual character partitions gave less resolved and less supported relationships, and the mitochondrial genes COI+II and 16SrRNA contributed negative hidden partitioned Bremer support (HPBS) to the simultaneous analysis tree, probably due to homoplasy caused by saturation effects.


2010 ◽  
Vol 101 (1) ◽  
pp. 115-123 ◽  
Author(s):  
W. Lee ◽  
H. Kim ◽  
S. Lee

AbstractWe performed molecular and morphological analyses to determine the generic limit of the genus Aulacorthum, including several species with controversial taxonomic histories. The sequences of four mitochondrial genes, COI, COII, srRNA and lrRNA, and one nuclear gene, EF1a, implied that Aulacorthum is not monophyletic, with Aulacorthum magnoliae and Aulacorthum nipponicum forming a clade that is not sister to other currently recognized Aulacorthum species. Morphometric analysis based on 20 morphological characters also showed that A. magnoliae and A. nipponicum exhibited morphological characteristics distinct from congeneric species. Based on these results, we propose a new genus, Neoaulacorthum ge. n., for A. magnoliae and A. nipponicum.


2019 ◽  
Vol 27 (4) ◽  
pp. 238-247
Author(s):  
Massoud Ranjbar ◽  
Narges Rahchamani

Scrophularia dianatnejadii Ranjbar & Rahchamani, a new species from Tehran Province in northern Iran, is described and illustrated. It is closely related to S. amplexicaulis Benth. and shares with it some diagnostic morphological characters such as habit, plant indument, phyllotaxy, and corolla shape and color. Both species are placed in Scrophularia L. sect. Mimulopsis Boiss. Macro- and micromorphological characters of the two are examined and compared. Pollen morphology of these species is investigated using SEM. Detailed descriptions, illustrations, distribution maps, and conservation status of both species are provided.


Genetics ◽  
2001 ◽  
Vol 157 (4) ◽  
pp. 1711-1721
Author(s):  
Donald L Auger ◽  
Kathleen J Newton ◽  
James A Birchler

Abstract Each mitochondrion possesses a genome that encodes some of its own components. The nucleus encodes most of the mitochondrial proteins, including the polymerases and factors that regulate the expression of mitochondrial genes. Little is known about the number or location of these nuclear factors. B-A translocations were used to create dosage series for 14 different chromosome arms in maize plants with normal cytoplasm. The presence of one or more regulatory factors on a chromosome arm was indicated when variation of its dosage resulted in the alteration in the amount of a mitochondrial transcript. We used quantitative Northern analysis to assay the transcript levels of three mitochondrially encoded components of the cytochrome c oxidase complex (cox1, cox2, and cox3). Data for a nuclearly encoded component (cox5b) and for two mitochondrial genes that are unrelated to cytochrome c oxidase, ATP synthase α-subunit and 18S rRNA, were also determined. Two tissues, embryo and endosperm, were compared and most effects were found to be tissue specific. Significantly, the array of dosage effects upon mitochondrial genes was similar to what had been previously found for nuclear genes. These results support the concept that although mitochondrial genes are prokaryotic in origin, their regulation has been extensively integrated into the eukaryotic cell.


1992 ◽  
Vol 11 (2) ◽  
pp. 197-209 ◽  
Author(s):  
Andrew Racey

Abstract. The main evolutionary trends in the nummulites are briefly summarised and the value of certain morphological characters in species discrimination are summarised. The degree of interdependence of each morphological character on all other characters is assessed and the characters are weighted in order of importance. Environmental and ontogenetic effects on each character are then reviewed and the characters reweighted in order of importance.


2021 ◽  
Vol 50 (2) ◽  
pp. 319-326
Author(s):  
Süleyman Doğu ◽  
Yavuz Bağci

Stachys ahmet-savranii Doğu & Bağcı sp. nov. (Lamiaceae) from the Niğde (C5 Niğde, Turkey) is described and illustrated. It exhibits general features of the section Infrarosularis. It is closely related to Stachys citrina Boiss. & Heldr. but differs by its slender and unbranched stem; leaves structure; floral leaves equalling or longer than verticillasters; verticillester with 8 - 12 flowered and corolla 10 - 18 mm; Bracteoles reaching nearly middle of calyx tube. Diagnostic morphological characters are discussed. The geographical distribution of the new species is mapped. Notes are also presented on its ecology, biogeography and conservation status. Bangladesh J. Bot. 50(2): 319-326, 2021 (June)


2007 ◽  
Vol 85 (9) ◽  
pp. 985-993 ◽  
Author(s):  
E.E. Fraser ◽  
M.B. Fenton

Eating behaviour can vary with age, experience, and gender, as well as food hardness. This variation can contribute to intraspecific dietary differences and may result in variable definitions of optimal foraging and decreased intraspecific competition. We quantified feeding behaviour of insectivorous bats eating hard and soft mealworm-based food items based on the bats’ ability to consume and manipulate food items, consumption time, chew frequency, and total chews to consume. Adult Myotis lucifugus (LeConte, 1831) were more successful at both consuming and manipulating mealworms and consumed mealworms more quickly, with greater chew frequency and in fewer chews, than did subadults. Adults chewed mealworm viscera more frequently than did subadults but showed no differences in the other variables. Adult Eptesicus fuscus (Beauvois, 1796) consumed mealworms more quickly and with fewer chews than did subadults but showed no differences in the other variables. There were no differences between adult and subadult E. fuscus when consuming mealworm viscera. Male and female M. lucifugus did not differ significantly when eating either mealworms or mealworm viscera. There was no change in subadult consumption time of mealworms over the summer. Age-based differences in eating abilities may play a role in defining optimal foraging and dietary composition in insectivorous bats.


2018 ◽  
Vol 24 (1) ◽  
pp. 1
Author(s):  
Janne H.W. Rembang ◽  
Abdul W. Rauf ◽  
Joula O.M. Sondakh

<p>Local rice is a potential germplasm as a source of genes that control important properties in rice plants. The research aimed to characterize the morphological character of local rice cultivars of North Sulawesi. The research was conducted from January to June 2015 in North Sulawesi. The method used was the descriptive qualitative method. Exploration was done by collecting samples of local rice cultivars in North Sulawesi. Each cultivar was characterized its morphological characters according to the Characterization and Evaluation Guidelines of Rice Germplasm. The local rice found in North Sulawesi were 10 varieties, namely Pulo Sawah, Superwin, CK, Serwo, Pilihan, Sako, Sito Merah, Sito Putih, TB, and Serayu. There were similarities of the characters from all local rice varieties of North Sulawesi, such as culm (culm strength and culm habit), leaf character (basal leaf sheath color, leaf blade color, collar color, and auricle color), and flower character (panicle exsertion and panicle attitude of branches). The character of grain morphology was very diverse for all local rice varieties of North Sulawesi.</p>


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