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1.

The authors monitored five maternity colonies of Plecotus austriacus to obtain data about phenology, roosting, and emergence behaviour. The bats occupied their roosts between April and October, with maximum colony sizes in August. Roosting sites in the attic’s roof ridge and temperatures of 20–25°C were favoured. Also considering the small colony (maximum 59) and cluster sizes (maximum 13 bats), P. austriacus behaved less thermophilic than other attic-dwelling species. During low temperatures, the bats chose small crevice-like roosting sites to compensate for that; during daytime, many bats remained hidden in crevices. Emergence began approximately 30 min after sunset; the bats used multiple, preferably crevice-like openings. P. austriacus left its summer roosts comparatively late; renovation works should, therefore, not start before November. For monitoring purposes, we recommend two to three emergence countings outside the attics in early August during warm weather, alongside two attic inspections 1–2 h before emergence for offspring monitoring.

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2.
Butterflyfish are among the most iconic of the coral reef fishes and represent a model system to study general questions of biogeography, evolution and population genetics. We assembled and annotated the genome sequence of the blacktail butterflyfish (Chaetodon austriacus), an Arabian region endemic species that is reliant on coral reefs for food and shelter. Using available bony fish (superclass Osteichthyes) genomes as a reference, a total of 28 926 high‐quality protein‐coding genes were predicted from 13 967 assembled scaffolds. The quality and completeness of the draft genome of C. austriacus suggest that it has the potential to serve as a resource for studies on the co‐evolution of reef fish adaptations to the unique Red Sea environment, as well as a comparison of gene sequences between closely related congeneric species of butterflyfish distributed more broadly across the tropical Indo‐Pacific.  相似文献   

3.
Butterflyfishes (Chaetodontidae) from the reefs of Ly Son Archipelago (northern Central Vietnam) are reviewed. In total, 16 species of chaetodontids from three genera (Chaetodon, Forcipiger, and Heniochus) are found. All species are documented by underwater photos, and they have not been registered off Ly Son Islands before. A comparison of chaetodontid faunas off Ly Son, Cu Lao Cham, and Paracel islands; in the Gulf of Tonkin; and in southern Central Vietnam is conducted.  相似文献   

4.
A total of 2,868 individuals of 47 species of chaetodontids were examined for faustulids at seven major localities in the Tropical Indo-West Pacific (TIWP). Combined morphological and molecular analyses allowed us to describe Paradiscogaster oxleyi n. sp. from three localities in the TIWP and in three host species, Chaetodon lunulatus Quoy & Gaimard (type-host), C. ornatissimus Cuvier and C. meyeri Bloch & Schneider. Molecular analysis of the ITS2 region of rDNA from two host species and three localities supports the morphology-based conclusion that P. oxleyi n. sp. is the same species at the three localities. Paradiscogaster flindersi Bray, Cribb & Barker, 1994 is reported from three new localities in the TIWP and is now known from 13 chaetodontid species. Sequences from samples consistent with P. flindersi differed from those from P. oxleyi n. sp. in 11–12 base pairs. The host ranges of the two species overlap broadly. Neither species was found in French Polynesia but both were found at Swain Reefs on the Great Barrier Reef. Only one of the two species was found at each of the five other sites. Both species occur almost exclusively in specialist corallivores allowing the inference that the metacercariae occur in corals. Finally, a key to the species of Paradiscogaster is provided.  相似文献   

