To be or not to be a valid genus: the systematic position of Ophyra R.‐D. revised (Diptera: Muscidae)

Ophyra Robineau‐Desvoidy is one of the better‐studied genera of the family Muscidae (Diptera). The larvae of species of this genus feed on highly decomposed organic matter of various origins, and may reveal predatory behaviour as they mature. These feeding habits, combined with the widespread distribution and close association with human dwellings of some species, give the genus commercial and medico‐legal importance. However, the systematic position of Ophyra has been a matter of debate for many years. Ophyra has been considered by muscid workers to be either a valid genus or a junior synonym of Hydrotaea Robineau‐Desvoidy. A lack of agreement about the systematic position of Ophyra has led to serious errors, particularly in the applied literature. Recent molecular and morphological studies provided contradictory information on the validity of the genus and its subfamilial classification. We revise the systematic position of Ophyra herein by means of molecular phylogenetic reconstruction. Our results are incongruent with opinions on the systematic position of Ophyra based on previously published molecular phylogenies, although they correspond with the concept of the genus based on adult morphology. All analyses of the concatenated dataset revealed Ophyra as monophyletic and placed within a paraphyletic Azeliini. Depending on the phylogenetic approach, Ophyra was placed within either a monophyletic, paraphyletic or polyphyletic Hydrotaea, yet always closely related to a certain group of species. We conclude that Ophyra, as currently defined, should not be considered a valid name, yet a detailed reconstruction of the genus Hydrotaea awaits future studies with greater increases in both taxon sampling and the number of molecular markers.     

Likelihood approximations of implied weights parsimony can be selected over the Mk model by the Akaike information criterion

A likelihood method that approximates the behaviour of implied weighting is described. This approach provides a likelihood perspective on several aspects of implied weighting, such as guidance for the choice of concavity values, a justification to use different concavities for different numbers of taxa, and a natural basis for extended implied weighting. In this approach, the number of free parameters in the estimation depends on C, the number of characters (in contrast to the standard Mk model, which estimates 2T–3 parameters for T taxa). Depending on the characteristics of the dataset, the likelihood obtained with this approach may in some cases be similar or superior to that of the Mk model, but with fewer parameters being adjusted. Because of that tradeoff, testing against the Mk model by means of the Akaike information criterion on a set of 182 morphological datasets indicated many cases (36) in which the likelihood approximation to implied weighting is the best method, from an information-theoretic point of view. Given that it is expected to produce (almost) the same results as this maximum-likelihood approximation, implied weighting can therefore be seen as a valid alternative to the Mk model often used for morphological datasets, on the basis of a criterion for model fit widely advocated by likelihoodists.     

A Bryophyte flora of Cornwall. II. Sphagna

Abstract

The taxonomy of Anomobryum julaceum and allied species with axillary bulbils in Europe and Asia is reviewed. A. concinnatum is regarded as a distinct species, occurring in W. and C. Europe, SW., N. and C. Asia and N. America. A. bavaricum has often been confused with A. concinnatum, but differs in its more numerous, small, reddish bulbils and in leaf shape; it is known only from the European Alps. The Asian A. nitidum also has numerous small reddish bulbils but it differs from A. bavaricum in leaf shape and bulbil form. A lectotype is designated for A. nitidum, of which A. gemmigerum and other nominal taxa are regarded as synonyms. Information is presented on geographical ranges and habitats of the four valid species.     

Notes on Plecoptera (19) Isoperla lugens (Klapalek, 1923), replaces I. alpicola Brinck, 1949

A male lectotype and several paralectotypes of Chloroperla lugens Klapálek, 1923 are designated. The species is transferred to genus Isoperla and is the valid name for Isoperla alpicola Brinck, 1949.     

A taxonomic review of the nivicolous species of myxomycetes described by Kowalski. I. Order Stemonitales

Five type specimens of species from the order Stemonitales proposed by Kowalski are re-examined. These are Comatricha fusiforme, Diacheopsis effusa, D. serpula, Lamproderma acanthosporum and L. disseminatum. SEM and LM micrographs of spores, capillitia and sporocarps are provided. Critical study of these type specimens supports Kowalski’s recognition of these taxa as good and valid species.     

Revision and typification of names in Canarian Sonchus (Asteraceae: Cichorieae) published by or based on material from E. R. Sventenius

In the present paper we analyse the validity and nomenclatural status of the names of 16 taxa (eight species, four interspecific hybrids, one subspecies and three varieties) in Macaronesian Sonchus described or collected by E. R. Sventenius. As there is much controversy regarding their validity, mainly concerning the proper indication of the types and their location, we conducted a general revision of exsiccata, collected by Sventenius and kept at ORT, GB and BC, in order to locate possible type material. As a result, we located five holotypes, designated six lectotypes (four of which are illustrations), two neotypes and two epitypes, and located six isotypes and one paratype. We propose accepting the validity of most of Sventenius's names in the group with the exception of those whose protologue includes more than one gathering. Because except for S. ortunoi Svent. the taxa have valid names subsequently published by L. Boulos, we introduce a valid name for S. ortunoi here. Furthermore, we indicate legitimate names in the more widely circumscribed Sonchus that is now recognized based on recent phylogenetic reconstructions; in addition, we introduce the new combinations S.×rupicola (Svent.) A. Santos & Mejías and S.×decipiens (Svent.) A. Santos & Mejías.     

