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1.
A new species in the little-known digenean fauna of Paraguayan birds is described in detail, especially in relation to its terminal genitalia. The new form, Megalophallus deblocki n. sp., is a microphallid from the intestine of the snail kite Rostrhamus sociabilis (Vieillot). It is differentiated in detail from its congeners, but differs mainly in having a substantially larger phallus (e.g. in relation to the ventral sucker), a smaller ventral sucker and smaller eggs. Comments are included on the functional morphology of the terminal genitalia.  相似文献   

2.
The delimitation of species boundaries, particularly those obscured by reticulation, is a critical step in contemporary biodiversity assessment. It is especially relevant for conservation and management of indigenous fishes in western North America, represented herein by two species with dissimilar life histories codistributed in the highly modified Colorado River (i.e., flannelmouth sucker, Catostomus latipinnis; bluehead sucker, C. (Pantosteus) discobolus). To quantify phylogenomic patterns and examine proposed taxonomic revisions, we first employed double‐digest restriction site‐associated DNA sequencing (ddRAD), yielding 39,755 unlinked SNPs across 139 samples. These were subsequently evaluated with multiple analytical approaches and by contrasting life history data. Three phylogenetic methods and a Bayesian assignment test highlighted similar phylogenomic patterns in each, but with considerable difference in presumed times of divergence. Three lineages were detected in bluehead sucker, supporting elevation of C. (P.) virescens to species status and recognizing C. (P.) discobolus yarrowi (Zuni bluehead sucker) as a discrete entity. Admixture in the latter necessitated a reevaluation of its contemporary and historic distributions, underscoring how biodiversity identification can be confounded by complex evolutionary histories. In addition, we defined three separate flannelmouth sucker lineages as ESUs (evolutionarily significant units), given limited phenotypic and genetic differentiation, contemporary isolation, and lack of concordance (per the genealogical concordance component of the phylogenetic species concept). Introgression was diagnosed in both species, with the Little Colorado and Virgin rivers in particular. Our diagnostic methods, and the agreement of our SNPs with previous morphological, enzymatic, and mitochondrial work, allowed us to partition complex evolutionary histories into requisite components, such as isolation versus secondary contact.  相似文献   

3.
Acanthotrema felis n. sp. (Digenea: Heterophyidae) is described from adult flukes recovered in the small intestine of stray cats caught in the southwestern part of the Republic of Korea. The worms were characterized by minute body size, the presence of a bipartite seminal vesicle, and a ventral sucker associated with a ventrogenital sac, which enclosed 3 sclerites (2 long and pointed, and I short and thumblike), and an unarmed gonotyl. They were assigned to Acanthotrema Travassos, 1928, which currently contains 4 species. The new species resembles A. acanthotrema, the type species, because both have 3 sclerites on the ventrogenital sac. However, all 3 sclerites in the new species are armed with minute spines on their base, whereas only 2 sclerites in A. acanthotrema have minute spines near their tips. Three species of Stictodora Looss, 1899, namely,Stictodora tridactyla Martin and Kuntz, 1955, S. cursitans Kinsella and Heard, 1974, and S. tanayensis Velasquez, 1973, are transferred to Acanthotrema, and the new species is distinguished from them particularly in terms of the number and shape of its sclerites. The generic diagnosis of Acanthotrema is emended.  相似文献   

4.
Salsuginus neotropicalis n. sp. is described from the gills of Belonesox belizanus (Kner), the pike killifish (Poeciliidae), from the southeastern Mexico. S. neotropicalis is distinguished from all other congeners by the morphology of the haptoral sclerites, especially by the presence of a ventral bar with notably enlarged ends, and by possessing overlapping gonads. The diagnosis of Salsuginus is amended based on the position of gonads in this species. This is the first known Salsuginus species occurring in a freshwater fish from the Neotropical Region.  相似文献   

5.
Rohde  K.  Heap  M.  Hayward  C. J.  Graham  K. J. 《Systematic parasitology》1992,21(1):69-79

Calicotyle australiensis n. sp. from Chimaera sp., caught off the coast of New South Wales, is described. It differs from the other species of the genus in the combination of the following characteristics: length of the penis-tube, absence of medial diverticula of the caeca and presence of hamuli. Calicotyle sp. from Rhinochimaera pacifica and Rugogaster hydrolagi from Chimaera sp. caught at the same locality are reported and illustrated.