5.
This study used three different methods to ascertain dietary composition for 21 Chaetodontidae species co-occurring on a single fringing reef in Derawan Island, East Kalimantan, Indonesia. The combination of in situ feeding observations, examination of gut contents and stable-isotope analyses was expected to identify previously unresolved prey items that contribute to dietary separation. In situ feeding observations identified five species that feed predominantly on anthozoans ( Chaetodon baronessa , Chaetodon bennetti , Chaetodon lunulatus , Chaetodon punctatofasciatus and Chaetodon speculum ). Stable-isotope ratios for these species, as well as for Chaetodon ornatissimus (for which no feeding observations were completed), were very similar and consistent with diets comprising mostly anthozoans. Feeding observations, however, showed that they mostly fed on different coral species, while the identifiable portion of their gut contents showed clear separation based on cryptic dietary components. For example, C. baronessa and C. bennetti appeared to ingest annelid worms during the course of coral feeding, whereas gut contents of C. punctatofasciatus and C. speculum were dominated by crustaceans. In situ feeding observations further identified the following groups: coral–bottom feeders, bottom feeders, sponge feeders and pelagic feeders, feeding on a wide variety of prey items such as Annelida, Crustacea, Cnidaria, Mollusca and macroalgae. Overall, many chaetodontid species had similar reliance on major prey items ( e.g . anthozoans or polychaetes) but differed greatly in the minor prey items that they utilized. Partitioning of minor prey items may be important in reducing interspecific competition and facilitating coexistence of chaetodontids on coral reefs.  相似文献   

6.
Pair behavior and spacing in butterflyfishes (Chaetodontidae)   总被引:2,自引:0,他引:2  
Synopsis Three species of butterflyfishes, Chaetodon multicinctus, C. quadrimaculatus and C. ornatissimus were observed over a seven month period on the Kona coast of the island of Hawaii. All three species were found to be exclusively paired. However, C. quadrimaculatus and C. ornatissimus pair mates spent less time together and had longer separations and fewer meetings than did C. multicinctus pairs. All three species occupied and defended intraspecifically exclusive territories. Territories were maintained through mutual avoidance with occasional agonistic interactions.  相似文献   

7.
Summary Phylogenetic analysis based on sequence data of the mitochondrial COI gene confirms the species status of the recently described Lasius austriacus. The five haplotypes of L. austriacus do not cluster according to their geographic origin, indicating a recent gene flow among the populations. The molecular data corroborate the morphology based hypothesis that L. austriacus belongs to the Lasius (Lasius s.str.) brunneus group. The invasive species Lasius neglectus forms a sister taxon with L. turcicus, both next related to L. austriacus. Other phylogenetic relationships within the genus Lasius are in accordance with morphological data.First data on the bionomics of L. austriacus are discussed in context with its phylogenetic position. Based on gyne and male morphology, excavations of nests, pitfall trapping and observations in formicaries, we hypothesize that L. austriacus is a mainly hypogaeic, monogynous species with nuptial flight. These are characters of the Lasius brunneus group in general, except the polygynous-polycalic, intranidally copulating L. neglectus. Aggression tests, however, revealed non-aggressive behaviour (antennation) between separated L. austriacus populations, but pronounced interspecific aggression against L. neglectus. This confirms the species status of L. austriacus and indicates a reduced level of intraspecific aggression, similar to L. neglectus.The status of L. austriacus as a native species in Central Europe is confirmed.Received 10 February 2003; revised 24 June 2003; accepted 23 July 2003.  相似文献   

8.
9.
In Crawford Lake, a small meromictic water body in southern Ontario, Canada, the life cycles of planktonic Chaoborus flavicans and C. punctipennis were out of phase by about two months, the former pupating from mid May through mid June and the latter from July through September. C. flavicans possibly produced a second annual generation. Fourth instars of both species were strong diel migrators and occupied similar strata at most times. C. punctipennis fourth instar diet consisted almost entirely of rotifers. C. flavicans ate rotifers but fed heavily also on daphnids in May and August. C. punctipennis fourth instars showed little growth until early spring, possibly owing to a sparseness of rotifers, then grew rapidly until pupation. C. flavicans had a slow, but relatively constant growth rate at all times during the open water season, presumably because its greater mouth gape allowed it a wider range of food items.  相似文献   

10.
The diversity, ecology, and seasonality for sand flies from two localities in Jenin District, the Palestinian Territories, were studied. A total of 12,579 sand flies (5,420 Phlebotomus and 7,159 Sergentomyia) were collected during the study period. The genera Phlebotomus and Sergentomyia are represented by 13 and nine species and subspecies, respectively. Species account was given for all collected species. CDC light traps yielded 7,649 (60.8%) of the total captured sand flies, while sticky traps and aspirators contributed to 36.4 and 2.8% of the total collected specimens, respectively. Phlebotomus sergenti and P. syriacus showed two peaks, one in July and one in October. Phlebotomus tobbi showed one peak towards the end of the summer in September and August, while P. papatasi showed a bimodal peaks pattern, one in June and one in October. Phlebotomus canaaniticus showed a peak in August. P. perfiliewi transcaucasicus and P. neglectus showed a peak in October. Sergentomyia dentata showed one peak in August and increasing numbers from June to August, declining afterwards. Other species, such as S. theodori, had one peak in June, S. taizi had steady numbers across the summer, and S. christophersi had a peak in August.  相似文献   

