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The morphology of relaxed cystacanths of polymorphid acanthocephalans collected from notothenioid fishes in the Beagle Channel
(Magellanic subregion of sub-Antarctica) is described. A parasite of birds, Andracantha baylisi (Zdzitowiecki, 1986), was found in Patagonotothen longipes and Champsocephalus esox. It has: a proboscis 0.82–0.89 mm long; a proboscis hook formula of 16 rows of 9/10–10/11, including 4–5 basal hooks; distal
hooks with the longest blades; a fore-trunk not separated from the hind-trunk by a constriction; large somatic spines arranged
in two zones separated by a zone of small, loosely dispersed spines; and only the anterior 36–40% of ventral side of the trunk
is covered with spines. One male specimen of Corynosoma sp. was found in Patagonotothen tessellata. It differs from A. baylisi in that the distal proboscis hooks are similar in length to the prebasal hooks, it has a smaller proboscis (0.77 mm) and
in the distribution of the somatic spines, which are contiguous with the genital spines on the ventral side of the trunk and
lack a zone of small spines between zones of larger spines. A parasite of seals and fur seals, Corynosoma evae Zdzitowiecki, 1984, was found in P. longipes and Champsocephalus esox. It has: a proboscis 0.61–0.78 mm long; a proboscis hook formula of 20–22 rows of 12–13, including 3/4–4 basal hooks; prebasal
hooks with the longest blades; a trunk divided into fore-trunk and hind-trunk; somatic spines covering the anterior 64–74%
of the ventral side of the trunk; genital spines present only in males; and a terminal genital opening in both sexes. Corynosoma beaglense n. sp. was found in Champsocephalus esox. It has: an almost cylindrical proboscis (length 0.52–0.56 mm); a proboscis hook formula of 16 rows of 9/10–10/11, including
4–4/5 basal hooks; distal hooks shorter than the prebasal hooks; a fore-trunk not separated from the hind-trunk by a constriction;
somatic spines contiguous with the genital spines on the ventral side of the trunk of the male and covering the entire length
of the ventral side of the female trunk, and the presence of genital spines surrounding the terminal genital pore of the male.
The definitive host of this species is unknown. 相似文献
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Weekers PH Murugan G Vanfleteren JR Belk D Dumont HJ 《Molecular phylogenetics and evolution》2002,25(3):535-544
The nuclear small subunit ribosomal DNA (18S rDNA) of 27 anostracans (Branchiopoda: Anostraca) belonging to 14 genera and eight out of nine traditionally recognized families has been sequenced and used for phylogenetic analysis. The 18S rDNA phylogeny shows that the anostracans are monophyletic. The taxa under examination form two clades of subordinal level and eight clades of family level. Two families the Polyartemiidae and Linderiellidae are suppressed and merged with the Chirocephalidae, of which together they form a subfamily. In contrast, the Parartemiinae are removed from the Branchipodidae, raised to family level (Parartemiidae) and cluster as a sister group to the Artemiidae in a clade defined here as the Artemiina (new suborder). A number of morphological traits support this new suborder. The Branchipodidae are separated into two families, the Branchipodidae and Tanymastigidae (new family). The relationship between Dendrocephalus and Thamnocephalus requires further study and needs the addition of Branchinella sequences to decide whether the Thamnocephalidae are monophyletic. Surprisingly, Polyartemiella hazeni and Polyartemia forcipata ("Family" Polyartemiidae), with 17 and 19 thoracic segments and pairs of trunk limb as opposed to all other anostracans with only 11 pairs, do not cluster but are separated by Linderiella santarosae ("Family" Linderiellidae), which has 11 pairs of trunk limbs. All appear to be part of the Chirocephalidae and share one morphological character: double pre-epipodites on at least part of their legs. That Linderiella is part of the Polyartemiinae suggests that multiplication of the number of limbs occurred once, but was lost again in Linderiella. Within Chirocephalidae, we found two further clades, the Eubranchipus-Pristicephalus clade and the Chirocephalus clade. Pristicephalus is reinstated as a genus. 相似文献
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Habitat associations with topography and canopy structure of tree species in a tropical montane forest on Mount Kinabalu,Borneo 总被引:1,自引:0,他引:1
Habitat associations with topography and canopy structure of 42 abundant tree species were studied in a 2.74-ha plot of tropical
montane forest on Mount Kinabalu, Borneo. Many of these species belong to the same higher taxa including eight families and
four genera. Analysis of intraspecific spatial distributions for stems ≥ 10 cm diameter revealed that 28 species (including
all six species of Fagaceae) showed aggregated distributions at the 100-m2 and/or 400-m2 scales, and that 20 species showed habitat associations with topography by torus-translation tests; 17 species showed both
characteristics. Species' associations with the local canopy structure were characterized by crown position index (CPI), which
was defined relative to neighbour trees. The CPI differed greatly among individual stems at 10–40 cm diameter, and 19 species
showed significantly different frequencies of crowns exposed vertically versus those shaded beneath the canopy. Mean growth
rates at 10–40 cm diameter and size distributions of species were not related to topographic associations, but were explained
by the associations with canopy structure; species with more exposed crowns grew faster and had less positively skewed distributions.
