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1.
Stephanofilaria thelazioides n. sp. (Filarioidea: Filariidae: Stephanofilariinae) is described from a hippopotamus Hippopotamus amphibius. This nematode is close to S. dinniki Round, 1964, a parasite of the black rhinoceros Diceros bicornis in Africa, but differs from it in the number of cuticular spines surrounding the mouth, the arrangement of the cloacal papillae and the measurements of the spicules, gubernaculum and microfilariae. Species of the genus Stephanofilaria possess spines on the head which have been derived by modification of the sensory papillae. S. thelazioides is the most primitive species of the genus and has the least modified arrangement of these papillae, with six bifid internal labial spines, four bifid external labial spines and four cephalic papillae. The genus appears to have diversified in various mammals which have in common a thick skin, such as rhinoceroses, elephants, buffaloes and now the hippopotamus. It appears to have become adapted secondarily to domestic bovines, initially in Asia and subsequently in North America. 相似文献
2.
Macrobothridium rhynchobati n. g., n. sp. from the guitarfish Rhynchobatus granulatus in Kuwaiti waters in the Arabian Gulf is described and figured. The new genus differs from Echinobothrium in having a short unarmed peduncle and a posterior sucker-like structure in the terminal proglottid. It differs from Ditrachybothridium in having a powerful rostellum with dorsal and ventral groups of hooks and in having unarmed bothridia. A new family, the Macrobothridiidae, assigned to the order Diphyllidea is erected. Larval forms are described and figured. 相似文献
3.
Stoyanka R. Stoitsova Boyko B. Georgiev Gergana P. Vasileva Mimi Jordanova 《Acta zoologica》2001,82(3):241-250
The rostellar apparatus of Fernandezia spinosissima is examined by light and transmission electron microscopy. It is described as composed of rostellum, pseudoproboscis, and two groups of glandular syncytia, one in the rostellum and the other inwards to the rostellum and the pseudoproboscis. The rostellum is a discoid cushion with muscular walls. There are numerous thin vertical muscular fibres and glandular syncytia inside it. Its tegument has slender microtriches. Peripherally, the rostellum is encircled by thin muscle fibres that protrude anteriorly between rostellar hooks and group posteriorly to form retractors. The rostellar hook guards are associated with a complicated network of muscles and nerves. The pseudoproboscis is a thick-walled ring around the apical part of the scolex adjacent to the rostellum. Its tegument has microtriches with modified spines that are interpreted as accessory spines. The walls of the pseudoproboscis possess a loose structure of parallel muscular fibres and glandular processes. The glandular syncytia, interpreted as modified tegumental perikarya, have basophilic cytoplasm and stain positively for protein and carbohydrate. They form cellular processes, which protrude to reach to the tegument. These results provide structural details characterising one of the rostellar types recognized in the order Cyclophyllidea, i.e. the davaineid rostellar apparatus. 相似文献
4.
TIMOTHEÜS VAN DER NIET WILLIAM R. LILTVED STEVEN D. JOHNSON 《Botanical journal of the Linnean Society. Linnean Society of London》2011,166(4):417-430
Superficial similarities among unrelated species are often a result of convergent evolution and can cause considerable taxonomic confusion. A case in point is Satyrium eurycalcaratum , described here as a new species, which has been confused with several other Satyrium spp. with similar long‐spurred, white flowers. A phylogenetic analysis, based on molecular data, indicated that S. eurycalcaratum is not closely related to any of the species with which it has been previously confused. A comparative analysis of morphological characters in the seven South African Satyrium spp. with long‐spurred, white flowers showed that each of these, including S. eurycalcaratum , is characterized by a unique combination of traits. Despite the similarity in pollination syndrome characters, such as spur length and flower colour, variation in rostellum structure was particularly pronounced and four distinctive forms were present. There was no phylogenetic signal in patterns of interspecific rostellum variation, as some closely related species had different rostella, whereas some distantly related species shared similar rostellum structures. We therefore conclude that the use of rostellum traits in conjunction with phylogenetic evidence can resolve species delimitations among orchid species that share the same pollination syndrome. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 166 , 417–430. 相似文献
5.
