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1.
Higashi R  Tsukagoshi A 《ZooKeys》2012,(193):27-48
Two new species of the interstitial ostracod genus Parvocythere, Parvocythere gottwaldisp. n. and Parvocythere gracilissp. n., are herein described. Although these two new species are clearly distinguishable by certain morphological differences in elements of the male copulatory organ, and the carapace, they share the following simplified characters of the appendages and male copulatory organ: antennular fourth podomere with no suture; reduced claws on the distal end of antenna; and asymmetric male copulatory organ. The morphological differences among known and new Parvocythere species suggest that the species of this genus can be classified into two groups by the presence/absence of the suture on the antennular fourth podomere. The "Group S" is characterised by the presence of the antennular suture, and all species of this group have a two-clawed antenna and symmetric male copulatory organ, characters which are generally seen in cytheroid ostracods. The species belonging to "Group N" are characterised by the absence of the suture, regarded as a pedomorphic character, show the following characters: two clawed or one clawed antenna, and symmetric or asymmetric male copulatory organ. The morphological variation within Group N includes reductive characters regarded as an adaptation to the narrow spaces of the interstitial environment of a sandy beach. These intrageneric morphological variations of the exclusively interstitial genus Parvocythere suggest the possibilities that Group N might be derived from Group S, and that some adaptive characters to an interstitial environment could have developed after the colonisation of these environments.  相似文献   

2.
Two new species of microcotylid monogeneans are described. Solostamenides platyorchis n. sp. was obtained from the gills of Mugil cephalus (Mugilidae) and Polylabroides guangdongensis n. sp. from the gills of Sparus macrocephalus, S. berda and Acanthopagrus latus (Sparidae). Solostamenides platyorchis is morphologically similar to S. mugilis (Vogt, 1878) Unnithan, 1971 and S. pseudomugilis (Hargis, 1956) Unnithan, 1971 in the structure of the copulatory organ, but differs from them in the number, arrangement and shape of the testes. Features of P. guangdongensis distinguishing it from other species of the genus include a copulatory organ lacking small spines and an extremely long polar filament on the egg. In view of this species, we suggest omitting the presence of small spines on the copulatory organ as a diagnostic character of the genus Polylabroides Mamaev & Parukhin, 1976.  相似文献   

3.
Heterocotyle pastinacae Scott, 1904 is redescribed and a neotype is designated. H. pastinacae is most easily distinguished from other members of the genus by the elaborate arrangement of sclerotised spines in the vagina. The male copulatory organ also serves to differentiate it from other species in the genus. A possible function for the vaginal spines and unique form of the male copulatory organ is discussed. The use of head organ number as a generic character is considered questionable.  相似文献   

4.
Knowledge of the cosmopolitan land planarian Bipalium kewense is briefly reviewed. A neotype and paraneotypes are designated. External morphology and internal anatomy of the species are redescribed. Karyological studies on B. kewense reveal a diploid chromosome complement of 16; one subtelocentric, three submetacentric and four metacentric chromosome pairs. Taxonomy of B. kewense is revised and full synonomy provided. New synonomies include Placocephalus isabellinus Geba and Bipalium costaricensis Hyman. Species that phenetically resemble B. kewense are divided into three groups primarily on the basis of stripe pattern and cutaneous musculature. A differential diagnosis distinguishing B. kewense from taxa in these groups is provided. Present distribution of the species is mapped. New records are reported from Barbados, Colombia, Costa-Rica, El Salvador, Indonesia, Madagascar, Malaysia, Mauritius, Mexico, Puerto Rico, Tahiti, Taiwan and Zimbabwe. Worldwide B. kewense exhibits a disjunct distribution pattern. In Australia and in the United States a similar pattern of occurrence is evident. The species appears to be dispersed with rooted plants. The natural range of B. kewense extends from Vietnam to Kampuchea, possibly extending to Malaysia. Elsewhere it has been introduced by man. The bipaliid fauna of Vietnam, to which B. kewense belongs, appears to have closer phenetic affinities with the faunas of adjacent southern rather than northern regions.  相似文献   

