Similarity In Habits Research Articles

Gypsophila yazdiana(Caryophyllaceae), a New Species from Iran

Gypsophila yazdiana Falat., F. Ghahrem. & Assadi (Caryophyllaceae, Caryophylloideae) is described here as a new species from central Iran and is assigned to Gypsophila L. sect. Paniculaeformes F. N. Williams. Despite the overall similarity in habit and shape of the leaves and inflorescence, it differs from the related species G. perfoliata L. by having the stems glabrous, the leaves glabrous and narrower, oblanceolate to narrowly lanceolate, to 1.5 cm wide, and the petals rounded at the apex. In G. perfoliata the stem is glandular pubescent in the lower half, the leaves are glandular pubescent, obovate or ovate-oblong, and up to 3.5 cm wide, and the petals are retuse at the apex.

Spiradiclis pengshuiensis (Ophiorrhizeae, Rubioideae), a new species from Chongqing, China.

Spiradiclis pengshuiensis Bo Pan & R. J. Wang (Rubiaceae) is described as a new species from Chongqing in SW China. It is morphologically compared with Spiradiclis pauciflora L. Wu & Q. R. Liu because of their similarities in habit, pubescent surface, small leaf laminas and subglobose capsules. Its conservation status is evaluated as “VU” according to the IUCN categories and criteria.

Melothria domingensis (Cucurbitaceae), an endangered Caribbean endemic, is a Cayaponia

The Neotropical genus Melothria (Benincaseae, Cucurbitaceae) is a small group of yellow- or white-flowered climbers with small to medium-sized fruits. In 1899, Alfred Cogniaux described a species from montane rainforest in Haiti as Melothria domingensis, presumably based on the overall similarity in habit, leaf shape, and fruit morphology of his incomplete herbarium material to other Central American Melothria species. Melothria domingensis is still rare in European and American herbaria and the species has never been studied in detail. We here present molecular and morphological analyses, which show that the species is misplaced in Melothria and instead belongs in the distantly related tribe Cucurbiteae in the genus Cayaponia. We illustrate the species, provide the formal transfer and an extended description, and discuss the phylogenetic, biogeographic and ecological implications, including the finding that most likely bee- and not bat-pollination is ancestral in Cayaponia.

The non-geniculate coralline algae Synarthrophyton eckloniae (Foslie) comb. nov. and S. magellanicum (Foslie) comb. nov. (Rhodophyta) in South Africa including comparison with relevant types

In continuing studies on the taxonomy of non-geniculate, coralline algae from South Africa, stipes of the kelp, Ecklonia maxima, in the subtidal zone of Western Cape Province, were frequently observed to be covered with rosy-pink encrusting coralline algae. The reproductive morphology and anatomy of these plants show that they belong to the subfamily Melobesioideae and the genus Synarthrophyton. The specimens agree closely with the holotype of Lithothamnion capense f. eckloniae described by Foslie on the basis of South African material. Synarthrophyton eckloniae is described in detail; the species appears to be endemic to Western Cape Province. Another crustose coralline alga from the subtidal zone of South Africa was found to be conspecific with a syntype of Lithothamnion magellanicum and the lectotype and isolectotype of Lithothamnion muelleri f. neglecta. These are now shown to conform to the generic concept of Synarthrophyton on the basis of their concordance with the characters of that genus. South African material of S. magellanicum is compared with the type specimen of Lithophyllum schmitzii with which it had been synonymized and it is concluded that the two species are distinct. It can be distinguished from type specimens of Lithothamnion lamellatum and L. chatamense, with which previous authors had suggested it might be conspecific, on the basis of anatomical characters, despite similarity in habit. The last two species have not been recorded in South Africa.