Sequence Analysis of 18S-28S rRNA Spacer Regions from Saccharomyces kunashirensis, S. martiniae, S. rosinii, and S. transvaalensis

Sequences of two internal transcribed spacer regions between 18S and 28S rRNA for recently described yeasts species, Saccharomyces kunashirensis, S. martiniae, S. rosinii, and S. transvaalensis, were determined to assess their phylogenetic relationship to the other Saccharomyces species. In the two phylogenetic trees constructed by the neighbor-joining method, independent branches reflected that delimitation of the four new species was valid. Received: 17 June 1998 / Accepted: 7 August 1998     

THE GENUS PLATOMA (GIGARTINALES,RHODOPHYTA) WITH A DESCRIPTION OF P. ABBOTTIANA SP. NOV.1

Platoma abbottiana (Gymnophlaeaceae; Gigartinales), a new species of benthic red algae, is described from Isla Mejía and is the second member of this genus reported from the Gulf of California, Mexico. Vegetative anatomy and reproductive details of the carpogonial and auxiliary cell branches of the new species are described and illustrated. Geographical distributions of the seven previously described Platoma species are given. Their distinguishing morphological characteristics are compared to those of the new species. The correct time and place of valid publication of the generic name, Platoma, and some of its binomials are discussed.     

应恢复赤车属头序赤车组和头序赤车

头序赤车的特征在于其具花序托和总苞的雌头状花序,根据此一特征即可将它与赤车属的其它所有种区别开。因此,在2002年被错误归并为异名的此赤车属进化种,以及根据其建立的单种进化组头序赤车组在该文中予以恢复。     

A new species of Genus Triplophysa (Nemacheilinae: Balitoridae), Triplophysa longipectoralis sp. nov, from Guangxi, China

A new species, Triplophysa longipectoralis, is described from Liujiang River, Guangxi, China. The new species is distinguished from other species of Triplophysa by the following combination of characters: pectoral fin highly developed, reaching beyond pelvic-fin origin; eyes present and vestigial; body covered with scales; dorsal and lateral sides of head and body mottled with blotches; dorsal fin emarginate; caudal fin forked; anus close to anal-fin origin. A key to all valid species of Triplophysa in Xijiang River water system is provided. Chen and Yang contributed equally to this paper.     

VASCULAR CAMBIUM AND WOOD DEVELOPMENT IN CARBONIFEROUS PLANTS. I. LEPIDODENDRALES

Patterns of activity in the vascular cambium of Carboniferous arborescent lycopods (Paralycopodites and Stigmaria) were studied by analysis of serial tangential sections of the secondary xylem. The analysis assumes that cell patterns in the wood accurately reflect those of the corresponding cambium. An evaluation using indirect evidence indicates that the assumption is valid as far as can be determined from comparison with living plants. The tracheids of the secondary xylem enlarge in a centrifugal pattern, suggesting a progressive enlargement of the fusiform initials. There is no evidence of periodic anticlinal division of these initials, and it is proposed that the increase in cambial circumference was accommodated primarily by an increase in fusiform initial size. In some axes with abundant secondary xylem there is evidence that isolated initials or groups of initials sporadically subdivided to form numerous, spindle-shaped meristematic cells. Some of these cells subsequently developed into typical cambial initials. Tissues presumably formed during the cessation of cambial growth in Lepidodendron and Stigmaria are described; the structure of the tissues is suggestive of a postmeristematic parenchymatous sheath. It is concluded that cambial activity in these arborescent cryptogams was clearly different from that of modern seed plants, further attesting to the distinctive nature of this ancient group.     

Amphibians as definitive hosts for pentastomids: Raillietiella bufonis n.sp. from Bufo lemur in Puerto Rico and a reassessment of Raillietiella indica Gedoelst, 1921

Summary A new species of a cephalobaenid pentastomid infecting the lungs of a toad, Bufo lemur, from Puerto Rico is described. The single infection comprises all stages from infective larvae to mature males and females and therefore we consider the toad to be a definitive host. We reassess the evidence concerning Raillietiella indica Gedoelst, 1921, another raillietiellid from the lungs of an Indian toad, B. melanostictus which, hitherto, has been considered by most authors an immature stage from an intermediate host. It now appears that the type specimen was probably a gravid female and that R. indica is a valid species which also matures in a toad. Thus amphibians are established as a new class of definitive hosts for pentastomids. ac]19820218     

Arnoglossus macrolophus Alcock (Pleuronectiformes: Bothidae); a valid species distinct fromA. tapeinosomus (Bleeker)

The holotype of a bothid flounder,Arnoglossus tapeinosomus (Bleeker, 1866), was re-examined and found to bear none of the diagnostic characters ascribed by many authors to the species. In addition, the shape of the prevomer was clearly different between the holotype and 18 specimens supposedly“A. tapeinosomus.” A. macrolophus Alcock, 1889, which was synonymized underA. tapeinosomus by Weber and de Beaufort (1929), is considered as a valid replacement name for“A. tapeinosomus,” because of the elongated anterior rays in the dorsal fin and a large, dark spot on the posterior dorsal and anal fin bases.A. tapeinosomus is redescribed from the holotype.     