5.
外群选择对隧蜂科(膜翅目:蜜蜂总科)系统重建的影响   总被引:1,自引:0,他引:1  
外群用于给树附根和推断祖先性状状态。通常,来自内群的姐妹群中的多个分类单元被共同选择作为外群。为了在经验上验证这一方法, 我们采用了3种外群选择策略: 姐妹群中的单一分类单元, 姐妹群中的多个分类单元和连续姐妹群中的多个分类单元。以隧蜂科(膜翅目: 蜜蜂总科)的系统发育重建为例, 我们评估了这3种策略对树拓扑结构的影响, 包括最大似然树、 最大简约树和贝叶斯树。初步结果表明: 相比其他两种策略, 采用姐妹群中的多个分类单元作为外群更有利于系统发育重建得到现已被广泛认可的隧蜂科系统发育关系; 相比最大似然法和贝叶斯法, 虽然隧蜂科系统发育关系没有被很好地解决, 但最大简约法在不同外群选择策略下得到了较为一致的拓扑结构  相似文献   

6.
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8.
A study of monogenean gill parasites from three species of the genus Clarias Scopoli, 1777 (Clariidae), namely Clarias camerunensis L?nnberg, 1895, C. jaensis Boulenger, 1909 and C. pachynema Boulenger, 1903, from the Nyong Basin (Cameroon) revealed the presence of three new monogenean species of the new genus Birgiellus, namely Birgiellus mutatus n. sp. from C. pachynema, B. calaris n. sp. from C. jaensis and B. kellensis n. sp. from C. camerunensis. The genus Birgiellus differs from the genus Quadriacanthus by the morphology of the ventral bar composed of a single piece (two distinct in Quadriacanthus) and the size of the uncinuli IV, which are not much different from the others (longest in Quadriacanthus). Birgiellus calaris differs from B. mutatus by its ventral anchors longer and larger, the morphology of the ventral bar with a short incision between the two branches, and a long and trapezoid handle, the size of the sclerotised structures of the male and female copulatory organs, the larger thickness of the hook in the male accessory piece, the latter having also a heel. Birgiellus kellensis is closer to B. calaris but can be distinguished by the small size of its dorsal and ventral anchors, its transverse bars, male copulatory organ, and the accessory piece, which also has not a heel but a secondary blade. According to the clause 8.5.2 of the International Zoological Code of Nomenclature (1999) the genus Birgiellus and the species B. mutatus and B. calaris, respectively, replace Claridectes, C. clarisa and C. alacris previously described by Birgi (1987), but whose specimens were not deposited in a museum. All the three taxa described exhibit a strict (oioxenous) host specificity.  相似文献   

9.
Eight new species of Ligophorus Euzet &; Suriano, 1977 (Monogenea: Ancyrocephalidae) are described from two species of mullets from the Red Sea. Ligophorus bykhowskyi n. sp. and L. zhangi n. sp. from Crenimugil crenilabris (Forsskål) differ from other species of the genus in the structure of the male copulatory organ, which has a simple accessory piece and a wide copulatory tube that arises from a large, single-chambered, expanded base. Ligophorus simpliciformis n. sp., L. bipartitus n. sp., L. campanulatus n. sp., L. mamaevi n. sp., L. lebedevi n. sp. and L. surianoae n. sp. from Liza carinata (Valenciennes) are differentiated on the basis of the morphometrics of the hard parts of the haptor and male copulatory organ. The eight species represent the first records of species directly attributed to Ligophorus from the Red Sea. Measurements of the haptoral hard-parts and the male copulatory organ of the new species are analysed with the aid of Principal Component Analysis. Three morphological types of male copulatory organ, five types of anchor, and two types of ventral and three types of dorsal bars were distinguished among these species. L. bykhowskyi and L. zhangi from C. crenilabris have the same type of male copulatory organ and anchors. Those species from Liza carinata have only one common morphological character, a thick copulatory tube, but have two types of accessory piece, four types of anchors and three types of bars. All species of Ligophorus found on mullets in the Red Sea have an accessory piece without a distal bifurcation and thus differ from most species of this genus from other regions of the world’s oceans.  相似文献   