Froghood: Postmetamorphic development of the rock river frog Thoropa miliaris (Spix, 1824) (Anura,Cycloramphidae)
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Thoropa miliaris is a frog species endemic to the Brazilian Atlantic Rainforest, inhabiting wet rocky habitats. Males of this species present nuptial excrescences, which are keratinized spines on the surface of some fingers and internal metacarpal tubercles. Although these spines are usually associated with male adulthood, no details of their development are available. To investigate the sequence of spines' appearance, we correlated the number of spines with size and age, which was estimated by skeletochronology. We studied individuals collected from Rio de Janeiro, Brazil. There was significant correlation between size of individuals and number of spines and between age and number of spines in the callosities. The first spines appeared in metacarpal–phalangeal articulation of finger II, when specimens were 1 year old. The estimated growth curve did not show stabilization at any age. We considered the degree of development of the nuptial excrescences as a proxy for sexual maturity and so individuals may already be sexually active by 1 year of age. Estimated longevity of T. miliaris is similar to that estimated for other tropical species of frogs. Although growth in anuran species is considered to be undetermined, in T. miliaris, it seems to fit either undetermined or determined models. 相似文献
6.
D. R. R. BURT F.L.S. 《Zoological Journal of the Linnean Society》1979,65(1):71-82
Two new species of Eurycestus Clark 1954 are described from the American avocet Recuruirostra americana Gmelin 1788. Eurycestus is a genus of disproportionately wide cestodes in which suckers and rostellum are apparently wanting and which have complete duplication of reproductive system in each segment. The new species E. falciformis and E. latissimus spp. nov. differ from E. avoceti Clark 1954; E. falciformis resembles E. avoceti as figured in Clark's (1954) plate I, E. latisrimus resembles E. avoceti as depicted in Clark's (1954) plate II, but the three species differ, the diagnostic characters being shape of the strobila, size of the cirrus-sac, number of testes and armature of the cirrus, the last mentioned being the most easily recognized constant differentiating character. E. latissimus measuring up to 33 mm broad, and less than 1 mm in length, has, in each side, 31–44 testes, a cirrus-sac 333–447 μm long by 45–47 μm in diameter and a cirrus with 14–16 longitudinal rows of strong rose-thorn-shaped spines, measuring 7 μm high; while E. falciformis, 12–20 mm wide by 1.7-2.4 mm long has, in each side, 27–35 testes, a cirrus-sac 355-320 μm long and 43-35 μm in diameter with a cirrus armed with 20–24 longitudinal rows of slender spines 4.5 μm long. In the holotype of E. avoceti the cirrus-sac measures 240–260 μm long by 55-51 μm in diameter and the cirrus is armed with over 40 longitudinal rows of minute spines 1.5-2 μm long. It also shows a reticulate uterus but the number of testes cannot be determined in it. A young avocet (R. auosetta) taken in the Camargue in the south of france was found by Baer (1968) to contain free, scolex-less strobilae which he identified as E. avoceti Clark in addition to separate scoleces embedded in the intestinal mucosa. He considered that the scoleces, dilepidid in type, belonged to the free strobilae, which if correct, adds to our knowledge of E. avoceti Clark and assigns this cestode to the Dilepidinae. 相似文献
7.
Leslie A. Chisholm 《Systematic parasitology》1995,30(3):207-211
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
8.
Mohammed Hasan Ibraheem 《Acta zoologica》2006,87(3):159-169
The morphology of juvenile and adult stages of Acanthostomum spiniceps and A. absconditum, from bagrid fish of the river Nile in Egypt, was studied with both light and scanning electron microscopy. In early juveniles, circumoral spines are absent and the entire body surface is covered with tegumental spines. Late juveniles show gradual differentiation of the circumoral tegument into a collar of spines associated with a reduction in density of tegumental spines at the posterior extremity of the body. Genital primordia appear when juveniles are about 1.75 mm long. The distributions of tegumental spines on adult A. spiniceps and A. absconditum are similar. Spines are denser on the dorsal and ventral surfaces of the anterior and middle parts of the body and less dense towards the posterior end. The tegumental fold surrounding the ventral sucker of A. absconditum has spines while the fold of A. spiniceps lacks them. The most important morphological features differentiating both species are the number of circumoral spines, body shape, ratio of body length to width, sucker sizes, and the presence or absence of spines on the ventral sucker. 相似文献
9.