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6.
Gorgoderina festoni n. sp. is described from the urinary bladder of Gastrophryne usta, Leptodactylus labialis, L. melanonotus and Bufo marinus from localities at low altitude in the states of Veracruz, Oaxaca, Guerrero and Colima, Mexico. This species differs from most other species of the genus by a combination of the following characters: lobed vitelline masses, body size 3.45–4.26 (mean 3.75) mm and sucker-ratio 1:1.3–1.52 (mean 1:1.44). The new species shares these three features with G. bilobata Rankin, 1937, G. schistorchis Steelman, 1938, G. tenua Rankin, 1937, G. vitelliloba (Olsson, 1876) and G. cryptorchis Travassos, 1924, but it differs from the first four in having gonads with entire margins. G. festoni most closely resembles G. cryptorchis, but differs from this species in body width at the level of the ventral sucker and in the absence of oesophageal glands. The autapomorphy that distinguishes G. festoni from all other members of the genus is the presence of a tegumental extension (festoon) on the external margin of the ventral sucker.  相似文献   

7.
A new digenean, Allassogonoporus callosciuri n. sp. from the plantain squirrel Callosciurus notatus from the Malaysian state of Sarawak, Borneo, is described. The new species differs from: A. amphoraeformis by the size of the ventral sucker and the position of the vitellarium and uterus; and from A. marginalis by the smaller oral sucker, the position of the testes and vitellarium; from A. vespertilionis by the position of the vitellarium, testes and ovary; from A. asymmetrica by the position of the testes and uterus. Gilford's (1955) and Dubois' (1963) opinions on the synonymy of Allassogonoporus and Myotitrema is supported. No representatives of the family Allassogonoporidae have been reported previously from sciurids or South-East Asia.  相似文献   

8.
Calicotyle australiensis n. sp. from Chimaera sp., caught off the coast of New South Wales, is described. It differs from the other species of the genus in the combination of the following characteristics: length of the penis-tube, absence of medial diverticula of the caeca and presence of hamuli. Calicotyle sp. from Rhinochimaera pacifica and Rugogaster hydrolagi from Chimaera sp. caught at the same locality are reported and illustrated.  相似文献   

9.
The musculature of male genitalia was studied hitherto only in two species of Tephritidae, one species of Platystomatidae, one species of Pallopteridae, and three species of Ulidiidae of the superfamily Tephritoidea. The split of the hypandrium from one structure into three (the hypandrium and two lateral sclerites) is traced. The hypandrial origin of the lateral sclerites of the hypandrial complex is shown based on the localization of muscle attachment sites. The subepandrial origin of the inner lobes of the surstyli is also confirmed.  相似文献   

10.
11.
Alcyonacean octocorals in tropical reefs are usually not considered as reef builders. Some Sinularia species, however, are capable of consolidating sclerites at the colony base to form spiculite. Nanwan Bay, southern Taiwan, features both fossilized and recently formed boulders composed of spiculite, thus demonstrating the role of Sinularia in contributing to the reef structure. Section radiography of an 18.5 kg spiculite boulder demonstrated a regular density banding of 3–6-mm intervals. Core survey indicated spiculite coverage of 25–30% on the live reef and of 30–40% on the uplifted boulders. Cores taken from living Sinularia revealed a distinct transition from discrete sclerites to compact spiculite and amorphous calcium carbonate cementing the sclerites. In the widespread S. gibberosa, sclerite formation appeared to start intracellularly, followed by a prolonged extracellular calcification process. At the calcification site, multiple sclerocytes formed expanded pseudopod-like membranes that interconnected, forming multicellular vesicles (MCVs) around the sclerites. The MCVs and the pseudopods disappeared at sclerite maturation, followed by degradation of the sclerocytes around the mature sclerites. At the colony base, granular vesicles were distributed among the sclerites, indicating a cementing process in progress. These findings suggest that colonies of Sinularia are able to cement sclerites and consolidate them at their base into spiculite, thus making them reef builders.  相似文献   

12.
Two species of the Zoogonidae are recorded from Heron Island on the southern Great Barrier Reef. Steganoderma (Lecithostaphylus) gibsoni n. sp. is described from the intestine of Abudefduf whitleyi (Pomacentridae). The new species is distinguished by the combination of the following: pedunculate ventral sucker, caeca extending well past testes, presence of two-chambered internal seminal vesicle, vitelline follicles extending only to anterior margin of testes, and testes close to ventral sucker. Zoogonus pagrosomi Yamaguti, 1939 is recorded from Lethrinus atkinsoni (Lethrinidae). This species has been recorded previously only from a sparid from Japan. A new combination, Steganoderma (Lecithostaphylus) fugus (Zhang, Qiu & Li, 1986), is made.  相似文献   

