A taxonomic reassessment of Viburnum (Adoxaceae) in the Azores

The taxonomic status of the Azorean endemic Viburnum tinus subsp. subcordatum is reassessed, using morphological characters and new molecular data from the ITS region and the trnK intron. A survey of morphological variation supports the recognition of V. tinus subsp. subcordatum as distinct from V. tinus subsp. tinus and the Canary endemic V. rugosum (formerly known as V. tinus subsp. rigidum) based on leaf shape, the shape of the leaf base and apex, the sub-entire and revolute leaf margins, blistered upper leaf surfaces, trichome density and type, and fruit size. Molecular data also confirm this distinctiveness within section Tinus. Taken together, our morphological and genetic data presented in this paper support the recognition of the Azorean taxon at the species level under the name of Viburnum treleasei. A description of the species is provided and nomenclatural issues relating to the two Macaronesian Viburnum taxa are discussed.

A phylogenetic analysis of the Cryptocarya group (Lauraceae), and relationships of Dahlgrenodendron, Sinopora, Triadodaphne, and Yasunia

A phylogenetic analysis based on nuclear ITS and plastid trnK intron sequences confirms that Dahlgrenodendron, Sinopora, Triadodaphne, and Yasunia are members of the Cryptocarya group, as expected from morphology. Dahlgrenodendron from South Africa is sister to Aspidostemon from Madagascar. Triadodaphne inaequitepala is nested within Endiandra (both from Australasia), and Yasunia from South America is nested among South American Beilschmiedia species. Sinopora is a member of the Beilschmiedia clade, but its precise position is still uncertain. Among large genera of the group, Cryptocarya is clearly monophyletic, and Endiandra appears to be as well, if T. inaequitepala is included. Beilschmiedia is paraphyletic with respect to (at least) Potameia and Yasunia. Most well-supported clades within genera are geographically homogeneous, except a clade including the Chilean Cryptocarya alba and two New Caledonian species. Both Beilschmiedia and Cryptocarya have reached the Americas more than once. Four-locular anthers are plesiomorphic in the Cryptocarya group; two-locular anthers have arisen by fusion of the two pollen sacs of a theca. In the plesiomorphic fruit type, the ovary is completely enclosed in receptacular tissue; a superior fruit, seated free on its pedicel, is a synapomorphy of the Beilschmiedia clade.

Molecular phylogenetics of mormolyca (orchidaceae: maxillariinae) based on combined molecular data sets

The Neotropical orchid genus Mormolyca Fenzl, as currently circumscribed, encompasses a diverse group of ca. 27species. Many of these were included traditionally in Maxillaria sect. Rufescens, when similarity of floral morphology was considered foremost in their classification rather than the evolutionary history of the taxa. In order to begin revising species delimitation and clarifying the evolution and biology of the genus, we present a phylogenetic hypothesis using sequence data from five plastid loci (rpoC1, matK gene and flanking trnK intron, atpB-rbcL intergenic spacer, and the 3’ portion of ycf1) and the nuclear ribosomal internal and external transcribed spacers (ITS, ETS). Resulting trees using both Bayesian and parsimony inference are congruent with each other, and generally well resolved. Based on current level of sampling across Maxillariinae, these molecular data support the monophyly of Mormolyca and shed light on the interspecific phylogenetic patterns within the genus. These include an early divergent paraphyletic grade of Mormolyca species successively sister to a clade with at least two definable subclades within. The latter are characterized by two different flower morphologies that are likely related to their pollination systems. Although not all relationships within the genus are fully resolved or supported, these results offer a first glimpse into the phylogeny of a small group of epiphytic orchids characterized by an unusually high level of variable vegetative characters, floral fragrance profiles, and pollination systems.

Phylogenetic analysis of the subtribe Chloraeinae (Orchidaceae): a preliminary approach based on three chloroplast markers

The systematic position and relationships between some South American terrestrial orchids, such as Bipinnula Comm. ex Juss., Chloraea Lindl., Gavilea Poepp. and Geoblasta Barb. Rodr., is unclear. These four genera have been grouped in the subtribe Chloraeinae by several authors. Previous phylogenetic studies of the group have included only a few species of Chloraea and Gavilea and not of Bipinnula or Geoblasta. Relationships among these four genera were explored and the monophyly of the subtribe Chloraeinae and the genera Chloraea and Gavilea were tested in this contribution. Molecular phylogenetic analyses were conducted, using the following three chloroplast markers: the matK–trnK intron, the atpB–rbcL spacer and the rpoC1 gene. Sequences were analysed under maximum parsimony and Bayesian inference. In all the analyses, Bipinnula, Chloraea, Gavilea and Geoblasta were grouped in a clade with high support, where Bipinnula, Geoblasta and Gavilea were nested inside Chloraea. Consequently, Chloraea was paraphyletic, whereas Gavilea turned out to be monophyletic with high values of support. The other species of tribe Cranichideae appeared as sister groups of the Chloraeinae. A more exhaustive taxonomic sampling is needed to resolve the systematic placement of the subtribe Chloraeinae and the internal relationships between the genera and species that form it.