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1.
Twelve species, six of which are new, are recorded from shores andshallow water. The most generally abundant are Spirorbis tricornigerus Rioja, S. bushi Rioja (both dextral with tube incubation), S. regalis sp. n., S. tuberculatus sp. n. (both sinistral with opercular incubation) and S. placophora sp. n. (sinistral, with tube incubation). Other sinistral species include S. claparedei Caullery & Mesnil, S. berkeleyana Rioja, S. bidentatus sp. n., and S. translucens sp. n. Dextral species include S. marioni Caullery & Mesnil, S. pagenstecheri Quatrefages and S. unicornis sp. n. The new species mentioned above have been described by the author named first.
The Spirorbis fauna seems to be quite like that of Mexico and S. America, from which repeated introductions have probably occurred, perhaps on stones buoyed by seaweeds and drifting on the Peruvian and El Nino currents. Its considerable diversity is not attributed to speciation within the archipelago.  相似文献   

2.
Twelve species are described, of which two are new, viz. Spirorbis (Janua) gnomonicus and Spirorbis (J.) parvulus, and three others have been recognized only very recently, viz. S. (Pileolaria) clavus, S. (P.) endoumensis, S. (P.) heteropoma. Some such as 5. (jf.) corrugatus and S. (P.) koehleri were widely distributed between depths of 0–60 m, but others showed a tendency towards depth zonation, with S.(J.)pagenstecheri abundant in shallow and S. (Spirorbis) cuneatus in somewhat less shallow water. 5. (P.) pseudomilitaris and S. (Marsipospira) striatus were confined to greater depths except where the former occurred amongst ships fouling and the latter in a dark cave. 5. (P.) militaris seems rather uncommon.
A remarkably high percentage of the species (over 80%) are opercular incubators. Outside the Mediterranean, the only areas known to have similar percentages are Ceylon and the West Indies, suggesting that the habit may have originated in the Sea of Tethys.  相似文献   

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4.
This genus resembles most other tube-incubating Spirorbinae of the Southern Hemisphere in having a very asymmetrical distribution of uncini. It is particularly close to Protolaeospira , having a thoracic stalk for the attachment of embryos, and may have evolved recently from this genus, by simplification of collar setae. The straightened tube may be an ecophenotypic response to life on muddy bottoms.  相似文献   

5.
A new genus, a new subgenus, four new species and four previously described species are recorded from the Red Sea. The new genus Anomalorbis has four and a half thoracic segments. Re-discovery of the sinistral variety of Janua (Dexiospira) steueri confirms Sterzinger's observation that this species may coil in either direction. Janua (Fauveldora) anticorrugata sp. nov. is also sinistral and a shallow water species. It therefore appears that the Red Sea may have been the centre of origin for sinistral mutants of the Janua complex. Other of the new forms live in fairly deep water. The assemblage encountered shows closest affinity with the Indo-Pacific, but suggests a high degree of endemism, which may be related to the high temperatures prevailing at all depths in the Red Sea.  相似文献   

6.
Of four species studied, tolerance of extreme temperatures in greatest in Spirorbis pagenstecheri (which extends highest on the shore) and least in S. corallinae (which always occurs immersed in water). The latter species breeds between May and August, the other three from May to October. S. borealis liberates its larvae mainly at the moon's quarters, but this fortnightly rhythm is less obvious in S. corallinae and not found in the other two species. S. corallinae differs from S. borealis in being slower to re-emerge after disturbance and in having a lesser breeding size, maximum size and life span. Growth in the laboratory is slower in S. tridentatus than in the other species. Growth of S. borealis under natural conditions is much faster in summer than in winter.  相似文献   

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8.
重订羌活属的分类   总被引:14,自引:0,他引:14  
在野外实地观察和标本整理的基础上,检查了羌活属各个分类群的分类问题,考证了它们的名称。通过性状分析,主要以小总苞片的形状及其相关特征作为属下分类的依据,将卵叶羌活N.oviforme 改隶于宽叶羌活之下作为亚种处理,支持张盍曾在1975年将 N.franchetii 与N.forbesii合并为1种。如此,该属共5种,其中1种含1亚种。描述了两个新组,对属的特征和地理分布作了补充。近年该属新增加2种,因此分种检索表也作了相应的修改。  相似文献   