Genecological and isozyme studies in Senecio vernalis Waldst. & Kit. and S. vulgaris L. var. vulgaris (Asteraceae) from Central Europe and Israel

Summary Genecological evidence and evidence obtained from an isozyme survey suggest a considerable amount of intraspecific differentiation in Senecio vernalis . Plants of this species from Israel were found to differ strikingly from those of C European (German) origin in most of the traits investigated, e.g., in the possession of pronounced seed dormancy, which seems to be governed by a single gene, a shorter life cycle, lack of rosette growth correlated with stem elongation prior to budding, a larger number of smaller capitula with fewer (disc) florets, and an ephemeral habit with plants only flowering soon after the first winter rains. Both accessions achieved a similar reproductive potential by different means. Electrophoretic analysis of eleven isozyme loci using seven different enzyme systems demonstrated that S. vernalis from Israel and C Europe fit the general pattern that has emerged from plant isozyme studies involving presumed source populations and colonizers derived from these. Thus, the allelic diversity of C European S. vernalis represented a subset of the variation present in S. vernalis from Israel. Historical and ecological factors, interspecific hybridization, and the phylogenetic relationship between the two accessions are discussed as possible causes of the variation in isozyme patterns observed. It is evident that the study of exclusively C European material of S. vernalis by previous workers has concealed phenotypic similarities between Israeli S. vernalis and the closely related S. vulgaris var. vulgaris in speed of development, and probably also photoperiodic response, and several vegetative traits. The presence of pronounced seed dormancy and a strongly abbreviated life cycle in Mediterranean material of both S. vernalis and S. vulgaris var. vulgaris are considered major adaptations to environmental conditions imposed by the Mediterranean climate, leading to similarities in habit. The phylogenetic implications of the present observation of both isozyme and phenotypic variability are briefly discussed.

Jessea and Talamancalia, Two New Genera of the Senecioneae (Asteraceae) from Costa Rica and Panama

Jessea and Talamancalia, Two New Genera of the Senecioneae (Asteraceae) from Costa Rica and Panama

A New Combination in Graphistylis (Compositae)

The distinctive genus Graphistylis B. Nord. is endemic to Brazil (Nordenstam 1978; Jeffrey 1992), and is found in the montane regions of Minas Gerais, Parandt, Rio de Janeiro and Sio Paulo states. The distinctive penicillate style-arm appendages, auriculate basal anther appendages, glabrous achenes and habit have distinguished this group of taxa since Cabrera (1950) recognized them as a section under Senecio (Hind 1993). Hind (1993) has recently recognized seven species and provided a key to the genera of the tribe Senecioneae, highlighting the feature of the radiate capitula in the species then recognized; this study forms part of continuing research towards a revision of the genus Graphistylis. The description of the recently published Senecio serranus Zardini (Zardini 1992) suggested that this plant belonged to the genus Graphistylis B. Nord. on the basis of the conspicuously penicillate style-arms, together with the overall similarity in habit. Examination of isotype and paratype material of S. serranus confirmed that it is a discoid species unlike the other species in the genus Graphistylis (Nordenstam 1978). The following new combination is therefore proposed:

Revision del Genero Styphnolobium (Leguminosae: Papilionoideae: Sophoreae)

The genus Styphnolobium is recognized as a segregate from Sophora on the basis of habit, stipels, bracteoles, legume, and chromosome number. It is enlarged from four to nine species through the description of five species new to science: Styphnolobium burseroides, S. monteviridis, S. parviflorum, S. protantherum, and S. sporadicum. Two sections are recognized, one requiring the new combination section Oresbios. The genus is centered in the Mexican-Mesoamerican area. Through similarities in habit, bracteoles, and dehiscence of the legume, it is clearly most closely related to Calia

Zymurgia, a new genus of the Halymeniaceae (Gigartinales, Rhodophyta) from southeastern Australia

Abstract Zymurgia gen. nov. (Halymeniaceae, Rhodophyta), with the single species Zymurgia chondriopsidea (J. Agardh) comb. nov. (= Halymenia ? chondriopsidea J. Agardh), is proposed. The original description of Halymenia ? chondriopsidea was based on a single tetrasporangial plant from Tasmania. Unique features of the genus include orthostichously arranged periaxial cells on the axial filaments at the apices and non-ampullary carpogonial branches. Post-fertilization events and the structure of the auxiliary cell branches are typical of the Halymeniaceae. Because of similarities in habit, texture, thallus structure and the carpogonial apparatus, it is concluded that Zymurgia represents either evidence for a close phylogenetic relationship between the Dumontiaceae and the Halymeniaceae, two families previously considered to be only distantly related, or a parallel, independent convergence towards some anatomical features of relatively unspecialized members of the dumontiaceous tribe Dumontieae, such as Hyal...

