New data on the systematics of the Limnocytheridae (Ostracoda,Cytheracea)

A new grouping of genera having fossil as well as recent representatives of the family Limnocytheridae (Ostracoda, Cytheracea) is proposed using morphological characteristics of the appendages, of the shell and of the evolutionary trends observed in this family.     

Thermal biology of zebrafish (Danio rerio)

Zebrafish has become one of the most important animal models in research. Most of the variables studied using zebrafish are influenced by water temperature. The objective of this review was to analyze the published data on the thermal biology of the zebrafish. The paper first provides a brief introduction to zebrafish ecology and thermal tolerance, and continues with a review of the influence of temperature on several physiological variables, including development, growth, metabolism, reproduction, behavior, circadian biology and toxicology. Although a number of papers have already studied the effects of temperature on the zebrafish biology, knowledge in this field is still scarce, especially compared with other model organisms such as the rat, and therefore further research should be encouraged.     

Flowers and floral biology of the holy grasses (Hierochloe and Anthoxanthum: Aveneae,Gramineae)

Trifloreted spikelets in species of Anthoxanthum and of Hierochloe are united by the syndrome of two lower male or neuter florets and a differentiated third floret, perfect, bistaminate, and protogynous. Differences in presentation of the floral organs from the third anthoecium separate the genera. Anthers in Anthoxanthum, longer than the f3 anthoecium, keep it open until they migrate on elongating filaments, following behind the protogynous stigma-styles. Both emerge near the apex of the upper glume which tightly encloses all three florets. In Hierochloe the uppermost anthoecium is closed over the androecium and gynoecium until lodicule-controlled anthesis when stigma-styles are exserted unhindered by glumes, and the anthers are exserted later on long filaments from the chasmogamous lower florets. In Hierochloe triandrous lower florets are constant. In Anthoxanthum the two lower florets are neuter in Eurasian species, but in species in Africa, Asia, and Malesia, sometimes f1 florets are also staminate, and very exceptionally both florets present stamens. These reflect a sexual variability in Anthoxanthum unknown in Hierochloe. Data from flowers of 30 species of Hierochloe and 17 species of Anthoxanthum are tabulated; included are ratios of f3 anthers:anthoecium and stigma-styles:the upper glume, G2, two ratios which most reliably reflect the intergeneric floral patterns. Pathways to those varied floral systems are outlined. A sectional taxonomy is proposed for Hierochloe: Sect. Hierochloe autonymum; Sect. nova Monoecia for species in South America where monoecism occurs in all taxa. Andromonoecism is the predominant sexual system in boreal and austral species of Hierochloe, but is interrupted by apomixis in northern Europe.     

Comparative floral structure and systematics in the Asian palm genus Rhapis (Arecaceae,Coryphoideae)

A comparative study of the floral structure in the species of the genus Rhapis (Arecaceae, Coryphoideae, Rhapidinae) is presented. Flowers are mainly unisexual, with three sepals, three petals, 6 stamens or staminodes and three carpels or carpellodes. Some evidences of basal congenital and apical postgenital fusion of the carpels, first time reported in the genus, were observed in the gynoecium. Ovules are basally attached and crassinucellate; they appear to be slightly anatropous. The morphology of the filaments suggests a division of the species into two groups: Rhapis excelsa and R. subtilis exhibit thick and keeled filaments, whereas R. gracilis, R. humilis, R. laosensis, R. micrantha and R. multifida have slender, non-keeled filaments. Relationships of Rhapis with the rest of the genera of Rhapidinae are inferred on the light of floral structure.     

The genus Anvillea (Compositae)

The genus Anvillea (Compositae–Inuleae–Inulinae) is found to contain two species which occur in N Africa and the Middle East. Anvilleina Maire is reduced to a synonym of Anvillea and the following two new combinations are made: A. platycarpa (Maire) A. Anderb. and A. garcinii (Burm. f.) DC. ssp. radiata (Coss. & Dur.) A. Anderb. The chromosome number 2n = 14 of A. garcinii ssp. radiata is reported.     

Transformationalism,taxism, and developmental biology in systematics

Issues concerning transformational and taxic comparisons are central to understanding the impact of the recent proliferation of molecular developmental data on evolutionary biology. More importantly, an understanding of taxism and transformationalism in comparative biology is critical to assessing the impact of the recent developmental data on systematic theory and practice. We examine the philosophical and practical aspects of the transformational approach and the relevance of this approach to recent molecular-based developmental data. We also examine the theoretical basis of the taxic approach to molecular developmental data and suggest that developmental data are perfectly amenable to the taxic approach. Two recent examples from the molecular developmental biology literature--the evolution of insect wings and the evolution of dorsal ventral inversion in vertebrates and invertebrates--are used to compare the taxic and transformational approaches. We conclude that the transformational approach is entirely appropriate for ontogenetic studies and furthermore can serve as an excellent source of hypotheses about the evolution of characters. However, the taxic approach is the ultimate arbiter of these hypotheses.     

