Search

The genus Siphoptychium is resurrected on the basis of comparative morphology and phylogeny of partial nuc 18S rDNA (18S) and translation elongation factor 1-alpha (EF1A) nucleotide sequences. The genus is characterized by the firm upper surface of the pseudoaethalium, accreted but easily separable sporothecae, a tubular or fibrous columella, and spores with a reticulate ornamentation consisting of 7-9 meshes across the diameter. In addition to the currently known single species S. casparyi (= Tubifera casparyi), two new members of Siphoptychium are described: S. violaceum from coniferous forests of Europe, east Asia, and southeast Asia, and S. reticulatum from temperate and subarctic regions of North America and alpine regions of Europe. A second genus, Thecotubifera, is described to accommodate Tubifera dictyoderma. The fruiting body of this species is transitional between a pseudoaethalium and a true aethalium. It is covered by a contiguous membranous cortex formed by the fused tips of the sporothecae, a feature typical for aethalia. However, the inner portions of sporothecae remain discernible, a feature more typical for pseudoaethalia. Columellae of Th. dictyoderma are formed by perforated plates, and the spores have a reticulate ornamentation consisting of 2-5 meshes across the diameter. For Th. dictyoderma, we could confirm records only for tropical regions and Japan, whereas all studied European specimens, including those mentioned in current monographs, represent species of Siphoptychium.

The genus

A new species of myxomycete, Perichaena longipes, is described from 56 sporocarp specimens that appeared in moist chamber cultures prepared with samples of decaying plant materials collected in Panama, Costa Rica and Brazil. This new species is distinguished from the morphologically similar species P. pedata on the basis of the much longer stipe, lighter peridium and the unique ornamentation of the capillitium. The nuc 18S ribosomal DNA sequences obtained from four specimens of P. longipes support the distinction of this new taxon and its separation from P. pedata. Furthermore, maximum likelihood phylogeny supports earlier evidence that species currently within the genus Perichaena do not form a monophyletic clade. Instead they appear to form three separate branches within the bright-spored clade. The first clade includes P. longipes together with several species of Trichia and Metatrichia, the second includes P. pedata and P. chrysosperma, and the third clade is composed of P. corticalis, P. depressa and P. luteola.

Based on a morphological investigation of a series of specimens collected in New South Wales and Tasmania and a phylogeny constructed with partial 18S ribosomal RNA gene sequences, we describe a new species Alwisia lloydiae; the fourth species within the recently revalidated genus Alwisia. This new species is characterized by short ovate sporothecae with mostly free stalks, morphologically resembling the recently described A. morula. However, the new species possesses a tubular capillitium that suggests an affinity with A. bombarda. The capillitium of the new species is ornamented with globular warts, and this feature separates it from all other members of the genus.

Based on morphological investigations and a phylogeny constructed with partial sequences of the SSU rDNA gene, we revalidate the genus Alwisia and propose the combination Alwisia bombarda Berk. & Broome to be used against Tubifera bombarda (Berk. & Broome) G.W. Martin. Two new species, Alwisia morula and A. repens, are described based on material collected respectively in Costa Rica and Australia. Both new species lack a capillitium and possess individually stalked subspherical sporothecae. Alwisia repens differs from A. morula by its procumbent stalks and iridescent peridium. A comparison of 83 sequences of species in the genera Lycogala, Reticularia and Tubifera with a recent two-gene phylogeny of the bright-spored myxomycetes resulted in a similar topology of both Bayesian and maximum likelihood trees and placed A. bombarda, A. morula and A. repens in one well delimited clade within Reticulariaceae. Universidad de Costa Rica/[VI-731-B2-224]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ingeniería::Instituto Investigaciones en Ingeniería (INII)