11.
Photosynthetic pigments, C, N, and P tissue composition, and photosynthetic rate were measured from April to October in the brown alga Phyllariopsis purpurascens (C. Agardh) Henry et South (Laminariales, Phaeophyta) growing at a 30-m depth in the Strait of Gibraltar. Ir-radiance reaching the population ranged from 13.5 to 27.5 mol.m-2.mo-1. The available light for this species, expressed as a percentage of the irradiance above the water, was 1.8%. Dissolved inorganic nitrogen forms, NO3-and NH4+, were constant from April to October, whereas phosphate was depleted in August. Chlorophyll a decreased from 520.0 ± 165.0 to 199.6 ± 159.9 μg.g-1 dry weight; in contrast, chlorophyll c and carotenoids did not change until September but increased threefold in October. C:N and N:P ratios changed in the same way and in the same range. They were constant until July but increased from 15–17 up to 42 (C:N) and from 14 to 40 (N:P) in October, suggesting a severe P limitation of growth of this species. The dark respiration rate and the light compensation point were constant from April to October (0.5 ± 0.1 μmol O2. m-2.s-1 and 6.5 ± 0.2 μmol.m-2. s-1, respectively), whereas the maximum rate of apparent photosynthesis, light onset saturation parameter, and half saturation constant for light were maximum in April to May (3.7 μmol O2. m-2.s-1and 40 and 41.5 μmol.m-2. s-1, respectively) and October (3.6 μmol O2. m-2.s-1 and 50 and 53.7 μmol.m-2. s-1, respectively). They were minimum in August (1.2 μmol O2.m-2.s-1 and 11.3 and 12 μmol.m-2.s-1, respectively). These minimum figures yielded a negative carbon budget in August and 0 in September, whereas it was positive the rest of the year. Photosynthetic efficiency, estimated by the ratio between maximum apparent photosynthesis and light half saturation constant, showed a strong agreement with productivity measured by means of an independent method. These results indicate that lamina expansion in this species is controlled by photosynthetic efficiency.  相似文献   

12.
The length–weight relationships were determined for two fish species (Callionymus curvicornis Valenciennes, 1837 and Johnius fasciatus Chu, Lo & Wu, 1963) belonging to two families. Fish samples were collected using commercial trawls (mesh sizes: 70 mm) and the frequency of use three times during each sampling period from Sanniang Bay, China. Samples were collected quarterly from October 2016 to July 2017. The allometric coefficient (b) of length–weight relationship varied from 2.75 for Callionymus curvicornis to 2.92 for Johnius fasciatus. Length–weight relationships for these two fish species were determined for the first time.  相似文献   

13.
广东省蛇类新纪录-双全白环蛇   总被引:1,自引:0,他引:1  
2011年9~10月,分别在广东省乳源瑶族自治县南岭国家森林公园和始兴县车八岭国家级自然保护区采集到游蛇科(Colubridae)白环蛇属(Lycodon)标本3号,经鉴定为双全白环蛇(Lfasciatus),为广东省蛇类新纪录.  相似文献   

14.
Marinomonas sp. NJ522, isolated from Antarctic sea ice, produces a cold-active iron superoxide dismutase (SOD; EC 1.15.1.1). The purified SOD was dimeric and had an approx. Mr of 48 kDa. Highest activity was detected from pH 8 to 10 and at 40 °C (assayed over 10 min). Activity at 0 °C was nearly 35% of the maximum activity. Received 25 August 2005; Revisions requested 30 August 2005 and 26 September 2005; Revisions received 12 September 2005 and 25 October 2005; Accepted 1 November 2005  相似文献   

