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The Australian wolf spider genus Hoggicosa Roewer, 1960 with the type species Hoggicosa errans (Hogg, 1905) is revised to include ten species: Hoggicosa alfi sp. nov. ; Hoggicosa castanea (Hogg, 1905) comb. nov. (= Lycosa errans Hogg, 1905 syn. nov. ; = Lycosa perinflata Pulleine, 1922 syn. nov. ; = Lycosa skeeti Pulleine, 1922 syn. nov. ); Hoggicosa bicolor (McKay, 1973) comb. nov. ; Hoggicosa brennani sp. nov. ; Hoggicosa duracki (McKay, 1975) comb. nov. ; Hoggicosa forresti (McKay, 1973) comb. nov. ; Hoggicosa natashae sp. nov. ; Hoggicosa snelli (McKay, 1975) comb. nov. ; Hoggicosa storri (McKay, 1973) comb. nov. ; and Hoggicosa wolodymyri sp. nov. The Namibian Hoggicosa exigua Roewer, 1960 is transferred to Hogna, Hogna exigua (Roewer, 1960) comb. nov. A phylogenetic analysis including nine Hoggicosa species, 11 lycosine species from Australia and four from overseas, with Arctosa cinerea Fabricius, 1777 as outgroup, supported the monophyly of Hoggicosa, with a larger distance between the epigynum anterior pockets compared to the width of the posterior transverse part. The analysis found that an unusual sexual dimorphism for wolf spiders (females more colourful than males), evident in four species of Hoggicosa, has evolved multiple times. Hoggicosa are burrowing lycosids, several constructing doors from sand or debris, and are predominantly found in semi‐arid to arid regions of Australia. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 83–123. 相似文献
164.
Jian Cheng 《Steroids》2010,75(11):754-759
Biologic sex and sex steroids are important factors in clinical and experimental stroke. This review evaluates key evidence that biological sex strongly alters mechanisms and outcomes from cerebral ischemia. The role of androgens in male stroke is understudied and important to pursue given that male sex is a well known risk factor for human stroke. To date, male sex steroids remain largely evaluated at the bench rather than the bedside. We review recent advances in our understanding of androgens in the context of ischemic cell death and neuroprotection. We also highlight some possible molecular mechanisms by which androgens impact ischemic outcomes. 相似文献
165.
J. C. DEEMING 《Zoological Journal of the Linnean Society》1981,71(2):159-169
Enigmilkhia dimorphka gen. et sp. nov. and Milkhia distinctipennis, fumicoslata, savannaticola and sylvicola spp. nov. are described from tropical Africa. These forms, though belonging to different subfamilies, exhibit a very similar sexual dimorphism in the shape and chaetotaxy of the frons. Such a dimorphism is unknown within the Milichioidea. 相似文献
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John Prenter Robert W. Elwood W. Ian Montgomery 《Evolution; international journal of organic evolution》1999,53(6):1987-1994
We investigate the association between female reproductive investment, absolute size, and sexual size dimorphism in spiders to test the predictions of the fecundity-advantage hypothesis. The relationships between absolute size and sexual size dimorphism and aspects of female reproductive output are examined in comparative analyses using phylogenetically independent contrasts. We provide support for the idea that allometry for sexual dimorphism is the result of variation in female size more so than male size. Regression analyses suggest selection for increased fecundity in females. We argue that fecundity selection provides the only general explanation for the evolution of sexual size dimorphism in spiders. 相似文献
169.
MICHAEL A. SCHILLACI LISA JONES-ENGEL BENJAMIN P. Y.-H. LEE AGUSTIN FUENTES NANTIYA AGGIMARANGSEE GREGORY A. ENGEL TULYAWAT SUTTHIPAT 《Biological journal of the Linnean Society. Linnean Society of London》2007,92(4):675-694
Crab-eating, or long-tailed, macaques [ Macaca fascicularis (Raffles, 1821)] have been studied extensively throughout their distribution in South and South-east Asia. Despite this extensive body of research, the island population of long-tailed macaques from Singapore remains virtually undescribed. In the present study, we compare the morphometric variability and patterns of growth observed in a population sample from Singapore with a composite sample from Thailand, north of the Isthmus of Kra. The results of our analyses indicate that there are statistically significant differences between the two populations in adult size and shape. For both males and females, the Singapore population is smaller than the Thai population. Relative to body length, the Singapore macaques exhibit significantly longer tails, and, relative to cranial length, they exhibit significantly more narrow faces than the Thai macaques. Although levels of sexual dimorphism for most morphometric traits are very similar, indicating similar levels of male–male competition for females, the Singapore males exhibit a significantly larger testicular volume relative to body weight, suggestive of an alternative male reproductive strategy. In addition to adult somatometric size and shape, comparisons of growth patterns relative to age and body size reveal significant differences between the two population samples. Combined, these results suggest either that statistically significant differences in adult morphology and patterns of growth can occur in presumably reproductively cohesive subspecies, or the Singapore macaques may be taxonomically distinct. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 92 , 675–694. 相似文献
170.
Members of the species Mucor ramannianus are believed to be monomorphic. They grow only as a mycelium and are not capable of growth as budding cells, i.e., of dimorphic growth. In our study, we investigated the lipid composition of M. ramannianus sporangiospores, which retained the capability of initiating mycelial growth in the course of long-term cultivation of the spore-forming mycelium. It was demonstrated that sporangiospores contained high concentrations of triacylglycerides (TAG) in their reserve lipids and high concentrations of phosphatidylcholine (PC) in their membrane lipids; low concentrations of methylated ergosterol precursors were detected among sterols. On the basis of the data presented, in order to evaluate the potential of mucor fungi for yeastlike growth, it has been suggested to analyze the qualitative and quantitative characteristics of their sporangiospore lipids and to consider the following criteria as the criteria of sporangiospore capacity for giving rise to yeastlike growth upon spore germination: (1) the phosphatidylethanolamine/phosphatidylcholine (PE/PC) ratio; (2) the level of ergosterol and the ratio between the methylated and demethylated sterols; as well as (3) the ratios between phospholipids and glycolipids (PL/GL) and (4) between etherified and free sterols (ES/FS). 相似文献