The genera Lithothamnium,Leptophytum (nov. gen.) and Phymatolithon in the Gulf of Maine

Summary This paper is the fourth of a series covering the crustose corallines of the Gulf of Maine. Information on anatomy, cytology and the development of the reproductive structures is presented to show that Lithothamnium and Leptophytum (new genus) are distinct from Clathromorphum and Phymatolithon. An additional species, P. lenormandi, is placed in Phymatolithon. The reproductive patterns and geographic and bathymetric distributions of the five species involved are presented and discussed.The necessary field work for this study was made possible by the generous support of: The American Petroleum Institute, The Geological Society of America and the ONR (through the Department of Geology and Geophysics, Massachusetts Institute of Technology).     

The genus phymatolithon in the Gulf of Maine

Summary New information on anatomy, cytology and the development of reproductive structures is presented to show that Phymatolithon is a genus distinct from both Clathromorphum and the branching members of Lithothamnium. Also, a new species of Phymatolithon, Ph. rugulosum, is described. The reproductive cycles and geographic and bathymetric distributions of Ph. laevigatum and Ph. rugulosum in the Gulf of Maine are presented and discussed. There is strong indication that the geographic distribution of crustose corallines in the region is controlled primarily by maximum summer temperatures. The depth distributions are apparently controlled primarily by decrease of light with depth, though temperatures and substrate are also factors.Now at Colorado School of Mines, Golden, Colorado, U.S.A. The necessary field work for this study was made possible through the generous support of: The American Petroleum Institute, The Geological Society of America, the ONR (through the Department of Geology and Geophysics, Massachusetts Institute of Technology) and the Woods Hole Oceanographie Institution (Contr. No. 1500).     

The genus Pseudolithophyllum (Corallinaceae) in the Gulf of Maine

Summary This is the third of a series of papers covering the anatomy, morphology, systematics and ecology of the crustose corallines of the Gulf of Maine. Pseudolithophyllum orbiculatum, the only species of this genus in the region, is treated in this paper.Part of a study undertaken while working on a Ph. D. program at the University of Michigan. The necessary field work was made possible by the generous support of: the American Petroleum Institute (Grant-in-aid No. 85), the Geological Society of America (Penrose Grant No. 912-62), the Office of Naval Research (Nonr 1841-74), through the Department of Geology and Geophysics, Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution.     

UNDERWATER CROSS-POLLINATION IN CALLITRICHE HERMAPHRODITICA (CALLITRICHACEAE): EVIDENCE FROM RANDOM AMPLIFIED POLYMORPHIC DNA MARKERS

Underwater cross pollination (hypohydrophily) represents a markedly divergent form of pollination in seed plants; reproductive structures are functionally wet during pollination. Callitriche (Callitrichaceae) is the only genus in which both aerial pollination systems and hypohydrophily are reported. This diversity in pollination types would not be predicted based on the general uniformity in floral structure in the genus. Logistic difficulties in conducting experimental pollination studies in C. hermaphroditica have plagued actual confirmation of hypohydrophily. Evidence from paternity exclusion analysis using random amplified polymorphic DNA markers is presented that confirms hypohydrophily in C. hermaphroditica.     

Reproductive mode evolution in nematodes: insights from molecular phylogenies and recently discovered species

The Phylum Nematoda has long been known to contain a great diversity of species that vary in reproductive mode, though our understanding of the evolutionary origins, causes and consequences of nematode reproductive mode change have only recently started to mature. Here we bring together and analyze recent progress on reproductive mode evolution throughout the phylum, resulting from the application of molecular phylogenetic approaches and newly discovered nematode species. Reproductive mode variation is reviewed in multiple free-living, animal-parasitic and plant-parasitic nematode groups. Discussion ranges from the model nematode Caenorhabditis elegans and its close relatives, to the plant-parasitic nematodes of the Meloidogyne genus where there is extreme variation in reproductive mode between and even within species, to the vertebrate-parasitic genus Strongyloides and related genera where reproductive mode varies across generations (heterogony). Multiple evolutionary transitions from dioecous (obligately outcrossing) to hermaphroditism and parthenogenesis in the phylum are discussed, along with one case of an evolutionary transition from hermaphroditism to doioecy in the Oscheius genus. We consider the roles of underlying genetic mechanisms in promoting reproductive plasticity in this phylum, as well as the potential evolutionary forces promoting transitions in reproductive mode.     

