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1.
The internal anatomy of the barbels of the common sawshark Pristiophorus cirratus was examined with light microscopy to clarify their sensory role. No sensory structures such as taste buds (chemoreception), ampullae of Lorenzini (electroreception) or free neuromasts (lateral line mechanoreception) could be located in the barbels. The presence of bundles of nerve fibres, however, indicates a tactile function for the barbels. Conveyance of information regarding potentially damaging stimuli (nociception) and temperature (thermoception) cannot be excluded at this stage. It is hypothesized that the barbels are used by P. cirratus to locate prey in both the water column and on the substratum via wake detection and sensing changes in surface texture. The barbels may also be involved in the detection of water currents for rheotaxis. Regression analyses on P. cirratus morphometric data showed that the width of the rostrum at two sections (the barbels and the rostrum tip) does not significantly correlate with total length. The regression analyses also suggested that the barbels of P. cirratus may be lateralised.  相似文献   

2.
In protected areas of the southern Chilean coastline, the barnacle Jehlius cirratus dominates the upper intertidal zone, the bivalve Perumytilus purpuratus is the dominating species in the intermediate zone and Mytilus chilensis in the middle-lower zone. Varying degrees of aerial respiration were observed in the laboratory for these three sessile invertebrates: 80–100% of the immersed oxygen uptake for Jehlius cirratus, 30–50% for Perumytilus purpuratus and 5–15% for Mytilus chilensis. The pyruvate kinase/phosphoenolpyruvate carboxykinase (PK/PEPCK) ratio (adductor muscle) was higher for P. purpuratus than for M. chilensis. J. cirratus had no PEPCK activity in total soft tissues, under the assay conditions used in this study, and PK activity was higher for the cirriped than that of both bivalves. Succinate was produced in both mussels when exposed to hypoxic conditions, but it was not detected in J. cirratus. The kinetic parameters of the PK revealed that M. chilensis presented the highest 0.5 value for PEP and J. cirratus the lowest. Alanine inhibited the PK from M. chilensis to a greater extent (higher nH value) and did not affect the PK of the cirriped. This latter enzyme also presented a marked substrate inhibition, above PEP concentrations of 0.5 mM. The evidence suggests that organisms inhabiting the upper intertidal zone could utilize an aerobic metabolism, given their high aerial respiration capacity, and that the succinate anaerobic pathway could be a more important metabolic strategy in species of the middle-lower intertidal zone. The physiological and biochemical capacities of these three species could thus be correlated with their vertical distribution in the intertidal rocky shore.  相似文献   

3.
Annelids provide suitable models for studying regeneration. By now, comprehensive information is restricted to only a few taxa. For many other annelids, comparative data are scarce or even missing. Here, we describe the regeneration of a member of the Cirratulus cirratus species complex. Using phalloidin‐labeling and antibody‐stainings combined with subsequent confocal laser scanning microscopy, we provide data about the organization of body wall musculature and nervous system of intact specimens, as well as about anteriorly regenerating specimens. Our analyses show that C. cf. cirratus exhibits a prominent longitudinal muscle layer forming a dorsal muscle plate, two ventral muscle strands and a ventral‐median muscle fiber. The circular musculature forms closed rings which are interrupted in the area of parapodia. The nervous system of C. cf. cirratus shows a typical rope‐ladder like arrangement and the circumesophageal connectives exhibit two separate roots leading to the brain. During regeneration, the nervous system redevelops remarkably earlier than the musculature, first constituting a tripartite loop‐like structure which later become the circumesophageal connectives. Regeneration of longitudinal musculature starts with diffuse ingrowth and subsequent structuring into the blastema. In contrast, circular musculature develops independently inside the blastema. Our findings constitute the first analysis of regeneration for a member of the Cirratuliformia on a structural level. Summarizing the regeneration process in C. cf. cirratus, five main phases can be subdivided: 1) wound closure, 2) blastema formation, 3) blastema differentiation, 4) resegmentation, and 5) growth, respectively elongation. Additionally, the described tripartite loop‐like structure of the regenerating nervous system has not been reported for any other annelid taxon. In contrast, the regeneration of circular and longitudinal musculature originating from different groups of cells seems to be a general pattern in annelid regeneration. J. Morphol. 275:1418–1430, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