9.
Janua (Dexiospira) brasiliensis and J. (D.) foraminosa are fully described for the first time and compared by a pictorial key with other species of Dexiospira and Pillaiospira . The former is very close to J. (D.) pseudocorrugata (= "Sptrorbis corrugatus" ) and particularly to J. (D.) nipponica , whilst the latter occupies a central position in the group of five species (including J. (D.) steueri ) which are characterized by having large four-lobed juvenile talons.
Janua (Janua) pagenstecheri is the most widespread species of the genus, whereas J. (Leodora) knightjonesi seems to be confined to coral seas. In all, 14 species of Janua are recognized, whilst 19 names are here regarded as synonyms or varieties. Eleven other species sometimes placed in Dexiospira or Leodora should rather constitute the genera Circeis, Sinistrella and Romanchella . These are re-defined and their affinities are studied.
The subgenus Dexiospira seems to be centred in the Indo-West Pacific, where it reaches maximum species-diversity and extension into cooler latitudes. J. (D.) pseudocorrugata var. mannarensis is pantropical and overlaps in the Mediterranean with the west European form and in the West Pacific with vars praeceps and fenestrata , and with subspecies ainu , which are characterized by small modifications of the tube or abdominal setae.  相似文献   

10.
The genus Notopterygium is endemic to China. The plants of this genus are important traditional Chinese medicine. When established by H. de Boissieu in 1903, Notopterygium included only two species, i.e.N. franchetii and N. forbesii. Within nearly a century, five more specific names had been added to this genus, i.e.N. forrestii H. Wolff, N. oviforme Shan, N. incisum Ting ex H. T. Chang, N. pinnatiinvolucellatum Pu et Y. P. Wang, N. tenuifolium Sheh et Pu. Based on field ervation and examination of herbarium specimens, all the taxa in this genus were taxonomically reviewed and their nomenclature was carefully checked. N. oviforme was treated as a subspecies under N. forbesii. We agree with Chang He-Tseng in reducing N. franchetii to N.forbesii as a synonym. As a result, five species, one of which contains a subspecies, are recognized. Based on the morphology of involucel bractlets as well as their relevant characters, Notopterygium is divided into two sections.Sect. 1. Notopterygium Basal and proximal cauline leaves 2-ternate to 2 ~3-ternate-pinnate, ultimate divisions broadovate or ovate-lanceolate; involucel bractlets linear, entire, vascular bundles of petiole approximately equal in size. This section contains two species and one subspecies.Sect. 2. Tenuifolium Pu, sect. nov.Basal and proximal cauline leaves 2 ~3-ternate-pinnate, ultimate divisions ranceolate,ovate-lanceolate or linear; involucel bractlets linear, entire or oblanceolate, 2 ∽ 3-fid or pinnate at the apex; vascular bundles of petiole unequal in size. This section centains three species.  相似文献   

11.
J. M. Gee 《Journal of Zoology》1967,152(2):235-244
Settlement of young occurred mostly between June and September. Monthly increments in coil diameter of tubes were about 0.5 to 0.7 mm between September and January, but only about 0.2 mm between January and March. Growth seems to continue throughout life, which lasts for about a year. Breeding may begin at a coil diameter of about 2 mm, but is more prolific in larger individuals. Maturation of gametes occurred slowly at 5C, more rapidly at higher temperatures. Spawning occurs between March and October, particularly between April and September. Incubation lasts for much more than a fortnight and there was no trace of the neap tide breeding rhythm seen in closely related species.  相似文献   

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14.
The planktonic filter feeder Daphnia magna depends on a steady oxygen supply by convection. In the ventral carapace chamber, this convection is established by the feeding current which is generated by the movement of the thoracic limbs. The present study revealed that this movement can cause an additional flow of medium which passes through the brood chamber of the animal. To visualise this current, ink or fluorescent microspheres were released by a microcapillary near the posterior opening of the brood chamber. The tracks of these probes were monitored by video microscopy. Digital motion analysis was used for the determination of flow velocity and flow rate. Ambient medium entered the brood chamber at the abdomen of the animal and moved then to the anterior end of the brood chamber before entering the ventral carapace chamber. Two horizontal lamellae, which are attached at both sides of the trunk and project laterally to contact the carapace walls, almost completely separate the dorsal brood chamber from the ventral carapace chamber. Water can only pass these barriers through small depressions in these lamellae at the level of the 3rd and 4th appendages. Female daphnids with embryos at late developmental stages showed more rapid water currents in the brood chamber than those with younger embryos. Moreover, animals showed higher flow rates when exposed to hypoxic conditions. As the oxygen uptake rate of older embryos is approximately three times higher than that of younger embryos, the enhanced brood chamber current could improve the oxygen availability for both the mother and its brood under conditions of reduced oxygen availability.  相似文献   