13.
Two known and two new species of Diplectanocotyla Yamaguti, 1953 (D. gracilis Yamaguti, 1953, D. megalopis Rakotofiringa & Oliver, 1987, D. langkawiensis n. sp. and D. parva n. sp.) were collected from Megalops cyprinoides (Megalopidae) off Langkawi, Kedah and Matang, Perak, Peninsular Malaysia. All four species possess similar types of sclerotised male and female reproductive structures and similar soft anatomical features. The squamodisc sclerites of all four species have spine-like projections with varying degrees of visibility and shapes (sharp-pointed to triangular). In D. megalopis and D. langkawiensis n. sp. the spines are sharp-pointed and distinct on sclerites from rows 5–6 onwards. In D. gracilis and D. parva n. sp. the sclerite spines are triangular, lightly sclerotised and occur on almost all of the sclerites. D. parva n. sp. has comparatively the smallest set of anchors, bars, squamodiscs and squamodisc suckers. The anchors and bars of the other three species are almost similar in overall size, and the main distinguishing feature is the relative lengths of the inner and outer roots of the ventral anchors. In D. gracilis the outer root is very much smaller than the inner root and they are disposed almost at a right angle to each other. In D. megalopis the outer root is usually about half the length of the inner root and the roots are inclined at c.60° to each other. In D. langkawiensis n. sp. the roots are inclined at c.40° degrees and the outer root is of a similar length or only slightly shorter than the inner root. The openings of the two squamodisc suckers of all four Diplectanocotyla species are surrounded by tiny scale-like spines. Bifid tegumental spines are found in the posterior region of all four species, differing only in their extent: in D. parva n. sp. the tegumental spines are only distributed in the peduncular region and not beyond, whilst in the other three species the tegumental spines extend from the posterior level of the testis to the end of the peduncle. An amended diagnosis of Diplectanocotyla and a key to its species are appended.  相似文献   

14.

A new cryptogonimid trematode, Siphoderina hustoni n. sp., is reported, collected off Lizard Island, Queensland, Australia, from the Maori snapper Lutjanus rivulatus (Cuvier). The new species is moderately distinctive within the genus. It is larger and more elongate than most other species of Siphoderina Manter, 1934, has the shortest forebody of any, a relatively large ventral sucker, a long post-testicular zone, and is perhaps most recognisable for the substantial space in the midbody between the ventral sucker and ovary devoid of uterine coils and vitelline follicles, the former being restricted to largely posterior to the ovary and the latter distributed from the level of the anterior testis to the level of the ovary. In phylogenetic analyses of 28S ribosomal DNA, the new species resolved with the other nine species of Siphoderina for which sequence data are available, all of which are from Queensland waters and from lutjanid and haemulid fishes. Molecular barcode data were also generated, for the ITS2 ribosomal DNA and cox1 mitochondrial DNA markers. The new species is the first cryptogonimid known from L. rivulatus and the first metazoan parasite reported from that fish in Australian waters.

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15.
A new species of Steganoderma (Steganoderma) (Digenea: Zoogonidae) was found in the digestive tract of the southernmost, endemic and scale-less characid, Gymnocharacinus bergi, inhabiting thermal headwaters of the Valcheta Creek in northern Patagonia, Argentina. Steganoderma valchetensis n. sp. is included in the subgenus Steganoderma because of having a sessile ventral sucker and caeca reaching to the testes. This new species can be distinguished from other species of this genus on the basis of body-length, sucker-ratio, the length of the cirrus-sac, the morphology of the seminal vesicle and gonads, and the location of the vitelline follicles and genital pore. The taxonomic status of the species of Steganoderma, parasitising the freshwater fishes of Patagonia, in southern Argentina, and Chile, is also discussed.  相似文献   

16.
An opecoelid digenean, Dactylomyza gibsoni n. g., n. sp. is described and figured from Schuettea woodwardi (Waite), a monodactylid from off the coast of Western Australia. The new genus conforms to the concept of the opecoelid subfamily Opecoelinae. The resemblance of the new genus to three other opecoelid genera, Pseudopecoeloides Yamaguti, 1940, Opecoeloides Odhner, 1928 and Poracanthium Dollfus, 1948, is discussed. Dactylomyza n. g. is distinguished from these morphologically similar worms on the basis of its median genital pore, ventral sucker appendages, uroproct and the absence of an accessory sucker. Pseudopecoeloides equesi Manter, 1947 is transferred to the new genus as Dactylomyza equesi (Manter, 1947) n. comb.  相似文献   