Flavonoid patterns and systematics in Eleusine

A survey of leaf flavonoids was conducted on Eleusine coracana ssp. coracana and ssp. africana, E. indica, E. multiflora, E. tristachya, E. floccifolia, and E. compressa. Twenty phenolic compounds were detected. Those identified were: orientin, isoorientin, vitexin, isovitexin, saponarin, violanthin, lucenin-1, and tricin. The study revealed a general generic flavonoid pattern except for E. compressa, which occupies an isolated position in Eleusine. Flavonoids of the perennial E. floccifolia and the annuals E. multiflora and E. tristachya are markedly different from those of cultivated E. coracana, suggesting that these species are only distantly related to the crop. The morphologically well defined E. coracana—africana—indica group also forms a unit in respect of flavonoids. Subspecies africana exhibits a higher flavonoid similarity to ssp. coracana (finger millet) than does E. indica. The weedy race of ssp. africana usually combines flavonoids of both the wild and domesticated subspecies. The flavonoid pattern of the dedza race of ssp.africana is identical to that of finger millet, suggesting either a direct origin of the crop from this race, or extensive introgression from the crop into ssp. africana. A lack of qualitative differences in flavonoids between cultivated races of finger millet is indicative of the genetic stability of these compounds. The flavonoid data confirms the domestication of finger millet from ssp. africana.     

Pollination biology of Indotristicha ramosissima (Podostemaceae: Tristichoideae)

Floral morphology, phenology and mode of pollination have been studied in Indotristicha ramosissima (Wt.) van Royen. Although the plants are submerged, self-pollination (autogamy) occurs above water. This is aided by considerable elongation of the pedicel (20 mm) prior to pollination. The filaments of the stamens also elongate rapidly (∼6.5 mm/h) before and after pollination. The flowers are typically trimerous. Each anther contains 1743 ± 187 pollen grains. These are spherical, multiporate, 3-celled and ∼97% fertile at the time of shedding. Germination of pollen on the stigma and the growth of pollen tubes have been traced in both naturally and manually (self- as well as cross-) pollinated pistils. The pollen:ovule ratio is ∼72:1 and the ovule: seed ratio is ∼2:1. Mature fruits are 8 or 9 ribbed and open by 2 or 3 longitudinal slits that release ∼32 seeds.     

Reproductive biology and pollination of southeastern Brazilian Stanhopea Frost ex Hook. (Orchidaceae)

Reproductive biology and pollination of Stanhopea lietzei and Stanhopea insignis were studied in a semi-deciduous mesophytic forest in the Serra do Japi (SJ), and in the coastal plain of Picinguaba, both in the State of São Paulo, Brazil. Floral morphology, pollination, breeding system and fruit set of both species were investigated. S. lietzei and S. insignis are pollinator-specific, being pollinated by male bees of Eufriesea (Apidae, Euglossini), which collect the fragrance produced by pluricellular osmophores at the base of the saccate hypochile. S. lietzei and S. insignis were pollinated by Eufriesea pulchra and Eufriesea purpurata, respectively. Observations using substances present in the floral fragrance of both studied species as chemical baits were also performed. E. purpurata was attracted by benzyl alcohol, the major compound of the perfume of S. insignis, while E. pulchra was attracted by none of the compounds used. Both studied Stanhopea are self-compatible but pollinator dependent. Self-pollination, however, tends to be avoided by floral mechanisms. In experimental self- and cross-pollinations the proportion of fruit abortion was high and related to resource limitation. The reproductive success of S. lietzei and S. insignis was low as a consequence of deficient pollen transference while pollinator scarcity was the main factor.     

First records of flower biology and pollination in African Annonaceae: Isolona, Piptostigma, Uvariodendron, Monodora and Uvariopsis

