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1.
We report 3 species of the digenean genus Parallopharynx, 1 previously undescribed, from the Area de Conservación Guanacaste (ACG) in northwestern Costa Rica. Parallopharynx gonzalezi, which was originally described in Basiliscus sp. and Ctenosoura similis from central Costa Rica, inhabits C. quinquecarinata; P. jonesi, originally described in Anolis lionotus (syn. Norops oxylophus) from Nicaragua, inhabits N. oxylophus, N. biporcatus, and Basiliscus basiliscus; and the new species, which inhabits B. basiliscus. Parallopharynx matternae n. sp. differs from all other members of the genus by having a metraterm extending posteriad from the genital pore to the posterior margin of the ventral sucker, whereas in P. arctus and P. gonzalezi, the metraterm never surpasses the midlevel of the ventral sucker and in P. jonesi it never passes the anterior margin of the ventral sucker, and by having an oral sucker that does not exceed 150 microm in diameter with a subsequent greater oral-ventral sucker width ratio ranging from 1:0.88-1.12 (averaging 1:1), whereas values range from 1:0.71-0.83 for P. gonzalezi and P. arctus, and from 1:0.59-0.68 for P. jonesi. Parallopharynx spp. possesses Y-shaped excretory vesicles with a long central stem and short arms bifurcating immediately posterior to the ovary; similar to those found in members of the Telorchiidae. Additional similarities in the relative positions of the gonads and the structure of the cirrus sac and metraterm indicate a close relationship between Parallopharynx and members of the Telorchiidae.  相似文献   

2.
We propose Tinamutrema as a new genus for Brachylaima centrodes (Braun, 1901) Dollfus, 1935 and for T. canoae, as a new species inhabiting tinamus in the Area de Conservación Guanacaste, Costa Rica. Specimens from Costa Rica resemble B. centrodes in having an elongate body, pretesticular genital pore and terminal genitalia, intercecal uterine loops occupying all available space between the anterior testis and the intestinal bifurcation, an oral sucker width:pharynx width ratio of approximately 1:0.55, an oral sucker:ventral sucker width ratio of approximately 1:1, and vitelline follicles extending into the forebody closer to the pharynx than to the anterior margin of the ventral sucker and by living in the cloaca. They differ from B. centrodes in having vitelline follicles that do not extend as far anteriorly as those in B. centrodes, which extend anteriorly to the level of the anteriormost extent of the cecal "shoulders," dense tegumental spination as opposed to sparse or no spination, relatively smaller cirrus with fewer spines, longer and more sinous pars prostatica, and forebody averaging 36% of total body length (TBL) as opposed to 42% TBL. Both species differ from other members of the Brachylaimidae in possessing a spinose cirrus and a cirrus sac containing both the cirrus and the pars prostatica. Preliminary phylogenetic assessment suggests that these traits are plesiomorphic, and thus the species are basal to the rest of the Brachylaimidae, whose diagnosis we emend accordingly.  相似文献   

3.
A new species of digenean found in the intestines of the steely-vented hummingbird Amazilia saucerrottei and the yellow-olive flycatcher Tolmomyias sulphurescens from the Area de Conservación Guanacaste, Guanacaste, Costa Rica, resembles members of the Prosthogonimidae in having a highly lobate ovary; an elongate cirrus sac containing the cirrus, pars prostatica, and internal seminal vesicle; no external seminal vesicle; 2 fields of extracecal vitelline follicles restricted to the area between the intestinal bifurcation and testes; and uterine loops occupying all available space in the hind body. The new species differs from all other members of the family in having genital pores opening laterally to the cecum, immediately anterior to the acetabular level, and markedly oblique rather than symmetrical testes. Consequently, we propose the new genus Whallwachsia for the species. Preliminary phylogenetic assessment suggests that the species is the sister group of all other prosthogonimids.  相似文献   