17.
Three species of the bunocotyline genus Saturnius Manter, 1969 are described from the stomach lining of mugilid fishes of the Mediterranean and Black Seas. Two of the species are new: S. minutus n. sp. occurs in Mugil cephalus off the Mediterranean coast of Spain; and S. dimitrovi n. sp., a parasite of M. cephalus off the Bulgarian Black Sea coast and the Spanish Mediterranean coast, was originally described as S. papernai by Dimitrov et al. (1998). In addition, S. papernai Overstreet, 1977 is redescribed from M. cephalus off the Spanish Mediterranean coast and from Liza aurata and L. saliens off the Bulgarian Black Sea coast. The three species are distinguished morphometrically using univariate and multivariate analyses. These results were verified using Linear Discriminant Analysis which correctly allocated all specimens to their species designations based on morphology (i.e. 100% successful classification rate) and assigned almost all specimens to the correct population (locality). The following variables were selected for optimal separation between samples: the length of the forebody, ventral sucker and posterior testis, the length and width of the posteriormost pseudosegment, and the width of the muscular flange at ventral sucker level.  相似文献   

18.
Chancelloriids are a group of enigmatic sessile animals that are covered with sclerites shaped as rosettes of spines, producing an appearance like that of a barrel cactus. They are known only from Cambrian rocks. Isolated sclerites of chancelloriids are widespread in small shelly faunas, but they have proven difficult to treat taxonomically due to the variation within and between individual animals. We report on large samples of chancelloriid sclerites from the Meishucunian (pre‐trilobitic Lower Cambrian) of eastern Yunnan Province, China, including material from the Dahai Member of the Zhujiaqing Formation (the Zhujiaqing section, Dahai, Huize County) and the Shiyantou Formation (the Xiaotan section, Yongshan County). The material from the Dahai Member appears to come from a single species, Chancelloriella irregularis. Statistical analysis of morphotype co‐occurrences in different samples suggests that several species are represented in the material from the Shiyantou Formation, which we herein tentatively place in four species, Allonnia erromenosa, Allonnia tetrathallis, Archiasterella charma sp. nov. and Archiasterella cf. pentactina. We suggest therefore that careful study of large collections of isolated chancelloriid sclerites permits the identification of different species, opening the possibility of their use in evolutionary or stratigraphical studies. In particular, in South China, it seems that Chancelloriella irregularis is characteristic of rocks of the Paragloborilus subglobosusPurella squamulosa Assemblage Zone and the Watsonella crosbyi Assemblage Zone, whilst Archiasterella and Allonnia first appear in the overlying Sinosachites flabelliformisTannuolina zhangwentangi Assemblage Zone. C. irregularis is thus amongst the oldest well‐characterized chancelloriids, and the irregularity and poor organization of its sclerites relative to those of younger forms support the hypothesis that chancelloriid sclerites are compound structures arising from the fusion of originally separate elements, perhaps homologous with sclerites of halkieriids and other coeloscleritophorans. The similarity between the arrangement of rays in a chancelloriid sclerite and the arrangement of bubbles in small bubble clusters suggests that in many cases, aspects of the form of chancelloriid sclerites are the result of simple physical processes.  相似文献   

19.
The understanding of how environmental factors and agricultural practices affect population dynamics of insect pests is necessary for pest management. Here, we provide insight into the ecology of the banana rind thrips Elixothrips brevisetis (Bagnall) (Thysanoptera: Thripidae) by collecting and analysing a spatiotemporal database of population estimates in Martinique (West French Indies). We assessed the influence of climatic variables (which were rainfall and temperature) and biotic variables (which were banana and three weed species) on the adult thrips abundance for different components of the banana plant (sucker, mother plant and bunch) and evaluated the effect of thrips abundance and standard bunch covers on damages. The abundance of thrips on the sucker, the mother plant, and the bunch was significantly related to the abundance on neighbouring banana plants, and spatial autocorrelation indicated that E. brevisetis dispersed for only short distances. The number of thrips on the mother plant and on the bunch was positively related to the number of thrips on the sucker, suggesting that the thrips may disperse from the sucker to the mother plant and then to the bunch. The abundance of thrips on the sucker increased with sucker height and was positively correlated with the mean daily rainfall during the 17 days before sampling; the length of that period might correspond with the time required for an individual to complete its life cycle. Covered bunches had 98% fewer thrips than non‐covered bunches, and the damage caused by thrips was linearly related to the number of thrips present between the 2nd and 4th week after flowering. Finally, we found that the presence of Alocasia cucullata, Dieffenbachia seguine and Peperomia pellucida is significantly related with a decrease in thrips abundance on banana plants, suggesting the use of these weeds as potential trap plants.  相似文献   

20.
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