Reproductive Asynchrony and the Divergence of Hawaiian Crickets

Asynchrony in reproductive behavior may contribute to reproductive isolation among sympatric species. While the 38 cryptic species of the genus Laupala are primarily distinguished on the basis of variation in pulse rate of male calling songs, additional phenotypes, such as asynchrony in reproductive behavior, may contribute to reproductive isolation in this genus. Here we document similarities and differences in the diel timing of two reproductive behaviors, male singing activity and insemination events. Asynchrony in the diel timing of male singing behavior was observed between two sympatric species, Laupala cerasina and Laupala paranigra, in the field. An interpopulational comparison within L. cerasina did not reveal variation in diel behavior patterns of singing between two locations. Asynchrony in the timing of copulation and sperm transfer between L. cerasina and L. paranigra was documented in the laboratory. The observed pattern of asynchrony in both the field and laboratory could have arisen in a number of ways. One possibility is that species diverged in sympatry because of interspecific interactions, producing a pattern of reproductive character displacement. Alternatively, the observed asynchrony in reproductive behavior may have played a role in the process of community assembly within this recently diverged cricket genus. The presence of interspecific variation and the absence of intraspecific variation revealed by our study do not support a pattern of reproductive character displacement for diel reproductive behavior, suggesting that the differences seen between species were not caused by recent species interactions.     

Neotapirissus gen. nov. of the tribe Issini (Hemiptera: Fulgoromorpha: Issidae) from Hainan Island

Neotapirissus gen. nov. , in the tribe Issini (Hemiptera: Fulgoromorpha: Issidae), is described from China, and type species Neotapirissus reticularis sp. nov. (China: Hainan) is described and illustrated. The female internal reproductive organs of the new species are also described and illustrated. The new genus is compared to the superficially similar genus Tapirissus Gnezdilov. The morphological diversity of the issids distributed in Hainan Island is discussed briefly.     

A STUDY ON GENUS INDOMEGOURA (HOMOPTERA: APHIDIDAE) AND NOTES ON NEW SPECIES*

Abstract The genus Indomegoura Hille Ris Lambers, 1958 was inveatigated in this paper. One new species I. crassirostra Qiao and Zhang was described. Based on the study of all four known species (including the new species above), a key to species was given. According to the geographical distribution of the genus and phytogeographical of host plants, the recent differentiation center of this genus could be located in Center China sub-region, Oriental Realm. All the specimens examined are deposited in Institute of Zoology, Academia Sinica.     

Morphology, reproductive biology and molecular genetics of ovoviviparous freshwater gastropods (Cerithioidea, Pachychilidae) from the Philippines, with description of a new genus Jagora

The new genus Jagora of the family Pachychilidae Troschel, 1857 is described for the type species Melania asperata Lamarck, 1822 from the Philippines. In addition to J. asperata, a second endemic species of the new genus, J. dactylus (I. Lea & H.C. Lea, 1850), is recognized on the basis of shell morphometry and molecular genetic data (cytochrome C oxidase I and 16S rRNA). The taxonomic history of J. asperata and J. dactylus is revised and the recent distribution documented on basis of available museum material and the authors’ own field collections. J. asperata occurs on Luzon and its satellite islands Leyte and Samar, while J. dactylus is restricted to the Visayan islands Bohol, Cebu, and Guimeras. The morphology of the two species is presented and illustrated in detail, and compared to taxa of the closely related genus Brotia H. Adams, 1866 to which they were previously assigned. Among the South‐east Asian freshwater Cerithioidea of the family Pachychilidae, which were previously subsumed under Brotia for their more or less similar shell morphology and operculum, three distinct lineages can be distinguished, in particular by means of distinct reproductive anatomy: (1) the species of Brotia sensu stricto from mainland South‐east Asia, Sumatra, Borneo and Java, which all exhibit a subhaemocoelic brood pouch; (2) the pachychilid species endemic to Sulawesi, currently assigned to the genera Brotia and Tylomelania, as well as both species of Pseudopotamis endemic to the Torres Strait Islands, which possess a uterine brood pouch; (3) the females of the Philippine Jagora, which carry egg capsules, embryos and advanced juvenile stages within the mantle cavity — a unique reproductive feature. Associated with this mode of ovoviviparity, Jagora is characterized by additional unique properties of the reproductive system including a deeply incised and long sperm gutter in the medial lamina, a very short and posteriorly positioned spermatophore bursa formed by the medial lamina, and a prominent lateral ridge functioning as a seminal receptacle. These characteristics are exclusive to Jagora and are consequently considered to represent autapomorphies of this clade which is endemic only to the Philippines. The zoogeographical implications are discussed in connection with a recently developed palaeogeographical reconstruction.     