15.
This study examined within‐reef distributions for 19 species of butterflyfishes (Chaetodontidae) at Lizard Island, northern Great Barrier Reef, Australia, and compared spatial patterns of abundance among species with contrasting diets. Spatial variation in abundance of butterflyfishes was most prominent among physiognomic reef zones mainly due to significant zonation of eight species, including four obligate hard‐coral feeders (Chaetodon trifascialis, Chaetodon baronessa, Chaetodon plebeius and Chaetodon lunulatus) and four generalist species (Chaetodon auriga, Chaetodon citrinellus, Chaetodon kleinii and Chaetodon rafflesi). Distributions of obligate hard‐coral feeders were closely associated with spatial variation in percentage cover of scleractinian corals, but no more restricted compared with facultative hard‐coral feeders or non‐coral feeders. Species with highest dietary specialization (C. trifascialis and C. baronessa), however, exhibited the most pronounced zonation patterns and were restricted to habitats with greatest abundance of their preferred prey. While there are conspicuous links between dietary specialization v. spatial patterns in abundance of butterflyfishes, it remains unclear whether dietary specialization is the cause or consequence of more restricted distributions.  相似文献   

16.
ABSTRACT

Metamorphosis season of megalopae to the first crab stage in snow crab Chionoecetes opilio and red snow crab C. japonicus was inferred by culturing wild-born megalopae collected from the Sea of Japan. Metamorphosis occurred from late June to late July (mainly in July) in snow crab, and from early July to early October (mainly from August to September) in red snow crab. The number of days required from the time of collection to metamorphosis was less than the intermoult period previously reported for snow crab megalopae. However, the developmental period of the megalopae was estimated as substantially longer in red snow crab than in snow crab. Previous studies have shown that the hatching season and the period of the zoeal stage in both two species are similar. These results suggest that a different metamorphosis season between the two species would be due to a difference in their megalopal intermoult period.  相似文献   

17.
Synopsis The ranging and feeding behaviour of the butterflyfishChaetodon austriacus (Chaetodontidae) was studied at eight sites along the Red Sea coast of Saudi Arabia. This species was strongly paired and was found to defend territories intraspecifically, predominantly by display and non-aggressive advertisement. Frequencies of overt aggression were relatively low. Two other species of butterflyfish were aggressed against occasionally, but this did not appear to be space-related.C. austriacus fed entirely on scleractinian corals, primarilyAcropora, but included a variety of other genera in the diet. Territories appeared to be defended primarily for feeding and were significantly larger (1.6 times) at 10–15 m on the fore-reef slope than at the 1–2 m deep reef-edge. The availability of coral differed by a similar amount between depths, cover being 1.7 times greater in shallow water. Feeding rates did not differ significantly between depths.  相似文献   

18.
Patterns of reproductive ontogeny in four species of coral reef wrasses (F: Labridae) Hemigymnus melapterus, Hemigymnus fasciatus, Cheilinus fasciatus and Oxycheilinus digramma were investigated. Populations of each species were sampled from two island groups of the central Great Barrier Reef (GBR), Australia, and from coral reefs in the central Philippines. These three sampling locations span 30° of latitude. The GBR and Philippine reefs experience biologically significant differences in water temperature, geography and human activity. The studied wrasses are effectively unfished in Australia but heavily fished in the Philippines. Gonad weights, histology and demographic data were obtained across the entire size and age range of H. melapterus, C. fasciatus and O. digramma from all locations. Analysis identified three processes of male recruitment: functional gonochorism and both forms of protogynous hermaphroditism, monandry and diandry. The expression of these distinct sexual ontogenies was locality dependent. Populations of H. melapterus, H. fasciatus, C. fasciatus and O. digramma on the GBR showed consistently uniform patterns of sexual ontogeny, with all species being exclusively monandric. H. melapterus, C. fasciatus and O. digramma in the Philippines displayed complex sexual ontogenies, with all species showing histological evidence of both diandry and functional gonochorism. Reproductive investment in gonadal tissue, and population sex structure, also differed between GBR and Philippine coral reefs. Philippine populations had substantially lower gonado-somatic indices than populations on the GBR. Nonetheless, Philippine populations matured more rapidly and displayed a protracted timing of sex change over a large size and age range. Thus, mature females appeared earlier and persisted later into ontogeny in the Philippines than on GBR reefs. Protracted timing of sex change on Philippine reefs is likely linked to the presence of primary males in the population, which is known to reduce the strength of selection for mature females to undergo sex change and become male. Hypotheses based on social structure of fish populations, environmental factors and evolutionary history were developed to account for the different patterns of sexual ontogeny in the focal wrasses.  相似文献   