Comparative ecophysiology ofChrysanthemum pacificum Nakai andsolidago altissima L. 1. whyS. altissima cannot be established on the seashore

A fieldsurvey was made to elucidate whether salt spray is a major factor in preventing a common inland weed,Solidago altissima, from being established on the seashore of Boso Peninsula. Seasonal changes in the intensity of salt spray, sodium content in the soil water and soil water contents were measured at the seashore and inland. Seeds ofS. altissima were sown at both sites with those of a common maritime species,Chrysanthemum pacificum. The number of surviving shoots of the seedlings were periodically counted for 1 year. The intensity of the salt spray, sodium content and water contents of the soil on the seashore fluctuated seasonally. There were some periods when the intensity of salt spray was comparable to that of the inland site. Most of theS. altissima seedlings survived at the inland site. AllS. altissima seedlings germinated at the seashore were completely eliminated. The death rate ofS altissima seedlings at the seashore was not constant. Ninety-five percent of theS. altissima seedling in total died out during the four periods of intensive salt spray. The death rate ofC. pacificum seedlings on the seashore was not especially high during those periods. Correlation between seasonal changes in the death rate ofS. altissima seedlings and the sodium content or water content of the soil was low. These results indicate that intensive salt spray, intermittently blown in from the sea, is one of the most critical environmental factors that eliminatesS. altissima from the seashore.     

Assimilation of liquid hydrocarbon by microorganisms. II. Growth kinetics

The growth kinetics of a microorganism with high affinity for liquid hydrocarbon which has a low solubility in water was investigated for Candida intermedia IFO 0761 in our previous work.⁶ The microorganism contained a hydrocarbon pool in and/or on the cell. The transfer of water-soluble substrates to the cell was not the rate-limiting step in the growth of C. intermedia accompanied by clump formation with liquid hydrocarbon. The operating conditions necessary for the oxygen supply for the growth were adequate for the growth of C. intermedia on n-tetradecane. The saturation kinetics was valid for the specific growth rate of C. intermedia and specific concentration of hydrocarbon per unit cell mass; the specific growth rate was expressed by the following equation:      

The taxonomy of the family Paramphistomidae Fischoeder, 1901 with special reference to the morphology of species occurring in ruminants. VIII. The genera Stephanopharynx Fischoeder, 1901 and Balanorchis Fischoeder, 1901

Summary Only Stephanopharynx compactus Fischoeder, 1901 is considered valid under the genus Stephanopharynx Fischoeder, 1901 and S. secundus Stunkard, 1929 and S. coilos Dollfus, 1963 are regarded as its synonyms. The species is redescribed and illustrated based on new material and scanning electron photomicrographs of its tegumental surfaces and the internal surface of its pharyngeal pouch are provided. Balanorchis anastrophus Fischoeder, 1901, the one and only species of the genus Balanorchis Fischoeder, 1901 is redescribed and illustrated. Photomicrographs of its tegumental surfaces as revealed by scanning electron microscopy are given. Additional information on Bilatorchis papillogenitalis Eduardo, 1980 is included. Part of a thesis approved by the University of London for the award of the Ph.D. degree. Part of a thesis approved by the University of London for the award of the Ph.D. degree.     

Studies on Plasmodium Ookinetes. 1. Isolation and Concentration from Mosquito Midguts*

SYNOPSIS. In a method for isolating a relatively clean suspension of concentrated Plasmodium berghei ookinetes from infected midguts of Anopheles stephensi at appropriate times after the infective blood meal, the ookinetes are freed from the midguts by enzymatic digestion, and then concentrated by means of a BSA/renografin gradient. The mean number of ookinetes recovered/midgut was 152. More than 95% of the recovered ookinetes were viable by the criteria of motility, incorporation of adenosine and leucine, and appearance on light and electron microscopic examination. Trypan blue exclusion was not a valid criterion for viability. These ookinetes were not useful for in vitro studies of further development due to the presence of contaminating microorganisms. Our attempts to determine their potential for further development in vivo have similarly not been successful. Nevertheless, our ability to obtain large numbers of ookinetes at defined times during development now permits further studies on their structure, biochemistry, and physiology, as well as comparison with ookinetes formed in vitro.