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Recent advances in molecular phylogenetics in the family Convolvulaceae Juss. (particularly in formerly recognized tribe Merremieae) have brought new insights on generic delimitation. Therefore, many species were transferred across genera to accommodate the new classification. However, additional morphological and molecular analyses are still needed to address the affinities and position of some species formerly included in Merremia Dennst. ex Endl.s.l. and allied genera. In this study, we provide a phylogenetic framework for the placement of Indian species in a new generic arrangement and to address the status of doubtful distinct species. Distimake rhyncorhiza (Dalzell) A.R. Simões & Staples is proved to have its place in Distimake Raf., while Operculina tansaensis Santapau & Patel is validated as a distinct species from O. turpethum (L.) Silva Manso. A nomenclatural clarification for the misuse of the name "Merremia gangetica (L.) Cufod". in India is provided, with an encouragement to use the correct name Merremia emarginata (Burm.f.) Hallier f. The addition of the Indian species to the molecular phylogeny suggests the possible non-monophyly of Camonea Raf., and a new placement for Camonea vitifolia (Burm.f.) A.R. Simões & Staples, albeit still weakly supported. We have provided morphological descriptions, distribution maps and notes on nomenclature. [ABSTRACT FROM AUTHOR]

is a highly diverse genus in Brazil, particularly the south-eastern region, and most especially in the Atlantic Forest. Recent phylogenetic studies have helped clarify the intricate subgeneric classification of the genus, although some species remain to be sampled, and further studies are necessary to ascertain their systematic placement in the genus. Here, a palynological description of nine species occurring in a patch of Atlantic Forest, in the State of São Paulo, is provided. Three of these have not yet been sampled in molecular studies. The pollen of D. tauriglossum had never been characterised before. Dioscorea pollen are spheroidal to ellipsoidal, small to medium in size (the larger dimensions in D. dodecaneura and the smaller in D. amaranthoides), with disulculate aperture. The pollen wall ornamentation contributed to the segregation of two species – psilate-perforate (D. altissima, syn. D. choncrocarpa) and rugulate-perforate (D. monadelpha), as well as the separation of the other seven species in two groups – microreticulate (D. dodecaneura, D. multiflora, D. tauriglossum), and striate (D. amaranthoides, D. laxiflora, D. olfersiana, D. trilinguis). Systematic implications of the palynological variation found are discussed under the light of recent molecular phylogenetic studies. [ABSTRACT FROM AUTHOR]

Operculina is a pantropical genus of 14 species, perhaps one of the most stable in taxonomic delimitation in Convolvulaceae. Its operculate-capsular fruit is distinctive and unique in the family, and shared by all species it comprises, despite great variation in other macromorphological traits. Recent molecular phylogenetic results have demonstrated Operculina is monophyletic with high support, re-enforcing the generic concept. However, revisionary studies of its taxonomy and morphology are limited, and information about its species is mostly scattered in regional works. Particularly in palynology, there are few studies that have included this genus, and usually only the most common species O. turpethum. Here, we provide an overview of the palynological diversity in 12 Operculina species and discuss the evolution and taxonomic relevance of aperture heteromorphism in this genus. [ABSTRACT FROM AUTHOR]