4.
The following species are described from Platax spp.: Neomultitestis aspidogastriformis n. sp., from P. teira, off Heron Island, Queensland, which can be distinguished from its congeners by the transversely elongate ventral sucker divided into three loculi and probably by testis number; Multitestis magnacetabulum Mamaev, 1970, from P. teira, off Heron Island, Queensland; Diploproctodaeum rutellum (Mamaev, 1970), from P. teira, off Heron Island, Queensland; Diploproctodaeum tsubameuo n. sp., from P. batavianus, from the Swain Reefs, off Queensland, which differs from its congeners in its overlapping, posteriorly attenuated testes and 38-55 ovarian lobes; and Diplocreadium sp., from P. batavianus, from the Swain Reefs, off Queensland.  相似文献   

5.
Several species of the family Petraliellidae were first described from the coast of Queensland, including the type species of Sinupetraliella, S. litoralis. These species are redescribed from type, or topotype specimens, and include Petraliella concinna, which has not been certainly found since its introduction in 1891; lectotype material is designated for P. buski and P. magna. Six other species are described from Queensland, P. crassocirca, P. dentilabris, P. dorsiporosa, Mucropetraliella bennetti, M. serrata and M. tuberosa. The species Mucropetraliella tuberosa is a new addition to the Queensland fauna and is described and illustrated here for the first time since its introduction in 1884. The characters of the family Petraliellidae are briefly discussed and the genera to which the Queensland species are assigned is reviewed. A taxonomic key to the ten Queensland petraliellid species described is also provided.  相似文献   

6.
Potential roles of the rostrum of sawsharks (Pristiophoridae), including predation and self‐defence, were assessed through a variety of inferential methods. Comparison of microwear on the surface of the rostral teeth of sawsharks and sawfishes (Pristidae) show that microwear patterns are alike and suggest that the elongate rostra in these two elasmobranch families are used for a similar purpose (predation). Raman spectroscopy indicates that the rostral teeth of both sawsharks and sawfishes are composed of hydroxyapatite, but differ in their collagen content. Sawfishes possess collagen throughout their rostral teeth whereas collagen is present only in the centre of the rostral teeth of sawsharks, which may relate to differences in ecological use. The ratio of rostrum length to total length in the common sawshark Pristiophorus cirratus was found to be similar to the largetooth sawfish Pristis pristis but not the knifetooth sawfish Anoxypristis cuspidata. Analysis of the stomach contents of P. cirratus indicates that the diet consists of demersal fishes and crustaceans, with shrimp from the family Pandalidae being the most important dietary component. No prey item showed evidence of wounds inflicted by the rostral teeth. In light of the similarities in microwear patterns, rostral tooth chemistry and diet with sawfishes, it is hypothesised that sawsharks use their rostrum in a similar manner for predation (sensing and capturing prey) and possibly for self‐defence.  相似文献   

7.
Three jars from the Hamburg Museum contained specimens of Branchiobdella minuta, presumably from the original Pierantoni (1912) material, and Cirrodrilus cirratus and C. uchidai from Yamaguchi's (1932a) collection. The head of a syntype of B. minuta was described and B. cheni becomes its junior subjective synonym. One specimen each of C. cirratus and C. uchidai was sectioned and described, particularly the male genitalia. The diet of all three branchiobdellids consists of microorganisms. In Cirrodrilus sp. basic protein granules were demonstrated in the gland cells of the intestine and its chloragogen cells. The peristomial and lateral epidermal gland cell secretions were characterized histochemically.  相似文献   

8.
Abstract

Across 88 sites 9 species were found, with Anaplectus granulosus at 56 sites, Plectus parietinus at 47, P. longicaudatus at 30, P. parvus at 15, P. cirratus and Wilsonema otophorum at 11, P. armatus and A. porosus at 4, and Tylocephalus auriculatus at 1 site. A key to Anaplectus males is given. For nine sites mean length of female A. granulosus is negatively correlated with mean annual air temperature. The most diverse fauna comprised six species in Kaitoke silt loam; it appears that faunal diversity increases with higher rainfall. Species apparently coexist through separation in size and time. Tylocephalus was only found in soils with a thermic soil temperature regime.  相似文献   