Diversity in habitat associations was manifest between two genera (Syzygium and Tristaniopsis) in the family Myrtaceae and among species in these genera, but was less evident in other families and two genera (Garcinia and Lithocarpus).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Tomáš Pavlíček Csaba Csuzdi Mete Mısırlıoğlu Boris Vilenkin 《Biodiversity and Conservation》2010,19(7):1989-2001
The analysis presents earthworm distribution in eight designated tectonic units (C—Cyprus, EP—East Pondites, ET—East Taurus
block, Sc—Sakarya continent, Kb—Kırşehir block, L—the Levant, TM—Taurus–Menderes block, WP—West Pondites) in the East Mediterranean
region (EM). It represents a full list of earthworm species (N = 81) of the region and reveals significant faunal similarities between Sc + WP, and between Kb + TM. The new Sc + WP unit
is characterized by the presence of archaic (Spermophorodrilus) as well as modern earthworm fauna. In contrast, the second newly established Kb + TM unit is characterized by poorly presented
earthworm autochthonous fauna and by a lack of endemic species. The analysis done on the species list (N = 73) representing the autochthonous family Lumbricidae showed statistically supported separation of L and EP between themselves
and from other designated units. The Levant, part of the Arabian tectonic plate, is characterized by a high level of endemism
in ancient (Healyella) and modern (Dendrobaena, Perelia) genera, and by the lack of archaic genera. The EP harbors unique species representing archaic (Eophila), ancient (Healyella), and modern (Allolobophora, Aporrectodea,
Dendrobaena and Eisenia) earthworm genera in the EM. The analysis also indicates origin of earthworm fauna in TM and faunistic relationships among
the designated units. Clearly, the present-day division of the EM earthworm fauna shows recognizable influences of tectonic
history. 相似文献
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Juan Carlos Zenteno Marisol López Clementina Vera Juan Pablo Méndez S. Kofman-Alfaro 《Human genetics》1997,100(5-6):606-610
We report a Mexican family in which two sibs were identified as “classic” XX males without genital ambiguities. Molecular
studies revealed that both patients were negative for several Y sequences, including SRY. A review of familial cases disclosed that this is the first family where a complete male phenotype was observed in Y-negative
XX male non-twin brothers. These data suggest that an inherited loss-of-function mutation, in a gene participating in the
sex-determining cascade, can induce normal male sexual differentiation in the absence of SRY.
Received: 5 March 1997 / Accepted: 9 May 1997 相似文献
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Triaenorhina burti n. sp. (Cyclophyllidea: Paruterinidae) is described from Harpactes fasciatus (Trogoniformes: Trogonidae) from the Southern Province of Sri Lanka. The new species is characterised by: a body 24–32 mm long; 44 rostellar hooks alternating in two closely adjacent regular rows, with lengths of 63–65 μm (anterior row) and 39–41 μm (posterior row); regularly alternating genital pores; testes divided into two groups by the ovary and vitellarium; a gravid uterus forming a single oval sac; and a cylindrical paruterine organ not reaching the anterior proglottis margin. A key to the seven recognised species of Triaenorhina Spasskii & Shumilo, 1965 is presented. 相似文献
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On the patterns of abundance and diversity of macrolichens of Chopta-Tunganath in the Garhwal Himalaya 总被引:1,自引:0,他引:1
Negi HR 《Journal of biosciences》2000,25(4):367-378
A total of 3211 colonies of macrolichens, from twelve 50 m × 10 m plots distributed across four macrohabitat (vegetation)
types between 1500 m–3700 m in the Chopta-Tunganath landscape of the Garhwal Himalaya, yielded 13 families with 15 genera
and 85 species.Lobaria retigera stood out as a broad-niched generalist species with moderate levels of abundance in all the three major microhabitats, viz.