Struggle for life most severe between individuals and varieties of the same species

As the species of the same genus usually have, though by no means invariably, much similarity in habits and constitution, and always in structure, the struggle will generally be more severe between them, if they come into competition with each other, than between the species of distinct genera. We see this in the recent extension over parts of the United States of one species of swallow having caused the decrease of another species. The recent increase of the missel‐thrush in parts of Scotland has caused the decrease of the song‐thrush. How frequently we hear of one species of rat taking the place of another species under the most different climates. In Russia the small Asiatic cockroach has everywhere driven before it its great congener. In Australia the imported hive‐bee is rapidly exterminating the small, stingless native bee. One species of charlock has been known to supplant another species; and so in other cases. We can dimly see why the competition should be most severe between allied forms, which fill nearly the same place in the economy of nature; but probably in no one case could we precisely say why one species has been victorious over another in the great battle of life….

MORELLIA HORTENSIA (WIEDEMANN), A NEW LIVESTOCK FLY IN AUSTRALIA

Morellia hortensia, a fly not previously known from Australia, was found to be infesting livestock over much of northern Australia. Dissections showed that blood was present in the gut more frequently than in another livestock-infesting fly, Musca fergusoni, and it is suggested that Morellia uses prestomal teeth on the proboscis to draw blood from soft tissue. Field observations were made on adults feeding on livestock, and breeding in cow dung, and the immature stages are briefly described and illustrated. The species shows similarities in habit to the face fly of North America, but is probably only a minor pest of livestock. The possible history of its introduction to Australia is discussed.

An Ecological Study of the Feeding Habits of the English Titmice

Problems of the interaction between predatory animals and the species whereon they feed may be attacked in two ways. When the predator species is sufficiently numerous and the prey is amenable to accurate sampling the advance may be direct. But when the predator is scarce or its foods are diverse; when the prey species are so inaccessibly or unevenly dispersed that they cannot be quantitatively surveyed, then indirect methods of investigation must be used. Early in 1947, at the request of the Agricultural Research Council, the Edward Grey Institute of Field Ornithology began an investigation of the dual problem of the influence of bird predation upon the numbers of the prey species and of the influence of the stocks of prey upon the population level of the carnivores. It was agreed that species of economic importance should not be studied, so that the work should not be done upon birds directly dependent on man's activities for a major part of their food supply. The species selected for study must be resident throughout the year, and must be abundant. Here a difficulty was found, for few bird species, even those usually described as 'common' or 'abundant' are represented in any habitat in such numbers that adequate sampling will not sensibly modify, or even destroy the stock in the course of the investigation. This difficulty in choice of species suitable for a direct approach was especially marked after the decimation of the stocks of so many passerine birds in the great frost of early 1947 (Ticehurst & Hartley 1948). It was therefore decided to make an indirect attack upon the problem by the application of a principle enunciated by Charles Darwin (1859): 'As the species of the same genus usually have, though by no means invariably, much similarity in habits and constitution, and always in structure, the struggle will generally be more severe between them, if they come into competition with each other, than between the species of distinct genera.' A group of closely related species, all reasonably abundant, was needed for work on the implication of this principle. In the English Midlands the Paridae (titmice) were an obvious choice. Four species were to be found regularly feeding in the same habitats: great tit, Parus major L.; blue tit, P. caeruleus L.; coal tit, P. ater L.; marsh tit, P. palustris L. Certain ecological conclusions could be drawn from the results of study of the feeding habits of four congeneric species living side by side. If no distinctions could be made between the foods, feeding places and feeding methods of the four species it might reasonably be assumed that food supply was not the factor limiting their numbers. Conversely, a measure of ecological separation between the species would justify the assumption of some degree of interspecific pressure. Lack