Molecular phylogenetics and medicinal plants of Asclepiadoideae from India

published_or_final_versionabstractBiological SciencesDoctoralDoctor of Philosoph

Spiranthes himalayensis (Orchidaceae, Orchidoideae) a new species from Asia

Spiranthes himalayensis is described here as a new species based primarily on molecular phylogenetic evidence followed by morphological comparison with other Asian Spiranthes species. It is distributed widely from southern India to tropical China. Phylogenetic analysis shows its close affinity to S. nivea which is endemic to Taiwan. Morphologically, the new species looks close to S. sinensis and S. hongkongensis. S. himalayensis is an allogamous species which can be differentiated from its allies on the basis of pubescent plant body, floral bract longer or of the same length as that of ovary, petals with blunt apex, labellum width around hypochile same as the width of epichile, epichile widely flabellate or semi-tunicate, column length equal to or more than 1.5mm, clavate operculum attached to the column on the broader part by an arm-like extension emerging from the upper part of column and a well developed rostellum partitioning the stigma and pollinarium

Generic identity of Camptorrhiza indica (Colchicaceae) based on cytogenetics and molecular phylogenetics

The tribe Iphigenieae (Colchicaceace, Liliales) includes two genera, viz. Camptorrhiza and Iphigenia, which are distributed in Africa, India, and Australasia. Iphigenia is represented by 12 species, of which six occur in India while Camptorrhiza comprises one species each in Africa (C. strumosa) and India (C. indica). The genus Camptorrhiza possesses a knee-shaped tuber attached to the corms, filaments with a thick bulge in the middle and styles with single stigma. Iphigenia on the other hand lacks knee-shaped tuber, bears linear filaments and has styles with three stigmas. Camptorrhiza indica possesses ovoid corms, linear filaments and styles with a single stigma. These characters are intermediate between Iphigenia and Camptorrhiza and hence we studied the cytogenetics and phylogenetic placement of this species to ascertain its generic identity. Somatic chromosome count (2n = 22) and karyotypic features of C. indica are very similar to that of Iphigenia species. Molecular phylogenetic studies based on atpB-rbcL, rps16, trnL, and trnL-F regions showed that C. indica is nested within a lineage of Indian Iphigenia species. Thus, C. indica was reduced to a species of Iphigenia, i.e., I. ratnagirica. Camptorrhiza is now a monotypic genus restricted only to southern Africa. A key to the Indian Iphigenia species is provided. In addition, a new combination Wurmbea novae-zelandiae is proposed for Iphigenia novae-zelandiae

Two new species of Brachystelma Sims (Apocynaceae: Asclepiadoideae-Ceropegieae) from the Western Ghats of India

Two new species of Brachystelma: B. mahajanii Kambale & S. R. Yadav from Ebbanad, Nilgiri District, Tamil Nadu and B. vartakii Kambale & S. R. Yadav from Periya, Kasargod District, Kerala are described and illustrated

Cynanchum (Apocynaceae: Asclepiadoideae): A pantropical Asclepiadoid genus revisited

Cynanchum constitutes one of the very few Asclepiadoid genera that are distributed both in the Old and the New World. The present study of more than 100 species, based on Bayesian and maximum likelihood analysis of five chloroplast and four nuclear markers, resolves nine clades. No unambiguous morphological characters are associated with any particular Glade or a combination of several clades, so that a wide concept of Cynanchum seems the most appropriate taxonomic solution for the group. For this reason, several hitherto independent genera, Glossonema, Graphistemma, Holostemma, Metalepis, Metaplexis, Odontanthera, Pentarrhinum, Raphistemma and Seshagiria are included in Cynanchum. In addition, Adelostemma and Sichuania are subsumed under Cynanchum for morphological reasons. The necessary new combinations are made, resulting in twelve new species combinations, two new subspecies combinations, and two new names