4.
We describe 2 new species of leucochloridiid-like brachylaimoid digeneans parasitizing a variety of birds in the Area de Conservación Guanacaste, Costa Rica, each of which we assign to a new genus. According to Pojmanska's (Pojmanska, T. 2002a. Superfamily Brachylaimoidea Joyeux & Foley, 1930. In Keys to the Trematoda, D. I. Gibson, A. Jones, and R. A. Bray [eds.]. CAB International and The Natural History Museum, London, U.K., p. 31-36.) key for the Brachylaimoidea, we are unable to place either species in any family. One species most closely resembles members of Leucochloridium by having well-developed suckers, lacking an esophagus, and having cecal shoulders, gonads at the posterior end, and the genital pore at posterior end of body but differs by having symmetrical testes, a posttesticular ovary, and a terminal genital pore; thus, we propose the genus Bakkeius for it. The second new genus resembles members of Michajlovia by having ventral genital pores but differs by having extracecal uterine loops in the forebody, a cirrus sac containing the pars prostatica and seminal vesicle, and gland cells surrounding the genital pore; thus, we propose Pojmanskia for it. These new genera must currently be treated as incertae sedis according to Pojmanska (op. cit.); however, we feel that future phylogenetic analyses will require emendation of the family diagnosis for Leucochloridiidae to include those taxa with terminal and ventral genital pores and with preovarian testes.  相似文献   

5.
Specimens of a species of cyclocoelid digenean inhabiting Jacana spinosa from the Area de Conservación Guanacaste, Costa Rica, most closely resemble Haematotrephus facioi (Brenes and Arroyo, 1962) Yamaguti, 1971, in the same host from Aranjuez, Puntarenas Province, Costa Rica, in having confluent vitelline follicles posteriorly, diagnostic of Neohaematotrophus, and in pharynx length, ovary width, and cirrus sac on the sinistral side. The new species is also highly similar in appearance to H. gendrei Dubois, 1959, also inhabiting a jacanid (from West Africa), which has vitelline follicles confluent posteriorly, and extending anteriorly to the intestinal bifurcation and genital pore opening immediately posterior to the anterior margin of the pharynx. Like H. facioi, H. gendrei has a relatively much shorter and broader cirrus sac than does the new species. Examination of the holotype and paratype of H. facioi confirmed that the specimens from Guanacaste differ in having a longer body, a larger ovary and eggs, and smaller testes. They also have the ovary on the sinistral rather than the dextral side of the body, genital pore anterior to the pharynx rather than at or posterior to the level of the posterior margin of the pharynx, longer and thinner cirrus sac, and eggs without eyespotted miracidia. Half the eggs in both specimens of H. facioi have well-developed eyespotted miracidia, whereas the typical condition for cyclocoelids is for virtually all eggs to exhibit eyespotted miracidia. Both H. facioi and H. gendrei are transferred to Neohaematotrophus, along with the new species.  相似文献   

6.
A new species of allocreadiid digenean is described from Priapichthys annectens (Regan) (Osteichthyes: Poeciliidae) in the Area de Conservación Guanacaste, Costa Rica. A new genus, Paracreptotrema, is proposed to accommodate this species as well as Fellodistomum mendezi Songandares-Bernal, 1955, which was previously described from another poeciliid, Brachyrhaphis episcopi, in Panama. Paracreptotrema differs from all other nominal genera of Allocreadiidae by a combination of its symmetrical testes, restricted vitellaria, and the lack of oral lappets (muscular 'papillae') or other such appendages. Paracreptotrema blancoi n. sp. resembles Creptotrema creptotrema Travassos, Artigas and Pereira, 1928, but differs in lacking ventral oral lappets and in having vitellaria extending posteriorly only to the level of the testes. It can be distinguished from P. mendezi n. comb. in having a relatively larger and more posteriorly placed acetabulum, vitellaria that are more restricted anteriorly, smaller testes, and a uterus that does not extend to the posterior end of the body. The genus seems to be restricted to poeciliids in Central America.  相似文献   