C. Díaz C. Yanes L. Medina C. M. Trujillo M. Monzn L. Puelles 《Journal of morphology》1990,203(3):293-300
Using Golgi techniques we have studied neuronal cell types in the anterior dorsal ventricular ridge (ADVR) of the adult lizard Gallotia galloti. Multipolar, bitufted, and juxtaependymal neuronal forms were found. The multipolar and bitufted neurons are present in both the periventricular and central ADVR zones. Multipolar neurons can be subdivided into multipolar neurons with polygonal somata and four to six main dendritic trunks and multipolar neurons with pyramidal somata and three or more dendritic trunks. The former are the cells most frequently impregnated in the ADVR. In the population of bitufted neurons, we distinguish subtypes I, II, and III according to the number of dendritic trunks that emerge from the somata. Juxtaependymal neurons are restricted to a cell-poor zone, adjacent to ependymal cells. Their dendrites either are orientated parallel to the ventricular surface or extend into the periventricular zone. The dendrites of ADVR neurons have pedunculated spines with knob-like tips. However, such spines do not appear on the somata or on the primary dendritic trunks. The number of spines is scarce or moderate. The periventricular neuronal clusters contain two to five cells. The morphology of these neurons is mainly multipolar, but we also found some bitufted neurons. 相似文献
10.
Martin V. Sørensen Iben Heiner Ole Ziemer Birger Neuhaus 《Helgoland Marine Research》2007,61(4):247-265
One new kinorhynch genus and species and one new species from the genus Zelinkaderes are described from sandy sediment off Fort Pierce, Florida. The new genus and species, Tubulideres seminoli gen. et sp. nov. is characterized by the presence of the first trunk segment consisting of a closed ring, the second segment
of a bent tergal plate with a midventral articulation and the following nine segments consisting of a tergal and two sternal
plates. Cuspidate spines are not present, but flexible tubules are located on several segments, and in particular concentrated
on the ventral side of the second segment. Middorsal spines are present on all trunk segments and are alternatingly offset
to a position slightly lateral to the middorsal line. Zelinkaderes brightae nov. sp. is characterized by its spine formula in having middorsal spines on trunk segments 4, 6 and 8–11, lateroventral
acicular spines on segment 2, lateral accessory cuspidate spines on segments 2 and 8, ventrolateral cuspidate spines on segments
4–6 and 9, lateroventral acicular spines present on segments 8 and 9, and midterminal, lateral terminal and lateral terminal
accessory spines on segment 11. The spine formula of Z. brightae nov. sp. places it in a position in between Z. submersus and a clade consisting of Z. klepali and Z. floridensis. The new findings on Z. brightae nov. sp. have led us to propose an emended diagnosis for the genus. 相似文献
11.
Pamela Balogh 《American journal of botany》1982,69(7):1119-1132
The orchid family is divided into five subfamilies and further divided into 21 tribes and 63 subtribes (Dressler, 1981). Subtribe Spiranthinae (tribe Cranchideae, subfamily Spiranthoideae) is treated here as consisting of approximately 250-300 species in 16 genera. These genera are Brachystele, Buchtienia, Cutsis, Cyclopogon, Deiregyne, Discyphus, Eurystyles, Hapalorchis, Odontorrhynchos, Pelexia, Pseudogoodyera, Sarcoglottis, Sauroglossum, Schiedeella, Spiranthes, and Stenorrhynchos. Eleven of these genera may be grouped into four generic alliances using the rostellum/viscidium attachment as the basis for these alliances. The Brachystele alliance includes Brachystele, Sauroglossum, and Odontorrhynchos and has a very reduced rostellum which is usually inseparable from the viscidium. The Pelexia alliance includes Cyclopogon, Pelexia, and Sarcoglottis and has an elongate, broad, laminar rostellum which is partially adherent to the viscidium. The Spiranthes alliance includes Discyphus, Hapalorchis, and Spiranthes and has a broad, laminar rostellum which is centrally adherent to the viscidium. The Stenorrhynchos alliance includes Schiedeella and Stenorrhynchos and has a subulate rostellum which is ensheathed by the viscidium. Previous studies (Schlechter, 1920) of this subtribe were based on characteristics of the rostellum and perianth. Pollinarium morphology is reported for the first time. 相似文献
12.