19.
This study examined the dietary habits and functional composition of butterflyfishes in the Chagos Archipelago, central Indian Ocean. Eighteen species of butterflyfishes were recorded in Chagos, including six obligate corallivores (Chaetodon bennetti, Chaetodon guttatissimus, Chaetodon meyeri, Chaetodon trifascialis, Chaetodon trifasciatus and Chaetodon zanzibarensis), five facultative corallivores (Chaetodon auriga, Chaetodon falcula, Chaetodon interruptus, Chaetodon kleinii and Chaetodon madagaskariensis), two non‐corallivores (Chaetodon lunula and Chaetodon xanthocephalus) and a further five species (Chaetodon citrinellus, Chaetodon lineolatus, Heimitaurichthys zoster, Heniochus monoceros and Forcipiger flavissimus), for which local dietary habits were not studied. There were marked differences in the abundance of butterflyfishes among sites and between reef zones, mostly associated with variation in abundance of scleractinian corals. Obligate coral‐feeding species (mostly C. trifascialis) dominated across all sites. This study suggests that coral feeding and high levels of dietary specialization contribute to high population‐level fitness among coral reef butterflyfishes. Despite being more vulnerable to habitat disturbances and coral loss, it appears likely that specialist coral‐feeding butterflyfishes are also much more resilient to occasional disturbances, and therefore dominate in a wide range of coral reef habitats.  相似文献   

20.
The ecology and life histories of Orconectes rusticus rusticus (GIRARD) and Cambarus tenebrosus HAY were investigated in a spring stream, Doe Run, Meade County, Kentucky, from September 1962 through September 1964. Differences in ecology of these species were most clearly seen in their habitat preferences and distributions in the stream, their feeding habits, responses to temperature, and infestations by an harpacticoid copepod Attheyella carolinensis CHAPPUIS, and in other life history phenomena, particularly with regard to reproduction and growth. Cambarus tenebrosus was most abundant in the constant temperature areas of the headwaters of Doe Run. Orconectes r. rusticus was found only in the lower three-fourths of the stream. Water temperatures in the headwater area may have been too low (12 — 14 C) for optimal growth of the crayfish had it existed there. Adults of C. tenebrosus were primarily hypogean, but young and subadults frequented the open stream environment. Orconectes r. rusticus was primarily an open stream inhabitant, and was sympatric with C. tenebrosus subadults and young in the downstream areas. When C. tenebrosus occurred in the open environment, it was most abundant in association with vegetation, and hence, was more heavily infested with A. carolinensis than O. r. rusticus. Detritus, mainly from fallen leaves and marl grazings, apparently formed the most important component of the diet of O. r. rusticus. Vascular plants, mainly fallen leaves from the riparian vegetation, constituted the main portion of the diet of C. tenebrosus; filamentous algae were widely used where and when they were present. Orconectes r. rusticus eggs hatch in May. These hatchlings become mature in 15 months and females oviposit after 22 – 24 months from March —May. Sexual maturity is attained at a carapace length of about 18 mm; maximum size is 45 mm. Most animals die after about 2.5 years; however, some live for three years. Molting activity ceases in winter. Cambarus tenebrosus young hatch in July and August. Most hatchlings remain in the burrows until October and November at which time they emerge in response to dominance behavior. Growth occurs throughout the winter months, and sexual maturity is attained in 20 – 22 months when the crayfish are about 40 mm in carapace length. Mature females oviposit during June and July after about 22–23 months, and probably again after 34–35 months. Mating occurs during the winter and spring. In Doe Run, maximum size attained is 65 mm carapace length. Cambarus tenebrosus probably lives for 36 – 38 months.  相似文献   

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