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The zoeal stages of Hiplyra variegata are described and illustrated for the first time. Zoea I was obtained from an ovigerous female, and the zoea II and zoea III stages were captured in the plankton (their identity was confirmed by rearing some of them from earlier stages). Comparisons are made with the only other species of the genus of which larvae are known, i.e. H. platycheir. The presence of a lateral spine on the carapace of zoea I is one of the most important characters that can be used for easy recognition of H. variegata. It is important to note that the third zoea of H. variegata has four small spines at each posterolateral margin of the carapace, in contrast to three spines in other species.  相似文献   

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《Journal of Natural History》2012,46(31-32):2079-2093
The population characteristics of four deep‐water pandalid shrimps (Decapoda: Caridea) were studied in the northern Aegean Sea in samples collected annually (1997–2000) in summer, through experimental trawl, at depths down to 600 m. Females were larger than males in Plesionika martia and Plesionika heterocarpus; no significant differences in size of males and females were found in Chlorotocus crassicornis and Plesionika antigai. A trend of increasing size with depth was observed, as well as a linear increase in the proportion of females with increasing size. Sex ratio was skewed towards females at all depths in P. antigai, while in P. heterocarpus and C. crassicornis males dominated the intermediate depths. Negative allometries were apparent in the carapace length–weight relationships in males of all species. Isometric relationships were found in females apart from in P. heterocarpus. The population patterns conform to relevant Mediterranean reports. However, some population differences exist that may reflect the distinct environmental conditions prevailing in the study area.  相似文献   

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《Journal of Natural History》2012,46(29-32):1875-1927
Nine species of the family Phacopteronidae are recorded from Cameroon. All are assigned to the large pan‐tropical genus Pseudophacopteron. Eight species are described as new, and P. electum Capener is redescribed. The species are diagnosed and illustrated, and keys for the identification of adults and fifth instar larvae are provided. Information is given on distribution, host plants, and biology. Eight species are associated with plants of the order Rutales/Sapindales (three Sapindaceae, one Burseraceae, one Burseraceae or Anacardiaceae, one Meliaceae, one Rutaceae, and one Anacardiaceae/Simaroubaceae); host plants of one species remain unknown. Four species, namely P. electum, P. fuscivenosum sp. n., P. lecaniodisci sp. n., and P. morion sp. n., induce nut or pit galls on the leaves.  相似文献   

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The bopyrid parasite Orbione halipori was recorded for the first time from Metapenaeus joyneri. Morphometric analysis indicated that infested male and female shrimp have slightly, but significantly, lower body weight than uninfested shrimp of the same carapace length. While the parasites sterilize their hosts, the low infestation rate (0·53%) appears not to pose a threat to the shrimp fisheries in the Zhujiang estuary.  相似文献   

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《Journal of Natural History》2012,46(37-40):2537-2542
The earliest report on radiolarians from the Arctic Ocean (north of the Arctic Circle) was provided by H. B. Brady (1878 Brady, H. B. 1878. On the reticularian and radiolarian Rhizopoda (Foraminifera and Polycystina) of the North‐Polar Expedition of 1875–76.. Annals and Magazine of Natural History, Series 5, 1: 425440. [Taylor & Francis Online] [Google Scholar]). He documented the occurrences of 10 genera from soundings in northern Baffin Bay and north of Greenland, but he did not illustrate any specimens in his report. We have re‐examined Brady's original slide collection, housed at the Natural History Museum, London (NHM), in order to refine his radiolarian identifications to species level. We have identified 11 radiolarian taxa in his slides, but some are definitely more characteristic of tropical oceans rather than high northern latitudes. We conclude that this is most likely due to sample contamination or misidentification of samples. Therefore, the actual occurrence of tropically affiliated radiolarians recorded from the Arctic is uncertain and should be regarded with suspicion.  相似文献   

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《Journal of Natural History》2012,46(7-8):479-488
The snakes of the genus Thermophis, including two species (Thermophis baileyi and Thermophis zhaoermii), which are found only on the Qinghai‐Xizang Plateau, were studied to determine the phylogenetic position of the genus within the broad superfamily Colubroidea. In this study, T. baileyi from two different localities in Xizang and T. zhaoermii from western Sichuan formed a monophyletic group as determined using Bayesian and likelihood methods of phylogenetic inference. Based on the nucleotide sequence of the cyt b and c‐mos genes, Thermophis appeared to be a member of the subfamily Xenodontinae, which prior to this finding had been confined to a New World distribution. The molecular data also indicate a large genetic distance between T. baileyi and T. zhaoermii, which strengthens the validity of the new species: T. zhaoermii.  相似文献   