7.
Wallinia chavarriae n. sp. is described from the small-bodied characids Astyanax aeneus and Bryconamericus scleroparius in the Area de Conservación Guanacaste, northwestern Costa Rica. The species differs from W. valenciae in possessing an acetabulum that is smaller than the oral sucker and vitelline follicles that are ovoid or rounded rather than elongate and tubular. Detailed comparison between these 2 species is handicapped by the less than satisfactory condition of the type and only museum specimen of W. valenciae. Wallinia chavarriae and W. valenciae belong to a subfamily of trematodes, Walliniinae, that arguably includes Creptotrematina spp., Magnivitellum simplex, and possibly Margotrema. The morphology of walliniines suggests that they are macroderoidids, but a clearer understanding of their classification could be gained from their larval morphology or from molecular systematic studies. The host associations of a monophyletic Walliniinae would indicate diversification within 2 groups of freshwater fishes: the neotropical characids for species of Wallinia, Creptotrematina, and Magnivitellum and the endemic central Mexican goodeids for those of Margotrema. The biogeography and host associations of these parasites provide a system for studies of potential host switching and vicariance, involving the middle-American and neotropical regions.  相似文献   

8.
A new species of Urotrema inhabits Norops oxylophus and Norops cupreus from the Area de Conservación Guanacaste, Costa Rica. The new species is most similar to Urotrema scabridum but differs by having a relatively longer esophagus, at least 10% of the total body length versus 4-8% in U. scabridum; an oral sucker width: ventral sucker width ratio less than 1 : 1 (averaging 1 : 0.76) versus 1 : 1 or greater; an oral sucker width : pharyngeal width ratio less than 1 : 0.5 (averaging 1 : 0.42) versus greater than 1 :0.5; and by having many transversely oriented posttesticular uterine loops versus a few vertically oriented posttesticular uterine loops.  相似文献   

9.
Summary Four new species of hystrignathid nematodes are described from the midgut caeca of Passalus unicornus (Coleoptera: Passalidae) from St. Lucia, West Indies. Artigasia horridospina n.sp. is differentiated from A. dispar van Waerebeke, 1973 by virtue of fewer rows of spines in the oesophageal region and in possessing lateral alae, and from A. insignia Travassos & Kloss, 1958 in the extent of the oesophageal spiens and in having the lateral alae commence more anteriorly. The first annule is also much shallower than that of A. insignia. Longior semialata n.sp. is differentiated from L. longicollis Travassos & Kloss, 1958 on body length, b ratio, egg size and the starting point of the lateral alae. Mentecle magnifica n.sp. differs from M. parvus Travassos & Kloss, 1958 in having the spines of the oesophageal region extending much further down the body and in having ridged eggs. It is also longer and relatively thinner. Paraxyo ensicrinatus n.sp. differs from P. monodelpho Travassos & Kloss, 1958 in having a proportionately longer tail. The spines in the oesophageal region also extend considerably further posteriorly than in P. monodelpho.Two types of male associated with the above nematodes are described and illustrated, but not assigned to females. Pulchrocephala? pulchrocephala Travassos, 1925 is redescribed from the gut of the mole-cricket Scapteriscus vicinus.Scanning electron micrographs of four of the described species are given and briefly discussed. ac]19801024  相似文献   

10.
Clitellocephalus americanus n. gen., n. sp. (Apicomplexa: Eugregarinida: Gregarinidae) is described from Cratacanthus dubius (Coleoptera: Carabidae) collected from Keith County in the Sandhills of western Nebraska. Clitellocephalus ophoni n. comb. is redescribed using original type material from Ophonus pubescens (Coleoptera: Carabidae) collected in Sète, France. Clitellocephalus n. gen. is distinguished by a deltoid epimerite with an internal anterior obconoid structure and a basal toroidal vacuole, which is retained in gamonts. Protomerites are broadly elliptical to cylindrical; deutomerites are narrowly obovate. Association is precocious, caudofrontal, and biassociative, with the satellite protomerite engulfing the posterior end of the primite deutomerite to form an interlock. Gametocysts are spherical. Sporoducts are present but reduced and irregular in number. Oocysts are dolioform, dehiscing in chains. The species described herein are differentiated by their overall size and relative proportion of cellular structures.  相似文献   

11.
The land snail family Odontostomidae has a poor fossil record, mainly from the middle Paleogene and early Neogene of Argentina. In this paper a new species of Odontostomidae from the Paleocene of Uruguay (Queguay Formation) is described. Bahiensis priscus n.?sp. represents the first record of the genus Bahiensis Jousseaume 1877, and the oldest record for an Odontostomidae. The new species is characterized by a pupoid fusiform shell and an oval aperture with a single axial columellar fold. Present distribution of the genus indicates a tropical?Csubtropical environment, in high humidity rate areas.  相似文献   

