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1.
《Journal of Natural History》2012,46(32):2987-2996
Glyphochaeta laudieni, a new genus and species of the “Spionidae”, is described from the Arctic. The specimens were collected from the Kongsfjorden, Spitsbergen, Svalbard, in a marine grotto. Glyphochaeta laudieni was associated with colonies of unidentified Bryozoa. This new genus and species is characterized by a prostomium with frontal horns, the absence of branchiae and sabre chaetae, and the presence of grooved spines which replace hooded hooks in some chaetigers of the middle body region. These spines are associated with glandular organs situated in neuropodia. The significance of characters for determining the systematic position of Glyphochaeta within “Spionidae” is discussed. Glyphochaeta laudieni is probably related to Pygospio elegans.  相似文献   

2.
《Journal of Natural History》2012,46(43-44):2723-2763
The caenogastropod proboscis is a complex morphological adaptation to a carnivorous diet. This comparative morphological investigation of proboscis and snout anatomy in Caenogastropoda shows that there is undescribed diversity in both snout/proboscis wall composition and introversion/retraction musculature. There is morphological evidence which suggests that a proboscis evolved separately in at least four separate caenogastropod groups, each characterized by the presence of novel retractor muscles and different modifications of plesiomorphic “aortic muscles”. The biomechanical operation of the proboscis and snout utilizes a hydrostatic skeleton, but several higher caenogastropods have evolved a complex muscular hydrostat in the snout/proboscis wall which may mitigate the need to isolate the proboscis haemocoel during proboscis eversion.  相似文献   

3.
《Journal of Natural History》2012,46(6):1269-1279
A new genus of ascothoracid, Bifurgaster gen. nov., has been found parasitizing brisingid asteroids Freyella spp. The genus comprises two species, B. freyellae sp. nov. and B. kermadeca sp. nov., from the north-east Atlantic Ocean and south Pacific Ocean respectively, at depths of over 4000 m. The genus is characterized by the adult female having a bilobed mantle within which is a reduced main body with little or no segmentation. The only appendages are the first antennae and second maxillae. Each lobe of the mantle contains two branches of the gut and ovary and a distinctive gland. Males and larvae of B. freyellae are described. The genus is placed in the family Dendrogastridae, and is thought to be intermediate between Ulophysema and Dendrogaster.  相似文献   

4.
《Journal of Natural History》2012,46(13-14):813-825
The viviparous New World Mabuya (Reptilia, Scincidae) are characterized by a peculiar suite of reproductive traits associated with an extreme degree of matrotrophy and a specialized placenta. We gathered information on female reproductive traits of South American Mabuya based on a compilation of literature data plus original information on two species (Mabuya dorsivittata and Mabuya macrorhyncha). Considering brood size, we identified one “large-brooded” group (brood sizes up to eight to ten) and one “small-brooded” group (brood sizes up to four to six). Brood size tended to be positively correlated with female body size among species, although the correlation is not as strong as it is within species. There were some general trends for the reproductive ecology of New World Mabuya, such as early sexual maturation, brood sizes of usually four to six young, and parturition occurring around the dry–wet season transition.  相似文献   

5.
《Journal of Natural History》2012,46(41-44):2741-2755
A new species of the tardigrade genus Macrobiotus is described. The species, designated M. ciprianoi n. sp., was isolated from a mixture of Provence broom leaf litter and mosses, and from rock mosses collected in the Sierra de Guadarrama, Madrid (Spain). Given that Macrobiotus ciprianoi n. sp. shares several characters to members of the “tenuis group”, we assessed the taxonomic homogeneity of the group. The new species differs from those of the “tenuis group” according to a unique set of characters related with claw shape, features of the buccal‐pharyngeal apparatus, and egg morphology. Our analysis of holotypes and/or paratypes of “tenuis group” species and other Macrobiotus species with similar characters (M. bondavallii and M. caelicola) reflects the heterogeneity of this group of species as currently described.  相似文献   

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《Journal of Natural History》2012,46(1-2):101-105
Post‐mounting courtship behaviour of a 6–8 mm long scatophagid fly Hydromyza livens which lays its eggs in yellow water lily (Nuphar lutea) is described and analysed. Enigmatic male–male encounters are described, along with lengthy “homosexual” mounting behaviour. A possible interpretation of both types of behaviour is given, with reference to their adaptive significance and the special problems encountered by males in locating females.  相似文献   