Multiple reproductive strategies of a spring ephemeral plant,Fritillaria maximowiczii,enable its adaptation to harsh environments

Spring ephemeral plants that experience harsh environments have developed specific reproductive characteristics. These characteristics are of great importance to the survival and reproduction of these species, particularly for rare and endangered plants. Fritillaria is a genus consisting of spring ephemeral plants with significant medicinal and ornamental value whose wild resources are highly threatened and whose reproductive characteristics and adaptative evolutionary mechanisms are still not well understood. Fritillaria maximowiczii is positioned at the most basal clade on the Fritillaria phylogenetic tree, whose reproductive characteristics remain obscure. In this study, we report the flowering dynamics, pollination biology and breeding system of F. maximowiczii. The flowering process of F. maximowiczii can be divided into seven stages. Based on the pollen/ovule ratio, the outcrossing index and a field pollination experiment on a natural population, F. maximowiczii showed high levels of outcrossing and self-compatibility. Three types of pollinators were observed: two kinds of bumblebees, and spiders. Diverse herkogamy and dichogamy may have considerably improved its reproductive success rate. Furthermore, a special reproductive mode not previously reported in wild populations of Fritillaria, apomixis, was strongly suspected based on a high fruit setting rate (36.84%). Our study suggests F. maximowiczii has developed multiple reproductive strategies to adapt to harsh environments and ensure population reproduction, and the diverse reproductive mechanisms may be related to its primitive phylogenetic position in the genus. This study not only broadens our understanding of mechanisms of ecological adaptation in spring ephemeral plants but also provides key data for the conservation of Fritillaria.     

Segregation distorter in D. melanogaster males: An effect of female genotype on recovery

Summary Segregation Distorter (SD) is a gene affecting sperm recovery in Drosophila melanogaster. In a cross SD/SD ⁺ x SD⁺, the proportion of SD/SD ⁺ zygotes recovered (k) is larger than the 0.50 expected. Previous investigations have shown that the relative recovery of SD- and SD ⁺-bearing sperm is determined at or before the meiotic divisions. Evidence is presented here that k is influenced by the genotype of the female parent. It is suggested that the SD gene product causes a difference in the enzymatic or structural complement of the SD- and SD ⁺-bearing sperm which largely determines their relative functionality. The effect of the female genotype on recovery is interpreted as an interaction between this physiological difference and the environment of the female reproductive tract.Adapted from a dissertation presented by the senior author in partial fulfillment of the degree of Doctor of Philosophy. This investigation was supported by PHS Training Grant No. GM 00337 and PHS Research Grant No. GM 12334 from the National Institute of General Medical Sciences.     