12.
Heterodera longicolla n. sp., a member of the H. goettingiana group, is described and illustrated from roots of buffalo-grass, Buchloë dactyloides (Nutt.) Engelm., in Manhattan, Kansas. This new abullate species, having second-stage larvae with only three lines in the lateral field, is most closely related to H. cyperi Golden, Rau & Cobb, 1962, but differs particularly in having a shorter stylet in larvae, males and females; in possessing only three annules on the head of larvae and males; in having a shorter tail in larvae; and by the presence on cysts of a small anus without a circum-anal pattern.  相似文献   

13.
The euglenoids are unicellular eukaryotic flagellates living in a diversity of soils and aquatic environments and ecosystems. This study describes the ultrastructure of an euglenoid isolated from the surface of a boiling mud pool with temperatures ranging from 38 to 98 degrees C and pH 2 - 4. The hot mud pool is located in Area de Pailas de Barro, Las Pailas, Rincón de la Vieja Volcano, Guanacaste, Costa Rica. The morphological characterization of the Euglena pailasensis was performed by SEM and TEM. It was determined that, although the euglenoid was obtained from an extreme volcanic environment, the general morphology corresponds to that of a typical member of Euglena of 30-45 microm long and 8-10 microm wide, with membrane, pellicle, chloroplasts, mitochondria, nucleus, pigments and other cytoplasmic organelles. E. pailasensis is delimited by a membrane and by 40 to 90 pellicle strips. It was observed up to 5 elongated chloroplasts per cell. The chloroplast contains several osmiophilic globules and a pyrenoid penetrated by few thylakoid pairs. The nutritious material is reserved in numerous small paramylon grains located at the center of the cell, mitocondria are characterized by the presence of crests in radial disposition toward the interior of the lumen. It was also observed around the external surface "pili" like filaments originating from the pellicle strips. There is no evidence for the presence of flagella in the ampulla (reservoir/canal area), a fact confirmed by negative staining, and a difference regarding other species of Euglena. The observed ultrastructural characteristics are not sufficient to explain the adaptation of this species to acid and hot environments.  相似文献   

14.
Bartolius pierrei n. g., n. sp. (Digenea: Gymnophallidae) is described from metacercariae and naturally and cultivated obtained adults from southern Argentina. The second intermediate host is Darina solenoides (King) (Bivalvia: Mactridae) and the definitive host is Larus dominicanus Lichtenstein (Aves: Laridae). The diagnostic characters are as follows: Body small, oval. Oral sucker without lateral projections, twice size of ventral sucker (except in young metacercariae). Caeca short (in adults), without dorsal diverticula. Ventral sucker in posterior third of body. Ventral pit absent. Seminal vesicle bipartite. Ovary post-testicular. Vitelline glands paired, compact, close to ventral sucker. Uterus in fore- and hindbody. Genital atrium tubular. Genital pore inconspicuous, close to anterior margin of ventral sucker. Excretory vesicle Y-shaped with very short stem. Excretory formula: 2[(2+2)+(2+2)]=16. Bartolius is distinguished from other genera of the Gymnophallidae by the post-testicular position of the ovary.  相似文献   

15.
Divisispiculimermis mirus n. gen., n. sp., a mermithid parasitizing larvae of Chironomus sp. in the Cajón o Grande Stream, Córdoba, Argentina, is described. The new genus differs from all other mermithid genera in having paired spicules which are separated and divided into proximal and distal sectors. The other diagnostic characters of the genus are medium size, nematodes with the cuticle appearing smooth (lacking cross fibers under the light microscope); head separated from the rest of the body by a slight constriction at the level of the amphids, six cephalic papillae, mouth papillae absent, mouth opening posterior to level of cephalic papillae; six hypodermal chords at midbody; weakly S-shaped vagina; postparasitic juvenile with a tail appendage.  相似文献   