Larisa G. Poddubnaya Elena Mishina Alexander E. Zhokhov David I. Gibson 《Systematic parasitology》2010,75(1):59-73
The tegumental surface of a new strigeid metacercaria, Nematostrigea sp., which is a parasite of the freshwater fish Channa gachua (Hamilton) in central Vietnam, is described for the first time using scanning (SEM) and transmission (TEM) electron microscopy.
In addition to the general tegumental surface in various parts of the body, details of the surface of the suckers, lappets
and holdfast organ are presented, as are variations in the form and distribution of the body spines. As good taxonomic criteria
are few in diplostomoid metacercariae at both specific and generic levels, a number of the ultrastructural features revealed
may prove to represent taxonomically informative characters. These include the presence of: two rings of dome-shaped papillae localised at different levels on the rim of the oral sucker,
a single ring of ciliated papillae on the inner margin of the ventral sucker and a band of dome-shaped papillae along the
lateral margins of the broad body-fold in the ventral forebody; an unarmed oral sucker and anteroventral surface of the forebody,
although the latter bears protuberant secretory pores; an armed ventral sucker covered by six-pointed spines, except on its
rim; multi-pointed spines along the dorsal and ventral sides of the forebody, with the number of their teeth increasing posteriorly;
multi-pointed spines on the forebody which gradually transform into single-pointed, more widely distributed spines on the
hindbody, disappearing completely at posterior end of the body; the surface of the lappets with a particular distribution
of pores leading to three types of secretory glands and three topographical modifications (areas where the surface is smooth,
bears digitiform processes or bears recurved, dagger-shaped spines); and the surface of the holdfast organ which is covered
with densely packed, straight or slightly curved, simple spines on its lateral surface but is smooth medially. 相似文献
13.
Abstract A new species, Arrhopalites chungbaishanensis is described from Mt. Changbai, northeast China. The present species shares some characters with A. octacanthus, but it differs from the latter by the number of vertical thick spines and manubrial dorsal setae, types of dental setae and the absence of tunica on unguis. In comparison with the other congeneric species, the mast striking character of the present species is its special shapes of the C-series setae besetting on sixth abdominal segment. 相似文献
14.
Priscila Izabel Tremarin Rosildo Santos Paiva Thelma Veiga Ludwig Lezilda Carvalho Torgan 《Phycological Research》2013,61(4):292-298
This paper describes a new diatom species, Aulacoseira calypsi Tremarin, Torgan & Ludwig, from specimens in plankton samples from Água Preta lake. This Amazonian lake is a shallow mesotrophic environment situated in northern Brazil. The species is characterized by long filaments united by spatulate linking spines, obovate to conic separation spines, a valve surface variably ornamented, straight striae on the mantle, a narrow ringleist, and one row of sessile rimoportulae near the ringleist. Aulacoseira calypsi's morphometric features are compared with the following similar species: Aulacoseira nygaardii (Camburn) Camburn & Charles, Aulacoseira lacustris (Grunow) Krammer, Aulacoseira coroniformis Pearce & Cremer, Aulacoseira occulta Siver & Hamilton, Aulacoseira lancea Siver & Hamilton, Aulacoseira gessneri (Hustedt) Simonsen, and Aulacoseira islandica (Müller) Simonsen. The species shares similarities as to frustule size, striation pattern, and narrowness of ringleist; but differs in the morphology of separation and linking spines, and the number and position of the rimoportulae. 相似文献
15.
Secretary activities associated with the rostellum of adult Echinococcus granulosus were studied using histological, histochemical, and ultrastructural techniques, following rapid fixation of the cestodes in situ in the small intestine of the anaesthetised dog. Studies concentrated on the host-parasite interface from 30 to 35 days postinfection. At this time, contraction of the muscular rostellar pad appeared to be associated with extension of the apical rostellum into a crypt of Lieberkühn. Crypt invasion by the apical rostellum coincided with morphological changes and secretory activity in a group of modified tegumental cells, previously referred to as the rostellar gland. Secretory material, a cystine-rich protein, was observed in the nuclei and cytoplasm of the rostellar gland cells. Release of this material into the interface was seen only following crypt invasion by the apical rostellum. Although the mechanism of release is not clear, it may be analagous to holocrine secretory mechanisms, since apparent degeneration of the rostellar gland region was associated with secretion. Possible functional activities of the secretion associated with hook formation, nutrition, regulation, adhesion, and protection are discussed. 相似文献
16.