The reproductive biology of two poorly known relatives of the fig (Ficus) and insights into the evolution of the fig syconium

We conducted the first detailed investigation of the floral architecture and reproductive biology of two species from the genus Dorstenia, which are poorly known relatives of Ficus (Moraceae). Our aims were to extend and refine knowledge of the understudied genus Dorstenia and to explore possible insights into the evolution of the fig syconium. We characterised four key stages of floral development using light microscopy, scanning electron microscopy and histological staining. Reproductive biology was found to be complex and species‐specific. Both study species are monoecious and produce an inflorescence of minute male and female flowers. Protogyny, associated with a spatial separation of male and female flowers and asynchronous stamen development, was species‐specific, as was seed set. Our results reveal novel insights into the complex reproductive biology of an under‐studied genus in the family Moraceae. We propose that exploring the reproductive biology of Dorstenia and other poorly known Ficus relatives will provide insights into the evolution of the fig syconium – the unique reproductive structure of this economically and ecologically important genus.     

Social and life history correlates of litter size in captive colonies of precocial spiny mice (<Emphasis Type="Italic">Acomys</Emphasis>)

Litter size is an important component of life history contributing to reproductive success in many animals. Among muroid rodents, spiny mice of the genus Acomys are exceptional because they produce large precocial offspring after a long gestation. We analyzed data on 1,809 litters from laboratory colonies of spiny mice from the cahirinus-dimidiatus group: Acomys cahirinus, Acomys cilicicus, Acomys sp. (Iran), and Acomys dimidiatus. Generalized mixed-effect models revealed that litter size increased with maternal body weight and/or number of immature females present in the family group. Thus, both maternal body reserves and presence of immature descendants demonstrating previous reproductive success enhance further reproduction in this social rodent.     

Systematic study of the genus Cyphononyx (Hymenoptera: Pompilidae) occurring in Japan

Generic characteristics and phylogenetic relationships of the genus Cyphononyx are presented, together with a brief review of the biology of the genus. It is shown that only one species of the genus, C. fulvognathus (Rohwer), occurs in Japan. This species is distributed also in Taiwan and south China, and has hitherto been recognized under the name of C. dorsalis. In addition, two new combinations are presented: Cyphononyx hirtus (Haupt, 1935) (= Cryptochilus hirtus Haupt) and Cyphononyx plebejus (de Saussure, 1867) (= Agenia plebeja de Saussure), both of which were recorded from the Oriental Region.     

Length‐weight relationships of four snowtrout species from the Kashmir Valley in India

Length–weight relationships (LWR) are presented for one species of the genus Schizopyge [S. curvifrons (Heckel, 1838)] and three species of the genus Schizothorax [S. esocinus (Heckel, 1838), S. labiatus (McClelland, 1842) and S. plagiostomus (Heckel, 1838)] from different water bodies of the Kashmir Valley, India. A total of 774 specimens were sampled and measured from January to November 2011. No information regarding LWRs of these species was available in FishBase.     

On Nanognathia,a New Gnathostomulid Genus from the East Coast of the United States

In continuation of a series of papers describing new representatives of the phylum Gnathostomulida from the east coast of North America, the monotypic genus Nanognathia is presented. It is distinguished by small size, grouped epidermal inclusions on the ventral body surface, and flattened basket-type jaws with long teeth of which one is developed as a terminal tooth. Together with the structure of the reproductive system, these characteristics place Nanognathia within the suborder Scleroperalia, family Onychognathiidae.     

A study of the red alga,Calonitophyllum medium (Hoyt) comb. Nov. [= Hymenena media (Hoyt) Taylor]

Ontogeny of the vegetative system and reproductive structures found in Hymenena media (Hoyt) Taylor (Delesseriaceae, Nitophylleae) indicates that the alga is similar to the Phycodrys group in its vegetative development, and to the Nitophyllum group in its female reproductive system. The vegetative system bears striking resemblance to the type species of a European genus, Radicilingua [R. thysanorhizans (Holm.) Papenf.]. Reproductive structures of two other species of this genus, R. adriatica (Kylin) Papenf. and R. reptans (Zanard.) Papenf. and the type species are inadequately known. On the basis of several vegetative characters and the location and superficial organisation of the tetrasporangial sori, a new genus, Calonitophyllum, is proposed to contain our Western Atlantic plants. The new combination, Calonitophyllum medium (Hoyt) Aregood, thus replaces Hymenena media (Hoyt) Taylor.