rock, soil and wood across 83% of all the plots sampled, whereasUmbilicaria indica emerged as an abundantly occurring specialist confined to rock substrates.Heterodermia incana andLeptogium javanicum appeared to be rare members of the community as they were encountered only once during the field survey. Woody microhabitats
turned out to be richer than rock and soil substrates for macrolichens. Amongst the macrohabitats, middle altitude (2500–2800
m)Quercus forest was richest in species and genera followed by high altitude (2900–3200 m)Rhododendron forest, higher altitude grasslands (3300–3700 m) and then the lower elevation (1500 m)Quercus forest. Species, genus and family level alphaas well as beta-diversities were significantly correlated with each other, implying
that higher taxonomic ranks such as genera may be used as surrogates for species thus facilitating cost- and time-effective
periodic monitoring of the biodiversity of macrolichens. Dynamics of the diversity of lichen communities in relation to various
forms of environmental disturbance including livestock grazing and tourism as dominant land use activities in the higher Himalaya
need further research. 相似文献
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João Miguel de Matos Nogueira Kirk Fitzhugh Pat Hutchings Orlemir Carrerette 《Marine Biology Research》2017,13(6):671-692
Members of the 12 known species of the family Telothelepodidae, plus individuals of three additional undescribed species, were examined to infer phylogenetic relationships within the family and evaluate the status of genera. The outgroups include members of three species of Polycirridae and three of Thelepodidae. Members of 21 species, including both in- and outgroups, were coded for 47 subjects (‘characters’) and 109 characters sensu stricto (subject-predicate relations or ‘states’). The results, based on 15 minimum-length trees, each 103 steps long, suggest that telothelepodids should be divided into four genera, according to the morphology of the lower lip, presence or absence of eyespots, and visibility of segment 1. By necessity two of these genera are monotypic and plesiomorphic to two monophyletic genera; the latter two genera with five and eight species, respectively. Telothelepus, Parathelepus and Rhinothelepus are redefined, and the new genus Mesopothelepus gen. nov. is erected, all to accommodate the phylogenetic hypotheses presented. The problem of properly defining monotypic supraspecific taxon names as representative of phylogenetic hypotheses is discussed in relation to the inherent limitations of Article 13.1.1 of the International Code of Zoological Nomenclature.
http://zoobank.org/urn:lsid:zoobank.org:pub:8C05DBD2-8226-4738-BF4A-E623A97ACB75 相似文献
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Unique set of copulatory organs in mantises: Concealed female genital opening and extremely asymmetric male genitalia
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Several insects exhibit strong asymmetry in male genital shape, but the functions of this asymmetry is unknown. In the four species of the family Mantidae belonging to the genera Tenodera, Statilia and Hierodula, male genitalia consist of a more complex left‐side lobe, with two well‐pointed sclerotized processes, the apical process (paa) and the distal process (pda). Female genitalia are symmetric, and the genital opening (gonopore) is concealed by placement of the ovipositor (ovi) into the subgenital plate (sgp). Mating with experimental males, in which either paa or pda was cut, demonstrated that paa is essential for successful copulation. By fluorescence detection of the surface of females mated with males in which the paa was coated with fine fluorescent beads, the paa attachment site was determined to be the left edge of the female sgp. This finding suggests that copulation begins with exposure of the female gonopore by the male hooking the paa to the sgp and unfastening the ovi from the sgp, as associated with other parts of the male genitalia. The extremely asymmetric male genitalia also determine their mating posture. The male, mounting the female, bends his abdomen from the right side of his mate to attach his paa to her sgp. We found no antisymmetry in male genitalia, and never observed reversal (leftward) abdominal bending by the males. This was the fixed mating posture, even in virgin males, suggesting its innateness. 相似文献
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Teresa Ribeiro Jo?o Loureiro Concei??o Santos Leonor Morais-Cec��lio 《Tree Genetics & Genomes》2011,7(6):1113-1122