10.
中国灵猫科的支序系统学分析   总被引:3,自引:0,他引:3  
选取分布于中国境内的8属9种灵猫科动物的88个骨骼性状、31个外部形态性状和1个行为性状,运用替代外群法分别以赤狐(犬科狐属)和青鼬(鼬科貂属)共同或单独作为外群进行支序分析,得出10个支序图,其步长(TL)为:106~136,一致性指数(CI)为0.581—0.660,保留指数(RI)为0.610—0.714。经合意分析得到4个相似的支序图,其TL为41—136,CI为0.581—0.732,RI为0.610—0.818,结果支持:①斑灵狸、大灵猫、小灵猫构成一个单系群,与传统分类一致(均属灵猫亚科);②椰子狸、花面狸、熊狸构成一个单系群,与传统分类一致(均属长尾狸亚科);③红颊獴、食蟹獴与灵猫科其他种为姐妹群关系(Bootstrap检验支持率100%),建议獴类为一亚科;④长颌带狸拥有较多自近裔性状如三个门齿孔,是一个高度特化的种类,其系统地位有待进一步研究。  相似文献   

11.
The external structure of postorbital organ is described in detail in seven representatives of family Astronesthidae, i.e., Borostomias elucens, B. panamensis, B. mononema, B. antarcticus, Heterophorus ophistoma, Neonesthes microcephalus, and Rhadinesthes decimus. The shape, sizes, position with respect to eye, and some other features of the structure of the postorbital organ are characteristic of the species or close species. The comparison of the structure of this organ in the above-mentioned representatives of the family Astronesthidae and earlier studied species of genus Astronesthes is given.  相似文献   

12.
中国肩花蝽属雌性交配管的形态研究   总被引:4,自引:1,他引:3  
柯云玲  卜文俊 《昆虫学报》2005,48(3):391-395
半翅目花蝽科(Anthocoridae) 昆虫的种类鉴定通常是以雄性外生殖器特征为主, 雌虫的种类鉴定一直是研究中的难点。本文研究了中国肩花蝽属 Tetraphleps 已知5个种雌虫的交配管,包括黑色肩花蝽T. aterrimus (Sahlberg)、斑翅肩花蝽T. galchanoides Ghauri、毛肩花蝽T. pilosulus Bu et Zheng、直长肩花蝽T. parallelus Bu et Zheng和玉龙肩花蝽T. yulongensis Bu et Zheng。发现交配管的构造在种内变异小、特征稳定,而在种间差别明显,可作为该属雌虫种类鉴定的可靠依据。  相似文献   

13.
The genus Bewsiella is considered to comprise a considerable number of species, despite having been regarded as monotypic. The structure of the male spermadactyl is proposed as a key character for separating congeneric species. This character seems likely to bear phylogenetic information on both the mites themselves and their hosts. Since the male of Bewsiella fledermaus Domrow, the type-species, has not been found, it is impossible to define the morphology of this species based on both sexes. Consequently, all mites that share many characters with the female of B. fledermaus are placed in a B. fledermaus species group. B. aelleni (Till) is considered as a valid species and both sexes and the protonymph are redescribed and illustrated. B. nycteris n. sp., B. emballonuris n. sp., B. cloeotis n. sp., B. haradai n. sp. and B. coelopos n. sp. are described and illustrated. The genus Bewsiella was originally allocated to the family Laelapidae and later transferred to the family Macronyssidae. Recently, the genus was returned to the Laelapidae, and some evidence supporting this action was obtained during the present study, but further studies are required for confirmation.  相似文献   

14.
An evolutionarily interesting nematode, Bursaphelenchus okinawaensis sp. nov., is described and illustrated. The new species has several characteristic morphological traits, i.e., four lateral lines in both sexes, lack of a vulval flap in females, and a triangular spicule shape and stout P4 caudal papillae in males, and characteristic biological traits, including phoretic association with Monochamus maruokai, a species of longhorn beetle, parthenogenetic reproduction, and a high frequency of dauer production. Bursaphelenchus okinawaensis sp. nov. shares several important traits with various phylogenetic groups within the genus. The new species shares its spicule shape with B. hellenicus and B. hofmanni. It shares four lateral lines, P4 caudal papillar structure (size and position), and female vulval shape with the 'hunti' group, although it was molecularly inferred to be phylogenetically closer to the 'xylophilus' group and B. africanus. The autapomorphic traits of B. okinawaensis sp. nov. are parthenogenetic reproduction and high frequency of dauer production. All other nominal Bursaphelenchus nematodes have bisexual reproduction and tightly synchronized dauer production. The unique morphological and biological traits of B. okinawaensis sp. nov. suggest genetic flexibility within the genus. The importance of the morphology and arrangement of the caudal papillae is discussed relative to the phylogeny of the genus.  相似文献   