9.
The eel goby Taenioides cirratus (Blyth, 1,860) is a small fish inhabits muddy bottoms of brackish-water in the Indo-West Pacific. It has invaded many inland freshwater lakes in China, such as the Chaohu Lake, Gaoyou Lake and Nansi Lake, and its population increased rapidly in these freshwater lakes in recent years. The age, growth and reproductive traits of T. cirratus invading the Chaohu Lake were studied. A total of 482 specimens (210 females, 204 males and 68 juveniles) with total length (TL) ranging from 9.4 to 20.6 cm were collected using the benthic fyke nets at monthly intervals from March 2018 to February 2019. The sagittal otolith was used for age determination. Monthly variation of marginal increment ratio indicated that the annual forming of opaque band on sagittal otolith was completed during March and April. For both sexes, only four (from 0+ to 3+ years) age groups were observed and 1+ and 2+ years age individuals dominated the population. Back calculated length at age showed males grew faster than females. Both sexes reached maturity at 1+ year age and the TL at first maturity (TL50) was 12.6 cm for females and 11.9 cm for males. Monthly variation of gonado-somatic index indicated that the spawning occurred from May to August. The fecundity ranged from 967 ova to 5,114 ova, with a mean of 3,205 ova. Our study provides a comprehensive data on the key life history traits of T. cirratus for the first time.  相似文献   

10.
An important prediction from game theory is that the value of a resource will influence the level to which an animal is willing to escalate during conflict with conspecific rivals. Here we use this prediction as the rationale for experiments aimed at determining whether escalation decisions made by predators are influenced by the presence of preferred prey. The predators we use are adult individuals of Portia fimbriata, a jumping-spider (Salticidae) species from Queensland (Australia). P. fimbriata is known to prefer other salticid species as prey and can detect the odour of Jacksonoides queenslandicus, this being an especially common salticid species in the Queensland habitat. Here we show that, for P. fimbriata females, the odour of J. queenslandicus primes escalation of vision-based conflict. However, for P. fimbriata males, no comparable effect was found. These findings suggest intrasexual competition for prey is more important to females than to males.  相似文献   

11.
12.
The new peptide antibiotics have been obtained from the culture filtrate of a streptomycete, strain 248-Sq2, isolated from a soil sample collected at Nagano Prefecture, Japan.

On the basis of taxonomic studies, the producing organisms is designated as Streptomyces cirratus. Two active principles are named cirratiomycin A and B.

These antibiotics exhibit a narrow range of activities against Lactobacillus casei and some strains of Streptococcus and Mycobacterium.  相似文献   

13.
Pycnadenoides pagrosomi Yamaguti, 1938 and P. reversati n. sp. from Pagrus auratus (Sparidae) and P. invenustus n. sp. from Nemadactylus valenciennesi (Cheilodactylidae) are described from the temperate marine waters off south-west Western Australia and south-east Queensland. The difference in the anterior extent of the vitelline follicles observed in P. reversati n. sp. recovered from off south-east Queensland waters and the material from off Western Australia is discussed. P. reversati n. sp. is distinguished from P. pagrosomi mainly in the position of the genital pore and in the arrangement of the testes, and from P. invenustus n. sp. in the posterior extent of the cirrus-sac. P. reversati belongs to the group of species with a short cirrus-sac and P. invenustus to the group with the cirrus-sac reaching into the anterior hindbody.  相似文献   

14.
The yellow-footed rock-wallaby Petrogale xanthopus is considered to be potentially vulnerable to extinction. This wallaby inhabits naturally disjunct rocky outcrops which could restrict dispersal between populations, but the extent to which that occurs is unknown. Genetic differences between populations were assessed using mitochondrial DNA (control region) sequencing and analysis of variation at four microsatellite loci among three geographically close sites in south-west Queensland (P. x. celeris) and, for mtDNA only, samples from South Australia (P. x. xanthopus) as well. Populations from South Australia and Queensland had phylogenetically distinct mtDNA, supporting the present classification of these two groups as evolutionarily distinct entities. Within Queensland, populations separated by 70 km of unsuitable habitat differed significantly for mtDNA and at microsatellite loci. Populations separated by 10 km of apparently suitable habitat had statistically homogeneous mtDNA, but a significant difference in allele frequency at one microsatellite locus. Tests for Hardy-Weinberg equilibrium and micro-geographical variation at microsatellite loci did not detect any substructuring between two wallaby aggregations within a colony encircling a single rock outcrop. Although the present study was limited by small sample sizes at two of the three Queensland locations examined, the genetic results suggest that dispersal between colonies is limited, consistent with an ecological study of dispersal at one of the sites. Considering both the genetic and ecological data, we suggest that management of yellow-footed rock-wallabies should treat each colony as an independent unit and that conservation of the Queensland and South Australian populations as separate entities is warranted.  相似文献   