15.
In this paper we report the up to now ignored fluorescence properties of the specific Cu(I)-chelator bathocuproine disulfonate and their application in assays of total copper and Cu(I). The method is based on the linear quenching of the bathocuproine disulfonate emission at 770 nm (lambda(ex)580 nm) by increasing concentrations of Cu(I), at pH 7.5. Copper concentrations as low as 0.1 microM can be determined. Other metal ions (iron, manganese, zinc, cadmium, cobalt, nickel) do not interfere. The procedure for total copper determination in proteins includes HCl treatment to release the copper, neutralization to pH 7.5 in the presence of citrate to stabilize the copper, and reduction of the copper to Cu(I) by ascorbate in the presence of the chelator. This assay gave results coincident with the analysis by atomic absorption spectroscopy in two selected proteins. In addition, conditions are described (omitting HCl treatment and reduction by ascorbate) for direct measurement of Cu(I) in native proteins, as illustrated for the Escherichia coli NADH dehydrogenase-2. Data show that the fluorometric assays described in this paper are simple and convenient procedures for total copper and direct Cu(I) quantification in determined biological samples.  相似文献   

16.
Incubation in most avian species involves transferring heat from parent to egg through a highly vascularized brood patch. Some birds, however, do not develop a brood patch. Unusual among birds, these species hold their eggs under the webs of their feet, but the role of the feet in heat transfer is uncertain. Often the webs are positioned between the feathered abdomen and the egg during incubation, suggesting that either the abdomen, the feet, or both could transfer heat to the egg. We studied heat transfer from foot webs to eggs during incubation in Nazca boobies by spatially separating the feet from the abdomen using an oversized egg. We found that feet transfer heat to eggs independently of any heat that may be transferred from the abdomen. In addition, we found that incubating boobies had significantly greater vascularization in their foot webs, measured as a percentage of web area covered by vessels, than nonincubating boobies. We also found that males, whether incubating or nonincubating, had significantly less web vascularization than females. We concluded that vascularized Nazca booby feet function in the same way during incubation that vascularized brood patches do, acting as surrogate brood patches.  相似文献   

17.
From the study of more than 450 specimens of Hydroides and Serpula, 12 species from the Grand Caribbean Region were identified and characterized. Eight species were collected along the shores of the Yucatan Peninsula and five were found in other localities in the Gulf of Mexico, seven others are from Cuba and comments on type specimens of five species are also included. One morphometric analysis made on Hydroides mucronatus Rioja and Hydroides cf. mucronatus, indicated several differences among them. Comments on all species are also included.  相似文献   

18.
A new “reef ” of the serpulid polychaete Serpula narconensis Baird, 1885 is reported from the South Georgia Island shelf. This particular mass occurrence is the second serpulid “reef” reported in the Antarctic region. Its location, at 91- to 105-m depth, is very different from those serpulid reefs previously reported, usually sited at intertidal zone or at low depth, and this may be one of the largest, if not the largest, serpulid reef in the world. Accepted: 12 June 1999  相似文献   

19.
Chemosensory proteins (CSPs) are ubiquitous soluble small proteins isolated from sensory organs of a wide range of insect species, which are believed to be involved in chemical communication. We report the cloning of a honeybee CSP gene called ASP3c, as well as the structural and functional characterization of the encoded protein. The protein was heterologously secreted by the yeast Pichia pastoris using the native signal peptide. ASP3c disulfide bonds were assigned after trypsinolysis followed by chromatography and mass spectrometry combined with microsequencing. The pairing (Cys(I)-Cys(II), Cys(III)-Cys(IV)) was found to be identical to that of Schistocerca gregaria CSPs, suggesting that this pattern occurs commonly throughout the insect CSPs. CD measurements revealed that ASP3c mainly consists of alpha-helices, like other insect CSPs. Gel filtration analysis showed that ASP3c is monomeric at neutral pH. Using ASA, a fluorescent fatty acid anthroyloxy analogue as a probe, ASP3c was shown to bind specifically to large fatty acids and ester derivatives, which are brood pheromone components, in the micromolar range. It was unable to bind tested general odorants and other tested pheromones (sexual and nonsexual). This is the first report on a natural pheromonal ligand bound by a recombinant CSP with a measured affinity constant.  相似文献   

20.
刘燕媚  汪安泰  李世昌  李荔 《四川动物》2012,31(3):393-396,332
对分布于中国深圳的宋卡湖根管虫Ficopomatus talehsapensis Pillai,2008进行了实验观察.结果表明:1)雌雄异体,精子或卵从鳃冠基部喷射至水中,体外受精,繁殖力强,受精后约0.8h开始卵裂,生活史经历早期胚胎发育、担轮幼虫、后担轮幼虫、游毛幼虫、后游毛幼虫、刚节幼体及成虫;2)鳃丝具呼吸、感觉、滤食功能,以单细胞藻类和有机碎屑为食;3)担轮幼虫至成体均具眼点,但视觉功能退化;4)对水环境的适应能力极强.讨论了根管虫对生境水质的影响.  相似文献   

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