16.
Cacatuocotyle paranaensis n. sp. (Dactylogyridae, Ancyrocephalinae) is described from the gills of the characid fishes Characidium lanei Travassos and C. pterostictum Gomes collected from two streams on the coast of the State of Paraná, Brazil. Cacatuocotyle n. g. is proposed for species possessing a single cephalic lobe (terminal), one pair of head organs, a convex haptor with thickened muscular anterior margins, one anchor-bar complex (ventral), seven pairs of ventral hooks (one pair associated with the anchor shafts; one central pair anterior to the bar; five submarginal bilateral pairs) and a sinistral vaginal aperture.  相似文献   

17.
A detailed examination (including scanning electron microscopy) of newly collected nematode specimens (subgravid females) referable to Philometroides caudatus Moravec, Scholz and Vivas-Rodríguez, 1995, from the swimbladder of the pimelodid catfish, Rhamdia guatemalensis, in the Papaloapan River in Tlacotalpan, State of Veracruz, Mexico, as well as the paratype specimens of this species, revealed the presence of a small buccal capsule armed with peribuccal teeth in the female. Because of this unique morphological feature within the Philometridae, and considering other taxonomically important characters such as the structure of the male tail and the shape of the anterior end of the esophagus in the gravid female, Neophilometroidinae n. subfam, and Neophilometroides n. gen. are proposed to accommodate this species. Philometra paraguayensis Petter, 1995, is transferred to Neophilometroides as N. paraguayensis (Petter, 1995) n. comb. Newly collected specimens are briefly described and illustrated.  相似文献   

18.
Four species of Procyrnea were collected in birds from the Area de Conservacion Guanacaste, Costa Rica. Procyrnea brevicaudata n. sp. in Crypturellus cinnamomeus resembles P. ficheuri, P. murrayi, P. ameerae, P. dollfusi, and P. aptera in lacking lateral alae but differs from all these species in having 2 longitudinal ridges on the left side of the body, in having a sinistral rather than ventral vulvar opening, and in having dorsally bent rather than straight female tails. Procyrnea mawsonae n. sp., in Buteo magnirostris, is similar to P. strialata in body size and in having 2 transverse striated lateral alae, but differs by having longer and differently shaped spicules, and by lacking a single preanal sessile papilla. Procyrnea mclennanae n. sp., in Heliomaster constantii, is similar to P. strialata (Zhang, 1991) and P. mawsonae n. sp. in having 2 transverse striated lateral alae, but it can be distinguished from P. strialata and P. mawsonae in having 4 rather than 3 small teeth on the interior border of the pseudolabia, in having unequal rather than equal lateral alae, and in having longer spicules. Procyrnea sp., on the basis of a single adult male in Campephilus guatemalensis, resembles P. suraiyae, P. tulostoma, and P. unilateralis in possessing a single and long lateral ala, but can be distinguished from P. suraiyae and P. tulostoma in the length of the left spicule, in the left spicule having a bifid distal end, the right spicule having a rounded distal end rather than both spicules having pointed distal ends, and in having the lateral ala beginning at the lip region instead of posterior to the cervical papillae. It differs from P. uncinipenis in having a spicule ratio of 1:3.5 rather than 1:2.5, in the left spicule having a bifid rather than alate distal end, and in the absence of a single preanal papilla.  相似文献   

19.
A hitherto unknown rotifer species was found in ponds of Doñana National Park (Spain) during winter 1990, 1991 and 1992. It belongs to the family Lecanidae (Monogononta), is related to Lecane ungulata and superficially resembles Lecane leontina.Two specimens of this species hatched after two days incubation of pond sediments in the laboratory.  相似文献   

20.
The following nomenclatural correction is made: a new combination, Eimeria chalcides (Probert, Roberts &; Wilson, 1988) for Tyzzeria chalcides Probert et al., 1988 from the ocellated skink Chalcides ocellatus. The sporulated oöcyst is redescribed and compared with other Eimeria spp. reported from the family Scincidae in order to verify the species. Oöcysts of E. chalcides are cylindrical, 35 × 18.6 (32–37 × 17–20.5) μm with a thin bi-layered wall; the shape-index (mean length/mean width) is 1.88. A micropyle, oöcyst residuum and polar granule are absent. The sporocysts are broadly ellipsoidal, 11.9 × 8.9 (8.5–13 × 7.5–11) μm and without a Stieda body; the shape index is 1.35.  相似文献   

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