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《Journal of Natural History》2012,46(7):1021-1058
A report of the Leucosiidae collected during the Albatross Philippines expedition 1907–1910 is given. A total of 36 species in 17 genera are treated, with one genus (Heterolithadia) and nine species (Alox rugosum, Arcania elongata, Arcania globata, Heterolithadia fallax, Myra acutidens, Leucosia craniolaris, L. galantua, L. perlatta and Nucia tuberculosa) being new records for the Philippines and one species being new. This brings the total number of species known from the Philippines to 64, in 22 genera. A complete list of Philippine Leucosiidae is provided.  相似文献   

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《Journal of Natural History》2012,46(26):2409-2479
The majority of the 58 species discussed, including 10 new species, were collected by scuba divers at 5–10?m in waters around Australia. Species are from Leptoclinides (11), Polysyncraton (11), Didemnum (19), Trididemnum (7), Lissoclinum (8), Clitella (1), and Diplosoma (1), and new species are in all except Trididemnum and Diplosoma. Additional characters (including a pyloric vesicle reported previously in the Holozoidae and several unrelated didemnid taxa) have been detected for the monotypic genus Clitella Kott, , which is recorded for only the second time. A review of known Australian ascidian species confirms the Didemnidae as the most speciose ascidian family in these waters. In this family, there appears not to be appreciable gene flow between tropical and temperate waters and few species have a continuous tropical–temperate range. A preponderance of Western Pacific non‐indigenous species is in the north, while indigenous species, some probably isolated from related tropical ones, are dominant in the temperate waters of the southern half of the continent. Although intraspecific variation and convergence obscures species differences, some aspects of the living organisms detected in in situ photographs contribute to identification. Keys to Australian didemnid species described since the publication of the Australian Ascidiacea part 4, Didemnidae (Kott ) are included.  相似文献   

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《Journal of Natural History》2012,46(33-34):2173-2192
Variations in reproductive modes, egg production, and the effects of parental care on hatching success are compared between Pleioplana atomata and Imogine zebra. Pleioplana atomata transfers sperm via true copulation, whereas I. zebra dermally impregnates spermatophores onto the dorsal surface of partners. Pleioplana atomata lays up to 750 large eggs over a 6‐week period, and I. zebra individuals lay up to 1346 small eggs in 12 days. Female fecundity is positively correlated with body size in both species. Developmental time lines are temperature‐dependent, and juvenile worms hatch after 3 and 6 weeks for I. zebra and P. atomata, respectively. Covering of egg masses by the adult is observed for both species and although this parental care is not necessary for egg development or hatching, it plays a significant role in the hatching success of P. atomata. In I. zebra, parental covering of egg masses may play a role in eggshell development.  相似文献   

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《Journal of Natural History》2012,46(33-34):2243-2256
The Indonesian island Sulawesi is well known for its fascinating fauna. Among the atyid and palaemonid freshwater shrimps described from Sulawesi are also a number of endemic species. In contrast, freshwater shrimps have never been reported from the nearby and smaller Peleng Island. Here we describe Caridina thomasi sp. nov. as a first record of an atyid freshwater shrimp from Peleng and compare it with atyids from Sulawesi and other localities. The new species is probably endemic to the island and shows some characters never described in the genus Caridina before. However, a molecular phylogeny of atyid shrimps from the Indo‐West Pacific based on mitochondrial DNA (16S) places C. thomasi within a clade of typical species of Caridina. We tentatively assign the new species to the genus Caridina and discuss the possibility of future changes in the classification of species in this genus.  相似文献   

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《Journal of Natural History》2012,46(45-48):2979-2993
Analysis of the female life history of the poorly studied endemic Balkan lizard species Dinarolacerta mosorensis was conducted on three population samples from Montenegro. One clutch is produced annually. Females mature at body sizes of 56–57 mm snout–vent length (SVL), attained at age 3–4 years. SVL increases with age. The average clutch size ranged from 4.3 to 5.2 eggs, and was significantly positively correlated with maternal SVL in two population samples. There were no trade‐offs between egg size/offspring size and clutch size, nor between variation in egg size/offspring size and maternal SVL. The incubation period averaged 26.5 days, while hatching success in captivity was 72%. Significant positive correlations were found between the hatchling mass and egg mass and size, and also between the hatchling total length and egg width and volume. There was a significant negative relationship between the hatchling mass and incubation duration.  相似文献   

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