15.
Four species of Haliotrema Johnston & Tiegs, 1922, including three new taxa, are described from the gills of two species of coral reef fishes, Zanclus cornutus (Linnaeus) and Acanthurus nigrofuscus (Forssk?l), off the Dongsha Islands in the South China Sea. Haliotrema dongshaense n. sp., from Z. cornutus, is differentiated from other existing congeneric species by its peculiar male copulatory organ, comprising a harp-shaped copulatory tube and a cup-shaped base, and two groups of short longitudinal muscles lying on either side of the vaginal vestibule. Haliotrema zigmoidocirrus n. sp. from Z. cornutus and H. nigrofusci n. sp. from A. nigrofuscus are differentiated from other congeneric species by their male copulatory organ, which has a cup-shaped base, bell-shaped middle and Z-shaped distal part, and the latter can be readily differentiated from the former by its distinctively wider haptor and longer connecting bars. Haliotrema sicklocirrus Wang, 2007, from Z. cornutus, is redescribed with additional details, including the sinistral position of the accessory piece of the male copulatory organ, the absence of eyespots and the morphology of the connecting bars.  相似文献   

16.
We investigated three rare haptorid ciliates, viz., Lagynophrya gibba Kahl (1935), Enchelys lajacola nov. spec., and Spathidium implicatum Kahl (1930), using live observation, silver impregnation, morphometry, and scanning electron microscopy. Lagynophrya gibba, which was rediscovered in peatland soil from Iceland, is referred to a new genus, Kamburophrys, and a new family, Kamburophryidae, based on a unique organelle, the brush membranoid. This structure is near the dorsal brush and composed of very narrowly spaced cilia, about 5 μm long. The genus Kamburophrys has a unique combination of features, viz., an oral cone on the oral bulge, an oblique circumoral kinety, and a subapical hump carrying the three-rowed dorsal brush and the brush membranoid. The Kamburophryidae possibly belong to the order Spathidiida. Enchelys lajacola was discovered in mud from granitic rock-pools (Lajas) in Venezuela, South America. The new species is characterized by a bottle-like shape, a macronucleus with the shape of a curved strand, a heterostichad dorsal brush, and rod-shaped toxicysts. Spathidium implicatum, which was rediscovered in an ephemeral meadow puddle near Salzburg city centre, is neotypified and referred to the genus Apertospathula because it has an open circumoral kinety.  相似文献   

17.
Abstract—Cyttaria Berkeley (Cyttariaceae, Cyttariales, Class Discomycetes), is a genus of eleven species, seven from South America and four from Australasia (Australia, Tasmania, and New Zealand). Cyttaria is a monophyletic genus defined by the following synapomorphies: fleshy to gelatinous stromata with endostromatic apothecia; and complete lack of fungal chitin in the cell walls, having instead β-1–3-glucan. All Cyttaria are exclusive parasites of Nothofagus species. A cladistic analysis of the genus was performed using 18 characters from macromorphology, micro-morphology, and phenology. Polarity of characters is based on the outgroup comparison method (using the Class Discomycetes as a whole) and on the ontogenetic criterion. A hypothetical outgroup was constructed using all plesiomorphic states. Two equally parsimonious cladograms were produced, each with 40 steps and a consistency index of 0.70. These differed in the position of the South American species C. hookeri and C. johowii. In one cladogram, C. hookeri is the sister group to the rest of the genus, and in the other, both species form a monophyletic group (ascospores ovoid) that is the sister group of the rest of the genus. Our analysis of the two characters causing this difference (position of apothecia on stroma, and shape of ascospores) supports the latter hypothesis. In both cladograms, all of the Australasian species form a monophyletic group (thick ectostroma), and, within that, two subgroups are defined: C. gunnii-C. pallida (papillae present), and C. nigra-C. septentrionalis (ectostroma with black incrustations). The Australasian species form a monophyletic group (spermatangia absent) with C. berteroi , and this last group forms a monophyletic group (conidia absent) with C. espinosae. Cytlaria darwimi and C. exigua form another monophyletic group (very thick ectostroma). Excluding C. hookeri and C. johowii, C. hariotii is the sister group to the remaining eight species.  相似文献   

