Phytotaxa

We have counted the currently known, described and accepted number of plant species as ca 374,000, of which approximately 308,312 are vascular plants, with 295,383 flowering plants (angiosperms; monocots: 74,273; eudicots: 210,008). Global numbers of smaller plant groups are as follows: algae ca 44,000, liverworts ca 9,000, hornworts ca 225, mosses 12,700, lycopods 1,290, ferns 10,560 and gymnosperms 1,079. Phytotaxa is currently contributing more than a quarter of the ca 2000 species that are described every year, showing that it has become a major contributor to the dissemination of new species discovery. However, the rate of discovery is slowing down, due to reduction in financial and scientific support for fundamental natural history studies.

An entomogenous taxon, associated with larvae of Phassus nodus (Hepialidae) collected from Xuefeng Mountains, Hunan Province, China, was found to be a new species, Ophiocordyceps xuefengensis sp. nov. It differs from similar species in having long stromata, without a sterile apex, narrow asci, long ascospores and by its occurrence on Phassus nodus in living root or trunk of Clerodendrum cyrtophyllum. Combined sequence data from the 5.8S-ITS rDNA, nrSSU, EF-1α, and RPB1 gene loci also confirmed the distinctiveness of this new species. It is presently the world’s largest known Cordyceps sensu lato species. 

Stephanocha nom. nov. (Silicoflagellata, Dictyochophyceae) is herein proposed as a replacement name for the illegitimate genus name Distephanus, which is a later homonym of Distephanus, a flowering plant. The old generic description is emended, with S. rotunda as the designated type, and new combinations are made for all bona fide silicoflagellate taxa previously assigned (including those tentatively assigned) to Distephanus, except most already transferred to Distephanopsis.

Hybridization and polyploidization appear to be ubiquitous in the evolution of Chenopodium s.s., but the origin and the evolutionary history of the polyploid chenopods is still poorly understood. Phylogenetic analyses of DNA sequences of nrITS, four plastid regions, and 5S rDNA spacer region (NTS) of five Eurasian hexaploid chenopods (2n = 6x = 54), C. album, C. giganteum, C. pedunculare C. formosanum and C. opulifolium, and their diploid and tetraploid relatives as well as genomic in situ hybridization (GISH) indicate their allohexaploid origin. The origin of all the analyzed hexaploids have been inferred to have involved B-genome diploid. The identity of the other parent/parents is more elusive. In the case of C. album, C. giganteum and C. pedunculare the second maternal parent seems to be similar to extant C. strictum or C. striatiforme or Asian diploids (e.g. C. acuminatum). In genomes of allohexaploid C. album, C. giganteum and C. pedunculare half of the rDNA were located in the chromosomes of B-subgenome. The remaining rDNA loci were placed in chromosomes originating from the other parent/parents. Although 35S rDNA loci inherited from two parental species seems to be present in these hexaploids, only one ribotype of nrITS was detected.

The new species Asterochloris sejongensis sp. nov. has been collected from four localities of King George Island, Antarctica, and is described as a phycobiont of the lichen species Cladonia pyxidata and Sphaerophorus globosus. This discovery is based on morphological and molecular data obtained using light microscopy, confocal laser microscopy, transmission electron microscopy, and two molecular markers; nuclear internal transcribed spacer (ITS) rDNA and actin genes. This species is characterized by five unique hemi-CBCs in the nuclear ITS transcripts, deeply lobed and echinulate chloroplasts (depending on the life stage), and two rows of pyrenoglobuli associated with two thylakoid envelopes. A molecular phylogenetic analysis of the ITS and actin gene sequences indicated that this new species is closely related to A. woessiae and forms a distinct well-supported lineage with the genus.

Two new species of the red algal genus Hypnea (Gigartinales) are described for the southeastern coast of Brazil based on three molecular markers (COI-5P, rbcL and UPA), detailed morphological analysis, and comparison with closely related species. These species were named H. wynnei Nauer, Cassano & M.C. Oliveira and H. yokoyana Nauer, Cassano & M.C. Oliveira. Hypnea wynnei is characterized primarily by its reduced size, sub-erect tufts with few lateral branches and entangled basal portion, a thallus that is flattened only at the apical portions, and tetrasporangial sori developed only at apical portions of the branchlets. Hypnea yokoyana is characterized by its larger thallus, profuse branching, entirely terete axes, larger diameter of the main axes, and lack of entangling at its base. The molecular data support the conclusion that H. wynnei and H. yokoyana are distinct from other Hypnea species and are distantly related to Hypnea from the Brazilian coast.

Hygrochilus and Sedirea are genera of orchids with only three species endemic to Asia. An analysis of ITS and five plastid regions using parsimony, maximum likelihood, and Bayesian methods obtain clear evidence that Sedirea is nested within and should be considered synonymous with Hygrochilus. We adopt a broadly defined Hygrochilus characterized by possession of four pollinia. A new combination, namely, Hygrochilus japonica, and a new species, namely, Hygrochilus tsii (Orchidaceae: Epidedroideae: Aeridinae), are proposed.

Eriosema grearii, a new species for the genus (Leguminosae, Papilionoideae, Phaseoleae, Cajaninae), is described and illustrated. Similar to E. heterophyllum, it differs from it morphologically by the free (vs. joined) stipules, lax flowers distributed along the inflorescence axis (vs. congested and concentrated at its apex), inflorescences not opposite to the leaves (vs. opposite), and leaflets with secretory cells at the base of trichomes (vs. absence of secretory cells at the base of trichomes). A survey of the leaflet secretory structures revealed that E. grearii has distinct secretory structures, referred here as secretory-base trichomes, and reported for the first time for the Phaseoleae tribe. An identification key for the Eriosema species in Mato Grosso do Sul, where the new species occurs, is provided.

Eriosema tozziae, a new species of Leguminosae (Papilionoideae, Phaseoleae, Cajaninae) from Minas Gerais is described and illustrated. Similar to E. defoliatum, it differs morphologically from the latter by the persistent leaves in the reproductive phase (vs. caducous in E. defoliatum) and the shorter inflorescences (10–13 cm long vs. 15–30 cm long in E. defoliatum). An identification key for the Eriosema species in Minas Gerais is also provided.