15.
Aim Caridean shrimp are diverse and abundant inhabitants of seagrass beds. Anthropogenic disturbances have already reduced and fragmented seagrass habitat, and the rate of change is likely to increase in the future. It is therefore becoming increasingly important to build a basis of understanding of connectivity among populations of seagrass‐associated fauna. Phycomenes zostericola is closely associated with seagrass and makes an ideal study species with which to explore patterns of connectivity and the influence of biogeographic boundaries and historical sea‐level changes on seagrass‐associated species. We hypothesized that strong currents and the high potential of P. zostericola for dispersal and adult movement would result, for the most part, in panmixia. We also hypothesized that if structure was evident, it would occur close to known biogeographic boundaries in Queensland. Location Phycomenes zostericola is an abundant shrimp species distributed throughout Queensland’s seagrass habitats. Nineteen seagrass sites from the Torres Strait Islands and Queensland coastlines were sampled. Methods Molecular sequence data for a 590 base pair fragment of the mitochondrial gene cytochrome c oxidase subunit I (COI) was analysed for 279 specimens of P. zostericola. Phylogeographic patterns were analysed using nested clade phylogeographic analysis (NCPA); an isolation‐by‐distance effect was tested using a Mantel test; the effect of biogeographic boundaries was tested using an analysis of molecular variance (AMOVA), and also a spatial analysis of molecular variance (SAMOVA); demographic expansions were tested for using Tajima’s D, Fu’s FS and timing estimated using mismatch analysis; the timing of vicariant events was estimated using coalescent analysis (im program). Results Contrary to our original hypothesis, the strong marine currents are not a connective influence among populations of P. zostericola. Regional genetic structure and an isolation‐by‐distance effect are enhanced by existing coastal biogeographic boundaries. Population genetic structure and demographic history are intricately linked to the effects of a tumultuous Pleistocene sea‐level history on the Queensland continental shelf. Main conclusions Connectivity diminishes among populations of P. zostericola over scales larger than a few hundred kilometres. As seagrass habitats world‐wide become increasingly fragmented, low levels of connectivity will result in an isolated future for P. zostericola and other species reliant on seagrass as habitat.  相似文献   

16.
The following species are described, figured and/or recorded from the Great Barrier Reef at Heron Island or Lizard Island, Queensland, with comparative material reported from other areas of the ocean around Australia or New Guinea: Dinurus longisinus (new synonym: D. hippuri) from Seriola lalandi, Heron Island and Coryphaena hippurus, Papua New Guinea; Ectenurus trachuri from Caranx sexfasciatus, Diploprion bifasciatus, Pterocaesio marri, Seriola lalandi and Atherinomorus capricorniensis, Heron Island; Erilepturus hamati (with 25 new synonyms) from Lutjanus carponotatus, Lizard Island, Platycephalus bassensis, Coff's Harbour, NSW, P. fuscus, Coff's Harbour, NSW and Moreton Bay, Queensland, P. endrachtensis, Sillago analis, S. maculata, S. ciliata, Pseudorhombus arsius and Polydactylus sp. from Moreton Bay, Queensland and Lates calcarifer, Darwin, Northern Territory; Tubulovesicula angusticauda from Echeneis naucrates and Lethrinus miniatus, Heron Island and Anguilla reinhardtii, Moreton Bay and Bribie Island, Queensland; Elytrophalloides humerus from Trachinotus botla and T. coppingeri, Heron Island; Lecithochirium kawakawa from Euthynnus affinis Heron Island and Lizard Island: Lecithochirium cirrhiti (new synonyms: L. sammarae, L. nohu) from Sargocentron rubrum, Heron Island; Lecithochirium caesionis from Pterocaesio marri, heron Island; Plerurus digitatus (new synonyms: P. cynoglossi, P. atulis, P. scomberomori) from Plectropomus leopardus, Heron Island, Lutjanus erythropterus, Variola louti, Scomberomorus semifasciatus, Grammatorcynus bicarinatus and Carangoides embureyi, C. gymnostethoides, Lizard Island, Scomberomorus commerson, Heron Island, Lizard Island, New Britain, Papua New Guinea, Point Lookout, Queensland and Moreton Bay, Queensland, Euthynnus affinis Heron Island, Lizard Island and New Britain, Papua New Guinea, Sphyraena barracuda, Heron Island and Lizard Island, Scomberomorus munroi, S. queenslandicus and Saurida undosquamis, Moreton Bay, Queensland and Chirocentrus dorab, Bundaberg, Queensland. The Lecithochirium species-group Cirrhiti is considered indistiguishable from the species-group Lotellae.  相似文献   