Haplanthodes Kuntze 1903

Key to species of <i>Haplanthodes</i> <p> 1. Cladodes stout, spiny..................................................................................................................................................... <i>H</i>. <i>verticillata</i></p> <p>- Cladodes slender, not spiny................................................................................................................................................................2</p> <p> 2. Feathery hairs present only on the lower half of the cladode; calyx 1/2 the length of corolla; cladodes up to 1.8 cm long.......................................................................................................................................................................................................... <i>H</i>. <i>plumosa</i></p> <p>- Feathery hairs absent on the cladode; calyx 1/4 the length of corolla; cladodes up to 3 cm long.....................................................3</p> <p> 3. Ovary glabrous; bracts equal to length of calyx; cladodes 2–4 times longer than the length of corolla; seeds with micro-papillae......................................................................................................................................................................................... <i>H</i>. <i>tentaculata</i></p> <p> - Ovary hairy; bracts shorter than the length of calyx; cladodes equal or shorter than the length of corolla; seeds without micropapillae.................................................................................................................................................................. <i>H. neilgherryensis</i></p>Published as part of <i>Deshmukh, Pradip Vikram, Surveswaran, Siddharthan, Gore, Ramchandra Dnyanoba & Lekhak, Manoj Madhwanand, 2021, Taxonomic studies in the genus Haplanthodes (Acanthaceae), pp. 201-222 in Phytotaxa 516 (3)</i> on page 203, DOI: 10.11646/phytotaxa.516.3.1, <a href="http://zenodo.org/record/5372865">http://zenodo.org/record/5372865</a&gt

The complete plastome sequence of Gnetum ula (Gnetales: Gnetaceae)

This study reports the complete plastome sequence of Gnetum ula, a gymnosperm species of Gnetaceae (Gnetophyta). The plastome is 113 249 bp long. It has a quadripartite structure containing a pair of large inverted repeat regions of 19 772 bp each, a large single-copy region of 64 914 bp, and a small single-copy region of 8791 bp. One hundred sixteen genes were predicted in the plastome, including 68 protein-coding genes, eight ribosomal RNA genes, and 40 transfer RNA genes. The gene density is 1.024 (genes/kb). Similar to other known Gnetum plastomes, the G. ula plastome has lost 20 protein-coding genes commonly present in other seed plant plastomes. Our phylogenetic analyses indicate that the four sampled Gnetum species are monophyletic and that G. ula is close to the two other lianas rather than the only small tree species, G. gnemon. Our phylogenetic trees also indicate that gnetophytes have the fastest evolutionary rates among gymnosperms

Molecular phylogeny of Glyphochloa (Poaceae, Panicoideae), an endemic grass genus from the Western Ghats, India

The genus Glyphochloa (Poaceae: Panicoideae: Andropogoneae: Rottboellinae) is endemic to peninsular India and is distributed on lateritic plateaus of low and high altitude in and around Western Ghats and the Malabar Coast. The genus presumably originated and diversified in the Western Ghats. Species relationships in the genus Glyphochloa were deduced here based on molecular phylogenies inferred using nuclear ribosomal ITS sequences and plastid intergenic spacer regions (atpB-rbcL, trnT-trnL, trnL-trnF), and new observations were made of spikelet morphology, caryopsis morphology and meiotic chromosome counts. We observed two distinct clades of Glyphochloa s.l. One of these (group I') includes Ophiuros bombaiensis, and is characterized by a single-awned lower glume and a base chromosome number of 6; it grows in low elevation coastal areas. The other clade (group II') has a double-awned lower glume, a base chromosome number of 7, and is restricted to higher elevation lateritic plateaus; G. ratnagirica may belong to the group II clade, or may be a third distinct lineage in the genus. A sister-group relationship between group I and II taxa (with or without G. ratnagirica) is not well supported, although the genus is recovered as monophyletic in shortest trees inferred using ITS or concatenated plastid data. We present a key to species of Glyphochloa and make a new combination for O. bombaiensis

Reconstructing the macroevolutionary patterns of aphids (Hemiptera: Aphididae) using nuclear and mitochondrial DNA sequences

Aphids (Hemiptera: Aphidoidea: Aphididae) have distinctive features and significant variability in interesting biological traits. Aphididae comprises c. 5000 species distributed worldwide with a rapid diversification rate, which makes reliable phylogenetic reconstruction difficult as a framework for evolutionary inference. Despite several studies, the phylogenies of various subfamilies of Aphididae are not yet resolved, and their phylogenetic positions are still debated. Our study, based on two mitochondrial markers (COI and COII) and one nuclear marker (EF-1 alpha), provided confirmation of some of the discrepancies as well as concordances of previous work, and thus contributes to an understanding of the higher-level relationships of Aphididae. Analyses of the combined dataset produced a well-resolved phylogenetic tree in which the major ten subfamilies of aphids correspond well with their associations with host plants. Sister relationships were found between Aphidini and Macrosiphini (Hormaphidini + Nipponaphidini) and Cerataphidini, and Fordini and Pemphigini. Lachnini is the only non-monophyletic tribe and Lizeriinae, represented by Paoliella nirmalae, occupied the basal position in Aphididae. Molecular dating of divergence revealed that diversification among the tribes and subtribes occurred in the Late Cretaceous to Late Oligocene. Thus, our phylogenetic analysis provides further insights into understanding the higher-level relationships within Aphidoidea