Seven species from five genera of Annonaceae were studied with regard to their flower biology and pollination in the Southwest Province of Cameroon, West Africa. They have protogynous hermaphroditic flowers, with exception of Uvariopsis species, which are monoecious. Fused petals of Isolona campanulata remain apically spreading and open during anthesis but form a deep basal urceolate tube around the reproductive organs. At anthesis the yellow pendent flowers emit a fruit-like scent and attracted small beetles, the likely pollinators. Piptostigma sp. flowers also emit a fruit-like scent but provide a closed pollination chamber formed by the three inner petals. Small staphylinid beetles attracted during the female stage of anthesis are released from the flowers at the end of the male stage 2-3 days later. Both species have diurnal anthesis, attracting and releasing the flower visitors during daytime. In contrast, Uvariodendron connivens and U. calophyllum have nocturnal anthesis with floral thermogenesis, produce spicy, aromatic and fruity scents and attract large Scarabaeidae beetles, the pollinators, along with many curculionid beetles, which were principally predators of the thick petals. The very large flowers of Monodora tenuifolia have yellowish petals which are spotted with dark red markings. Together with the sweetish, slightly disagreeable scent the flowers attract flies, principally dung flies. The two investigated Uvariopsis species are monoecious with pistillate and staminate flowers being functional at the same time. The violet red flowers of U. bakeriana visually seem to mimic the fruiting body of certain stinkhorn fungi (Phallaceae) although without producing their strong unpleasant carcass stench. Flower-visiting dung flies were rare. Conversely, U. congolana has a strong fungus-like scent, its flowers are presented at litter height and dung flies living in the litter were the flower visitors, albeit sporadic. The 4-5 days lasting anthesis of both Uvariopsis species appears to be an evolutionary consequence of their diffuse pollinator spectra. The studied African Annonaceae therefore have either cantharophilous or myiophilous/sapromyiophilous flowers with, in part, respectively, remarkably long anthesis, thermogenesis, and widely open, large flowers - all attributes unknown or rare in the hitherto better studied Neotropical Annonaceae.     

Life history and population biology of the giant ostracod Leuroleberis zealandica (Baird, 1850) (Myodocopida)

A population of this large myodocopid ostracod was studied over 2 yr by random core-sampling of the medium sand bottom at Kaikoura, New Zealand. Leuroleberis zealandica (Baird) passes through seven instars, it is sexually mature only in the final instar and sexes were distinguishable from instar IV. Males and females were equally abundant except in the final instar when the morphologically distinct males were rarely found. The population consists of three cohorts at any one time and each cohort appears to split into fast- and slow-growing individuals during the sixth instar resulting in life times of 1.8–2.0 and 2.7–3.1 yr, respectively. Females produce only one brood of 37 eggs on average per life time that are carried throughout the 5–6 month development period during which there is no loss of embryos. Recruitment is discrete with most broods released in midsummer when the population density may exceed 350·0.1 m^?2. A second lesser recruitment may occur in early spring in some years. Hatched juveniles released from the female grow rapidly to instar IV within 6 months and, although size increments at each moult are proportionally similar, intermoult periods tend to increase with size with some variation according to seasonal growth rates. Instar life tables constructed from instar density data showed a large difference in the frequency of embryos initiating each cohort, very different mortalities at recruitment between cohorts, and that the mortality rates between instars I and VI of different cohorts appear to be independent of density. The biology of Leuroleberis is compared with the few published accounts of myodocopid biology. In addition, several aspects of the biology of myodocopids are reviewed. These include numbers of instars in different taxa, within-instar sexual size disparities, numbers of broods per female life time, egg and brood sizes in relation to adult female size in various taxa, and the question of post-adult moulting.     

Comparative studies on the biology of nerita atramentosa Reeve, bembicium nanum (Lamarck) and cellana tramoserica (Sowerby) (gastropoda: Prosobranchia) in S.E. Australia

Populations of three coexisting intertidal gastropods, Nerita atramentosa Reeve, Bembicium nanum (Lamarck) and Cellana tramoserica (Sowerby), were sampled from a shore in Botany Bay, New South Wales, from July 1972 to September 1973. The recruitment and growth rates of each species were analysed from size frequency distributions. Mortality of each age cohort, and longevity, were estimated from analyses of the densities of Nerita atramentosa and Bembicium nanum.Nerita atramentosa showed no significant mortality during the first two years on the shore, but high mortality (at an instantaneous rate of 0.084 deaths/individual/month) after reaching the age of reproductive maturity, which was 20 months from settlement and at a mean shell-length of 13.5 mm. No growth could be detected after reproductive maturity was reached. Longevity of N. atramentosa was estimated as 3–5.5 years. Bembicium nanum juveniles showed higher mortality (at an instantaneous rate of 0.233 deaths/individual/month) than reproductively mature animals (0.060 deaths/individual/month). Reproductive maturity was reached at a mean shell-breadth of 11.0mm, i.e., about ten months after settlement on the shore. Longevity was estimated as from 4–8 years. Cellana tramoserica showed different growth patterns depending on the time of settlement.The three species showed different patterns of growth and life history relating to variable recruitment (which was demonstrated in all three species) and different rates of mortality of age cohorts.     