The Fagaceae is one of the most important plant families in European forest ecosystems, and it includes several genera distributed
in the Northern hemisphere. In this work we studied the genome organization and evolution within the family, by karyotyping
and physically mapping rDNA in ten European and Asian species of the genera Fagus, Quercus, and Castanea. All of the species studied had a chromosome number of 2n=2x=24, except for the first report of a single individual of Quercus suber which proved to be triploid (2n=3x=36). The rDNA physical mapping revealed several patterns: the dominant one is present in European and Asian Quercus subgenus Quercus, and in Castanea sativa and Castanea crenata, consisting of two 18S–25S rDNA loci (one subterminal major and one pericentromeric minor) and one 5S rDNA pericentromeric
locus. In Fagus sylvatica and in Quercus sessilifolia, different patterns were observed: four terminal 18S–25S rDNA loci and two 5S rDNA pericentromeric loci in the former, and
five 18S–25S rDNA loci (three terminal and two intercalary) and one 5S rDNA pericentromeric locus in the latter. In Castanea mollissima a distinct rDNA distribution pattern with two intercalary 18S–25S rDNA loci and two 5S rDNA was found. These findings suggest
rDNA loci restructuring during Castanea evolution, and variability of 18S–25S loci between Quercus and Cyclobalanopsis subgenera. 相似文献
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On potentials and relevance of the use of copulatory structures in anostracan taxonomy 总被引:1,自引:1,他引:0
This paper reviews and extends the knowledge of anostracan penile morphology and its taxonomic significance. Since Linder‘s
pioneering classification(based partly on male genital characters), the morphology of both basal and distal penile parts has
been applied repeatedly to reorganize or establish higher anostracan taxa, or to extend their diagnoses. In general, the configuration
of both basal and distal penile structures follows a constant pattern in well-defined genera. Size and shape of processes
and spinulation on the basal (in Linderiella and Chirocephalidae) and the distal parts (in Parartemia), however, may show
inter-specific differences. Variability in penile structures in the current genus Brachinella indicates the need for a taxonomic
revision of this genus. Similar intra-generic penis morphology may contribute to hybridizability of congeners and validate
Dubois‘genus concept for use in anostracans.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Checklist of the Anostraca 总被引:13,自引:13,他引:0
In this checklist, we number the named anostracan fauna of the world at 258 species and seven subspecies oraganized in 21 genera. The list contains all species described through 31 December 1993, and those new species names made available in previous pages of this volume. The most species rich genus isStreptocephalus with 58 described species level taxa.Chirocephalus with 43,Brachinecta 35, andBranchinella 33 occupy the next three places. With the exception ofBranchipodopsis andEubranchipus each having 16 species, all the other genera include less than 10 species each. The need for zoogeographic study of these animals is demonstrated by the fact that almost 25% of the named taxa are known only from their type localities. 相似文献
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Study on rugose coral fauna of the Sifengya Formation (early Telychian) and Daluzhai Formation (mid-late Telychian) in Daguan
area, northeast Yunnan Province, China was carried out. Rugose coral fauna of the Sifengya Formation included 18 genera and
34 species, while Daluzhai Formation with nine genera, ten species. We described rugose coral fauna (12 genera, 19 species)
including one new genus and five new species, i.e. Protoketophyllum daguanense gen. et sp. nov., Crassilasma huanggexiense sp. nov., Pseudophaulactis heae sp. nov., P. convolutus sp. nov., and Shensiphyllum minor sp. nov. The characteristics and geological significance of rugose coral fauna of Sifengya Formation and Daluzhai Formation
were analyzed. Particularly, rugose coral fauna of the Sifengya Formation represent early Telychian rugosan fauna in the Upper
Yangtze region and improve the sequences of early Silurian (Llandovery) rugose coral assemblages in Yangtze region. It is
therefore very meaningful to further analyze radiation period of rugose coral fauna in such epoch.
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Translated from Acta Palaeontologica Sinica, 2005, 44(2): 229–246 [译自: 古生物学报, 2005, 44(2): 229–246] 相似文献