9.
《Journal of Natural History》2012,46(42):3633-3647
The muscular anatomy and fine structure of the haptor of a monogenean, Capsala sp., together with an observational distribution study, are described from specimens collected from the dorsolateral and ventral surfaces of the blue marlin, Makaira nigricans. The haptor is composed of seven loculi, which are arranged around a central pair of accessory sclerites. Marginal hooklets and hamuli were not observed. The presence of an outline left by the haptor on the host's skin and the lack of evidence of an adhesive secretion suggested that the haptor attaches primarily by suction. Tendons originating in the extrinsic peduncle muscles insert, via a proximal notch in the accessory sclerites, into the basal tegumental lamina on the ventral surface of the haptor. On contraction the centre of the haptor is thought to be drawn upwards both directly by the extrinsic tendons in the haptoral wall but also by the accessory sclerites which are brought into a vertical position. This increases the volume beneath the haptor, consequently reducing the pressure and thus producing suction. The ribbed marginal valve prevents the inward movement of water. Intrinsic circular and radial muscles in the haptoral wall are also thought to produce suction by drawing the haptoral wall inwards, again increasing the volume beneath and causing a pressure reduction. It is suggested that interconnecting fibres observed between the intrinsic muscles may store elastic energy, allowing Capsala sp. to maintain suction attachment without having constantly to contract its muscles. Papillae on the inner ( = ventral) surface of the haptor are suggested to aid attachment by firstly spreading the negative pressure over the inner surface of the haptor and, secondly, through resisting the shear forces encountered as the fish swims. Both functions are achieved by increasing the surface area of contact with the host's skin, and therefore the frictional forces. Theoretical estimates of the suction efficiency indicate that suction is double the maximum theoretical drag forces which would be experienced by Capsala sp. when M. nigricans is swimming at speeds of both 1 and 20 m s?1 and suggests that suctorial attachment is efficient. The distribution of Capsala sp. is not thought to be restricted by the surface topography of the host, demonstrated by the fact that individuals were located in both the roughest and smoothest areas of the marlin's skin surface. Distribution is therefore thought to be influenced by other factors such as hydrodynamics, nutritional value of the attachment site, immunological restrictions or cross‐fertilization between parasites.  相似文献   

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The revision of the saproxylic hoverflies collected in Serbia from 1950 to 2010 has revealed a total of 56 species, of which Sphiximorpha subsessilis (Illiger in Rossi) is new to the Balkan Peninsula and Arctophila superbiens (Muller), Blera fallax (Linnaeus), Brachyopa panzeri Goffe, Brachyopa testacea (Fallén), Brachyopa vittata Zetterstedt and Chalcosyrphus piger (Fabricius) are new to Serbia. According to “Syrph the Net, the database of European Syrphidae”, 16 of the 56 species are threatened with extinction in Europe, while 6 species are “strictly protected” and 13 are “protected” under Serbian legislation. Distribution maps for each species, as well as new data on adult habitats, are provided. The conservation status of the saproxylic hoverflies of Serbia is discussed. The present study attempts to provide a basis for the conservation of the saproxylic hoverflies of this Balkan country.  相似文献   

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《Journal of Natural History》2012,46(5-6):265-272
Species of the genus Mesothuria (fam. Synallactidae) occurring in the Atlantic Ocean are revised. The genus includes 25 valid species, nine of them known from the Atlantic. The new species Mesothuria milleri sp. nov. is described from the north-east Atlantic. It is argued that the genus Zygothuria, established by Perrier in 1898 and recognized later only by Deichmann, should be maintained as a separate genus. Mesothuria and Zygothuria differ in body form, arrangement of ambulacral appendages, and structure of segments of calcareous ring and ossicles from the body wall. The six known species of Zygothuria are reviewed. Zygothuria oxysclera, a former variation of Zygothuria lactea, is proposed as a valid species. Identification keys to species of the genus Zygothuria and Atlantic species of the genus Mesothuria are provided. Data on the life history and reproductive biology of Mesothuria milleri and Zygothuria lactea are given. Both species are common in the north-east Atlantic.  相似文献   

14.
Stenolemus bituberus is an araneophagic “assassin bug” (Heteroptera; Reduviidae; Emesinae) that typically is found living in spider webs. We documented the life history of S. bituberus in the field for 13 months, determining its developmental phenology and microhabitat characteristics as well as describing its mating and predatory behaviour. We also included a morphometric analysis of the instars. Our study revealed that S. bituberus is univoltine with five juvenile instars. Although S. bituberus is found in the webs of spiders from a wide range of genera, it is found most commonly in the webs of Achaearanea, Badumna, Pholcus, and Stiphidion. Multiple juveniles often were found on a single web, but adults tended to be more solitary. Stenolemus bituberus appears to have two distinct hunting strategies: “stalking”, in which they slowly approach the spider, make contact and then strike; and “luring”, in which they attract the spider within range by manipulating the silk with their legs.  相似文献   

15.
Abstract

The new genus Homalacanthus is proposed for “Acanthodescocinnus and “Acanthodesaffinis of Whiteaves. Diplacanthus horridus Woodward is redescribed.  相似文献   