Ontogenetic systematics: The synthesis of taxonomy, phylogenetics, and evolutionary developmental biology

The main purpose of the present review is to draw attention to growing problems in the modern systematics and phylogenetics which are presently underestimated by the professional community. The dramatic reduction of the importance of ontogeny and morphology in phylogenetic studies of the second part of the 20th century is considered among the major factors of the modern taxonomic and evolutionary paradigm. The deep contradiction of modern approaches, which either merely consider systematics and phylogeny as genealogy or even in a neotypolgical manner irrespective of the evolutionary idea, is demonstrated. Thus, despite the widespread opinion that the evolutionary theory is the major basis for taxonomy, the processes, which in fact caused the origin and formation of the systematic hierarchy are often considered as redundant for the procedure of classification. In this respect, the classical, but well forgotten statement that evolution is a modification of ontogeny is specially highlighted. Tight relationships between evolution, ontogeny, systematics, and phylogenetics are prima facie obvious, but also presently underestimated, although the field of the evo-devo is continuously growing. Paradoxically, even despite the outburst of various molecular ontogenetic approaches, the commonly accepted evolutionary paradigm still lacks a general theory for changes in the shape of organisms. As a step towards the development of such a theory, a synthesis (or more exactly, resynthesis) of still largely independently developing major biological fields, i.e., ontogenetic and evolutionary studies, on the one hand, and traditional taxonomy, on the other hand, a new concept of ontogenetic systematics is proposed. The new concept is intended for integration of supposedly ??immobile?? traditional taxonomy with the dynamics, but predominantly considered as hypothetical, evolutionary field based on the process of ontogeny, which, in contrast to the evolution itself, can be observed in the real time. Therefore, it is concluded that, for instance, the evolution of the main group of living organisms Metazoa, is primarily the evolution of a very limited number of ontogenetic cycles that were formed as early as the Early Cambrian. A significant underestimation of cyclic properties of ontogeny in the evolution and systematics is shown. Using two model groups, echinoderms of the class Ophiuroidea and dorid nudibranch mollusks (Gastropoda: Doridacea), practical importance of the integrative approach developed here is demonstrated. The ??disruption?? of the ancestral ontogenetic cycle and further formation of a new descendant cycle (which implies some continuity of ancestral and descendant characters) is considered to be a major evolutionary pattern. The model proposed implies either progressive (addition of stages and characters) or regressive (reduction of already existing stages and structures) modification of ancestral taxon, the diagnosis of which corresponds to the model of its ontogenetic cycle. In the extreme cases of disruption of the ancestral ontogenetic cycle, adult characters of descendants are substituted by juvenile ancestral features, demonstrating paedomorphoses in the narrow sense. Within the framework of the approach proposed, the evolutionary and ontogenetic models of ancestral ontogenetic cycles of brittle stars and dorid nudibranchs are developed and discussed. Based on the original material of the extinct Paleozoic ophiuroid group Oegophiurida, the origin of key evolutionary novelties is discussed. A major conclusion of the present review is the high necessity of integration of new molecular data with already well-established taxonomic hierarchy and ontogenetic information as a basis for the development of the general theory of transformations of organisms, i.e., the theory of evolution in its true sense.     

Revision ofDoniophyton (Compositae, Barnadesioideae)

This revision describes, illustrates and documents morphological variation inDoniophyton (Compositae, Barnadesioideae), restricted to Argentina and Chile. Two species are recognized,D. anomalum andD. weddellii (sp. nova), possessing distinct morphological and chromosomal features, elevational tolerances, and nearly allopatric distributions.Doniophyton weddellii occurs primarily in central to northern Andean Chile and Argentina from 1900–4000 m a. s. l.;D. anomalum is found principally in centralwestern Argentina and south into Patagonia at 0–1800 m a. s. l. Close relationship exists withChuquiraga of subfam.Barnadesioideae. It is hypothesized thatDoniophyton evolved out ofChuquiraga in the high central Andes between Chile and Argentina. It is suggested thatD. weddellii differentiated first, correlating with an aneuploid chromosomal decrease from n = 27 (inChuquiraga) to n = 25. Further evolution and chromosomal decrease to n = 24 resulted inD. anomalum, with accompanying migration into southern Andes and Patagonia. Nomenclatural changes result from examination of protologues and type specimens:Doniophyton anomalum replaces the commonly used nameD. patagonicum, and a new species,D. weddellii, is described for the taxon masquerading under the routinely used superfluous nameD. andicola. This paper is dedicated with admiration and respect to emer. Univ.-Prof. DrFriedrich Ehrendorfer, one of the world's outstanding plant systematists, and a leading scientist and administrator of the Institute of Botany of the University of Vienna