18.
Seven new species of umagillid turbellarians from the intestine of aspidochirote holothurians of the Great Barrier Reef are described: Cleistogamia heronensis sp.n., C. longicirrus sp.n., C. pulchra sp.n., C. pallii sp.n., C. pyriformis sp.n. and Wahlia stichopi sp.n. as well as Paranotothrix queenslandensis gen.n. sp.n. The new genus is recognized as distinct from Notothrix Hickman, 1955 because the female system lacks a bursal valve, a significant characteristic within the Umagillidae. Examination of this and other characteristics of the family reveal that the division of the family by Stunkard & Corliss in 1950 into the sub-families Collastominae Wahl, 1910, Bicladinae Stunkard & Corliss, 1950 and Umagillinae Wahl, 1910 is supported; further, within the Umagillinae, four subgroups may be recognized: within holothurians are ( i ) the Cleistogamia group with a secondary uterus, within this group Ozametra elegans and O. striata are placed in Seritia gen.n. differing from Ozametra by the presence of both a bursal valve and a cuticular stylet, ( ii ) the Anoplodium group with a single ovary and a muscular (not cuticular) male intromittent organ and ( iii ) the Umagilla group in which Monticellina longitubu becomes a junior synonym of U. forskalensis; within echinoids ( iv ) the Syndesmis group in which Syndisyrinx is recognized a valid genus for those worms with a bursal valve and Syndesmis for those lacking this structure. Marcusella is suppressed. A visual key based upon presumed primitive and derived states is given as is a full host check list of the Umagillidae.  相似文献   

19.
Seven specimens of Rhynchodemus sylvaticus (Leidy) collected from a variety of localities in the US and having variously developed copulatory organs are believed to represent stages in the development of the copulatory apparatus. Four specimens were juveniles with under-developed male components, one specimen had a well-developed female atrium and small male component, and two specimens were mature with a male organ twice the size of the female part. In early stages, the male component had sperm ducts, seminal vesicle, and narrow atrium; more mature stages had a considerable elongated atrium with thick folds in its muscularized wall, a massive muscular bulbus; and a sigmoid ejaculatory duct opening into the large bulbar cavity. Morphological features of mature male copulatory organs in all species of the genus Rhynchodemus are basically similar whereas external body features (color and number of dorsal stripes) of these same species differ.  相似文献   

20.
The Bulinus africanus species group (Planorbidae) of freshwater snails has been reported to be represented in Zambia by two species, B. africanus (Krauss) and B. globosus (Morelet), both named as intermediate hosts for Schistosoma haematobium. Uncertainty in identification of these snails from morphology led to the present investigation, combining morphometry (shell and copulatory organ) with enzyme analysis. Observations of both kinds were made usually on the same individual snails, from collecting sites mostly in the Lusaka area or at Lake Kariba. Particular attention was given to the proportional relationship between the penis sheath and the preputium of the copulatory organ, a character used previously to distinguish B. africanus from B. globosus in south-eastern Africa. The enzyme profile MDH-1, AcP-2, PGD-1 and PGM-2 was common to all snails examined from 25 populations; GPI and HBDH were polymorphic. The enzyme data indicate that the samples represent a single species. Shell characters varied continuously. The copulatory organ was generally of the form known for B. globosus. Although the copulatory organ of a few individuals had proportions overlapping the range reported for B. africanus, the present variation was continuous and was not bimodal. It is concluded that all these specimens are conspecific and may be identified as B. globosus. Previous identifications of B. africanus from Zambia appear to need substantiation and it seems that if this species is present at all in the sampled areas, it must be uncommon. It is relevant in regard to possible strain differences within S. haematobium in Zambia, that our observations indicate that only a single species of intermediate host is involved in transmission.  相似文献   

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