16.
Third-stage larvae of two species of the genus Anisakis, A. simplex (Rudolphi, 1809) and A. physeteris Baylis, 1923, and those of two types of Lappetascaris sp. are described from four species of squids from the central and western North Pacific Ocean. Larvae of Lappetascaris sp. Type A were 15-33 mm long and occurred individually free in the mantle musculature of squids, whereas those of Lappetascaris sp. Type B were considerably smaller, only 3–7 mm long, and were found in capsules on the stomach wall, each capsule containing up to 50–60 larvae. It is not known whether both larval types are conspecific or belong to two different Lappetascaris species. Anisakis simplex and A. physeteris larvae were found in Onychoteuthis borealijaponica Okada and Gonatopsis borealis Sasaki, and O. borealijaponica, respectively, whereas Lappetascaris sp. Type A and Type B larvae from Thysanoteuthis rhombus Troschel, Ommastrephes bartramii (LeSueur), Onychoteuthis borealijaponica and G. borealis, and O. bartramii, respectively. The findings represent several new host records and all these parasites are reported for the first time from squids in the central North Pacific Ocean.  相似文献   

17.
《Journal of Natural History》2012,46(15-16):969-992
A remarkable new species of black fungus gnat Pnyxiopalpus roslii sp. nov., was discovered from nests of the termite Nasutitermes proatripennis in Ulu Gombak, Malaysia, and is described based on the female morphology and DNA barcodes. This is the first record of a termitophilous black fungus gnat from South-east Asia. The new species is easily distinguished from its known congeners by the degeneration of all thoracic setae into tiny setulae. This species is described as a symbiont of the host termite based on field observations and the examination of specimens. The “wing stump” structure of the new species indicates that this species has wings after eclosion and later loses them, an adaptation to a cryptic life. A second still undescribed termitophilous species of Pnyxiopalpus was observed walking in a marching column of the termite Longipeditermes longipes in Ulu Gombak.  相似文献   

18.
《Journal of Natural History》2012,46(47-48):2935-2959
The caecilian Ichthyophis longicephalus was described in 1986 based on a single specimen. Only one specimen has been referred subsequently to this species, and the validity of that referral has been questioned. Seven specimens discovered in 2009–2010 at two new localities and two specimens collected in 1990 from a third locality are referred here to I. longicephalus. These specimens are described and compared with the poorly preserved holotype. Mitochondrial DNA data are consistent with the interpretation that the new specimens represent a single species distinct from (and most closely related to I. tricolor among) sampled congeners. The previously referred specimen, from c. 320 km south of the type locality, is not I. longicephalus and probably represents an undescribed species. The “rediscovery” of I. longicephalus in forests and disturbed habitats indicates that the species probably could be transferred from the Data Deficient to the Least Concern category of the IUCN Red List.  相似文献   

19.
A total of 36 syllid specimens preserved on permanent slides, which were collected and identified by G. Cognetti, and deposited at the Museum of the Stazione Zoologica “Anton Dohrn” in Naples, Italy, were re‐examined. Among the material, two new species of Autolytus, Autolytus antondohrni sp. nov. and A. cognettii sp. nov., were found and are described. Three new combinations are assigned: Autolytus mediterraneus (Cognetti, 1953), Exogone (Parexogone) meridionalis (Cognetti, ) and Syllis alternata Moore, 1908. Four lectotypes are designated for Autolytus convolutus Cognetti, 1953, A. mediterraneus (Cognetti, 1953), A. neapolitanus Cognetti, 1953 and Exogone (Parexogone) meridionalis (Cognetti, ). Proceraea scapularis (Claparède, ) is resurrected.  相似文献   

20.
《Journal of Natural History》2012,46(45-46):2825-2863
Leptodora kindtii is a peculiar carnivorous crustacean widely distributed and occupying a prominent position in the freshwater planktonic communities. This species was originally found and described in the 1840–1860s and since then it has been a subject of numerous studies, morphological, embryological, behavioural, and ecological, which elucidated various aspects of its body structure and mode of life. Nevertheless, analysis of the literature and personal investigation of material on the species have led to the conclusion that the morphology of the species was not studied properly and the previous data might be incorrect and inconsistent, which obstructed proper understanding of its phylogeny, taxonomic position, and habits. In the present investigation, the external morphology of L. kindtii is described and analysed in detail, from comparative morphological and eco‐morphological aspects. Also, the morphological features of representatives of the species from different populations over the vast area of its Eurasian range have been studied with respect to their intra‐ and interpopulational variability and taxonomic significance. It has been shown that the majority of populations of L. kindtii from Europe to the Far East of Russia do not display any significant morphological differences, which testifies to their conspecificity. Only a small set of adult specimens from Lake Bolon (the Amur River basin, Far East of Russia) differed considerably from others in their small size and body proportions which implies the occurrence of another species of the genus in this region to be studied and validated in the future together with the enigmatic cave species L. pellucida Josef. In spite of high morphological peculiarity, L. kindtii possesses a number of “core” characteristics, which undoubtedly show its close relationship with other mostly small branchiopods (Ctenopoda, Anomopoda, Onychopoda) traditionally united in the taxon Cladocera whose validity has also been supported by modern molecular‐genetic studies.  相似文献   

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