Vinay P. Padate Sherine Sonia Cubelio K. V. Jayachandran 《Marine Biology Research》2020,16(4):209-218
ABSTRACT Homolodromia rajeevani, a new species of deep-water homolodromiid sponge crab, is described from the northern Indian Ocean (Arabian Sea, depth 957 m, and Bay of Bengal, 645 m), and is the first record of the genus from the area. This species resembles the western Indian Ocean species, namely, Homolodromia bouvieri Doflein, 1904, in having 2 terminal spines on the propodi of the last two pereopods, but can be easily distinguished from the latter species by the inflated carapace, simple long setae on carapace and appendages, slender pseudo-rostral spines separated by a U-shaped base, and a slender arched dactylus of cheliped with maximum elevation at proximal part which bears broadly circular depressions with sparse setae. The most diagnostic character is the higher number of spines on the occlusal surfaces of propodal thumbs and dactyli of the pseudochela of the last two pereopods as compared to H. bouvieri. A key for the identification of the species under the genus Homolodromia is also provided. http://zoobank.org/urn:lsid:zoobank.org:pub:48894F49-5124-4723-9FF2-3D30FB536DA5 相似文献
17.
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
18.
The hemiramphid,Oxyporhamphus, is a flyingfish (exocoetidae) 总被引:1,自引:0,他引:1
Osteological and myological studies on the caudal complex of flying fishes (Exocoetidae) plusOxyporhamphus (of Hemiramphidae) revealed the following shared derived conditions: 1) neural spines of preural vertebrae broader than haemal
spines; 2) spur present on posterior margin of preural vertebra 2;3) upper hypural plates steeply angled; 4) lower hypural
plate extending strongly posteriorly; 5) lower hypural plate deeply surrounded by caudal fin rays; 6) flexor ventralis well
developed, arising from neural spines; 7) flexor ventralis externus well developed; 8) adductor dorsalis well developed.Oxyporhamphus and exocoetids also share a lower jaw of adults not elongate and the premaxilla with a straight anterior margin. Therefore,Oxyporhamphus is transferred to the Exocoetidae, with which it shares a total of 10 derived conditions. 相似文献
19.
Echinobothrium chisholmae n. sp. is described from Rhinobatos typus Bennett (Rhinobatidae), collected from Heron Island, Great Barrier Reef, Australia. E. chisholmae differs from all congeners in possessing 11 hooks in each dorsal and ventral group on the rostellum and groups of 3-6 hooklets on either side of the hooks. A single metacestode of E. chisholmae was collected from the decapod crustacean Penaeus longistylus Kubo. Yellow pigmentation of the cephalic peduncle in immature adults is caused by the accumulation of large vesicles in the distal cytoplasm of the tegument. The vesicles probably provide materials for spine formation. Ultrastructural examination of the rostellar musculature revealed that the muscles are stratified (striated-like), consisting of a periodic repetition of sarcomeres separated by perforated Z-like lines that are oblique to the long axes of the myofilaments. 相似文献
20.
Mohammed Hasan Ibraheem 《Acta zoologica》2007,88(2):173-178
The present study concerned the morphology and surface ultrastructure of a plagiorchid, Glossidium pedatum, from bagrid fish of the river Nile in Egypt. Adult G. pedatum have an elongate body, tapered towards the anterior and posterior ends. Their oral sucker is small, sub‐terminal and rounded, measuring 0.200 mm in diameter. Sensory papillae around the oral sucker usually occur in small clusters of three to eight each. The ventral sucker is large, situated at the anterior end of the second third of the body, 0.299 mm in diameter, and is surrounded by three pairs of sensory papillae. Both suckers have rounded rims covered by tegumental spines. On the anterior part of the ventral surface of the body tegumental spines are small, pointed and closely spaced. A small triangular area of tegument anterior to the ventral sucker is devoid of spines. Tegumental spines on the mid‐region of the body slightly increase in size and number, especially towards the lateral aspects and posterior to the ventral sucker. Towards the posterior end of the body the spines progressively decrease in both size and number. The dorsal side exhibits similar surface features but the spines are less numerous and slightly smaller. 相似文献