17.
1 Paropsis atomaria Olivier represents an emergent pest of Eucalyptus plantations in Queensland and New South Wales, Australia. Most prior studies on the biology and control of P. atomaria have centred on populations from Canberra in the Australian Capital Territory, but the biological relationship between beetles from Canberra and those from up to 1500 km further north are unknown. 2 DNA markers were used to determine whether P. atomaria from Canberra are the same biological species as those from Eucalyptus forestry plantations in northern New South Wales and Queensland, where the beetle has become an important pest. Using the mitochondrial gene, cytochrome c oxidase I (COI), individuals collected from across the distribution of P. atomaria were investigated for haplotype diversity and levels of mitochondrial divergence. 3 Within P. atomaria, genetic distance averaged 0.5% across 23 unique haplotypes for 93 individuals, with an average of 14% difference between P. atomaria and the outgroup species, Paropsis obsoleta. Significant genetic structure was observed relative to geographical distribution, but not with respect to host plant species of origin. Greatest divergence was between the southern‐most sample site (Canberra) and northern sites in New South Wales and Queensland, indicating reduced gene flow between these regions. 4 Individuals from across eastern Australia belong to the same genetic species with population substructuring evident. Consequently, there is no evidence to suggest cryptic species complexes exist within the currently defined taxon. Continued implementation of control strategies for P. atomaria across its distribution is appropriate.  相似文献   

18.
SYNOPSIS. The gregarine order Archigregarinorida is redefined. The new family Selenidioididae is established in it, containing the genera Selenidioides n. g. with 11 species, Meroselenidium with 1 and Merogregarina with 1. The new family Exoschizonidae is also established in it, with 1 genus, Exoschizon, containing 1 species. The family Selenidiidae is transferred to the order Eugregarinorida in a new superfamily, Lecudinicae, and redefined to exclude the presence of merogony. As redefined, the family Selenidiidae contains the genera Selenidium with 33 species, Selenocystis with 1 and Ditrypanocystis with 2. The following new species are named: Selenidioides fanthami, S. hawesi, Selenidium mackinnonae, S. martinensis, S. rayi, Ditrypanocystis coxi. The following new combinations are introduced: Selenidioides axiferens, S. caulleryi, S. giganteum, S. hollandei, S. intraepitheliale, S. mesnili, S. metchnikovi, S. potamillae, S. sipunculi, Selenidium synaptae. In addition, the septate form from Cirratulus cirratus that was named Polyrhabdina cirratulus by Bogolepova (2) is renamed P. bogolepovae n. sp.  相似文献   

19.
ABSTRACT

Parthenium is a Weed of National Significance in Australia. Biological control of parthenium in Australia commenced in 1977 and since then nine insect species and two rust fungi have been introduced and established. Seven of them are widespread, however the time taken for field establishment varied widely between various agents, ranging from one to 15 years. Among them, the stem-galling Epiblema moth, the stem-boring Listronotus weevil, the seed-feeding Smicronyx weevil and the root-feeding Carmenta moth occur in all parthenium-infested areas at high population densities. The leaf-feeding Zygogramma beetle occurs only in central and southern Queensland, and not in northern Queensland. The parthenium summer rust occurs seasonally in central and northern Queensland, while the parthenium winter rust is more widespread in southern Queensland than in central Queensland, but does not occur in north Queensland. The sap-feeding Stobaera planthopper and the leaf-mining Bucculatrix moth established and are widespread, but their damage levels remain very low. The stem-galling Conotrachelus weevil and the stem-boring Platphalonidia moth are believed to be established, but at very low abundance. Biological control has resulted in significant reductions in the abundance and impact of parthenium in Australia. As a result, the area infested with parthenium in central Queensland has declined since the mid-1990s. Due to the absence of many of the effective agents in southern and south-eastern Queensland, agents from central Queensland are being redistributed there. Additionally, based on Australian success, many of these agents have also been introduced into other countries around the world.  相似文献   

20.
Prey manipulation through headfirst ingestion is a common foraging tactic in predatory taxa. Sawsharks possess a toothed rostrum that is thought to assist in prey capture, but the process from prey contact to ingestion is unknown. This study provides evidence of headfirst ingestion and possible prey orientation in situ through the use of cone beam CT scans in the common sawshark (Pristiophorus cirratus). CT scans provide an efficient method for assessing ingestion and proposing plausible behavioural tactics for food manipulation in a species difficult to observe in the wild or maintain in captivity.  相似文献   

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