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12. Pseudorhabdosynochus capurroi sp. n. (Monogenea: Diplectanidae) from the gills of Mycteroperca bonaci (Pisces: Serranidae) of the Yucatan Peninsula, Mexico
- Creator:
- Vidal-Martinez, Victor M. and Mendoza-Franco, Edgar F.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Monogenea, Diplectanidae, Serranidae, Mycteroperca bonaci, Peninsula of Yucatan, and Southern Mexico
- Language:
- English
- Description:
- A new monogcncan species, Pseudorhabdosynochus capurroi sp. n., is described from the gills of the black grouper, Mycteroperca bonaci (Poey) (Serranidae), from the Yucatan Peninsula, Mexico. The new species can be differentiated from all other known species of Pseudorhabdosynochus Yamaguti, 1958 by being the largest one recorded until now (1162-1535 pm body length). Moreover, the vagina of P. capurroi has a small funnel-shaped opening with a non sclerotized vesicle from which a fine sclerotized duct leads proximally to a sclerotized seminal receptacle, and the testis is bilobate. The squamodiscs have 14 to 16 rows of rods, of which 3 to 5 rows are closed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
13. Pseudorhabdosynochus yucatanensis sp. n. (Monogenea: Diplectanidae) from the gills of the red grouper Epinephelus morio (Pisces: Serranidae) of the Yucatan Peninsula, Mexico
- Creator:
- Vidal-Martinez, Victor M., Aguirre-Macedo, Leopoldina, and Mendoza-Franco, Edgar
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Monogenea, distribution, prevalence, abundance, red grouper, Yucatan Peninsula, and southeastern Mexico
- Language:
- English
- Description:
- Pseudarhahdttsynachus yucatanensis sp. n. (Diplectanidae) is described from the gills of the red grouper, Epinephelus maria (Valenciennes, 1824) (Serranidae), from the coast of the Yucatan Peninsula, Mexico. This new species is characterized by having both the ventral and the dorsal squamodiscs composed of 10-12 rows of rods, with 0-1 innermost row forming a closed circle. Furthermore, the vagina of P. yucatanensis has a non-sclerotized ampulla with a fine, sclerotized duct leading to a sclerot-ized seminal receptacle. Prevalence (percentage of infected fish) and abundance (mean number of worms per examined fish) were estimated for P. yucatanensis from 8 localities along the coast of Yucatan. Prevalence varies from 38% to 100%, while abundance was between 1.2 ± 0.6 and 43.2 ± 17.8 worms per ftsh. The lack of linear relationship between the host length and the number of monogcneans per fish (regression F, = 0.56. p = 0.45) was probably due to the fact that the sample was restricted to juvenile hosts.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14. Sciadicleithrum meekii sp. n. (Monogenea: Ancyrocephalinae) from the gills of Cichlasoma meeki (Pisces: Cichlidae) from cenotes (= sinkholes) of the Yucatan Peninsula, Mexico
- Creator:
- Mendoza-Franco, Edgar F., Scholz, Tomáš, and Vidal-Martinez, Victor M.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Sciadicleithrum meekii sp. n., Cichlasoma meeki, Monogenea, cenotes, and Mexico
- Language:
- English
- Description:
- Sciadicleithrum meekii sp. n. is described from the gills of the cichlid fish Cichlasoma meeki (Brind) from cenotes (= sinkholes) of the Yucatan Peninsula, Mcxico.The new species differs from congeners by having a dorsal hamuli with a prominent superficial root articulated with a straight shaft and curved point, and a vagina with a coiled tube comprised of one ring.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
15. The nervous system of Polystoma indicum (Monogenea: Polystomatidae) as revealed by nonspecific esterase localization
- Creator:
- Dutta, M. and Tandon, V.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Polystoma indicum, Polystomatida, Monogenea, nervous system, and nonspecific esterases
- Language:
- English
- Description:
- Using the localization of nonspecific esterases, the nervous system of Polystoma indicum Diengdoh et Tandon, 1991 could be revealed in toto. The nervous system is bilaterally symmetrical. Cerebral ganglia, which are connected by a thick dorsal commissure, are present dorsal to the pharynx. From the cerebral ganglia arise five anterior pairs and four posterior pairs of nerve trunks. The anterior nerves and/or their fine branches join to form a conspicuous circumoral nerve ring complex. The posterior nerves unite in the opisthaptoral region to form two main haptoral nerves, the branches from which innervate the components of the opisthaptor. Presence of nerve cells is also revealed in association with the main nerves, more predominantly in the vicinity of the opisthaptoral suckers.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
16. Transmission of the monogenean Gyrodactylus salaris
- Creator:
- Soleng, Arnulf, Jansen, Peder A., and Bakke, Tor A.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Gyrodactylus salaris, Monogenea, temperature, transmission, and Salmo salar
- Language:
- English
- Description:
- The present study is focusing on the transmission of the monogenean ectoparasite Gyrodactylus salaris Malmberg, 1957, a major pathogen on natural populations of Norwegian Atlantic salmon, Salmo salar L. In laboratory experiments the transmission rate of G. salaris after direct host to host contact was positively correlated with water temperature (1.2, 4,7 and 12.2°C). The transmission of detached G. salaris in the planktonie drift was studied in field experiments where salmon parr were individually isolated for 24 hours in small wire mesh cages suspended in the water column. Ten out of 157 salmon parr (prevalence 6.4%, mean intensity 1.0) contracted G. salaris infections after this exposure. Furthermore, 200 uninfected marked salmon parr were released into the same area of the river. After 24 and 48 hours, respectively 18 and 19 marked parr were caught by electro-fishing. The prevalence of G. salaris was 44.4% (mean intensity 1.9) after 24 hours, rising to 57.9% (mean intensity 2.3) after 48 hours. Gyrodactylids have no specific transmission stage or swimming ability, but detached G. salaris drifting in the water column were found to infect salmon parr. However, the transmission rate was markedly higher to free-living fish, suggesting that transmission routes such as indirect transmission from the substrate or direct contact transmission from infected live and/or dead fish, are relatively more important than transmission by drifting detached parasites.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
17. Ultrastructure of the buccal complex of Pricea multae (Monogenea: Polyopisthocotylea, Gastrocotylidae)
- Creator:
- Rohde, Klaus and Watson, Nikki A.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Pricea multae, Monogenea, ultrastructure, buccal complex, oral sucker, receptors, and taste organ
- Language:
- English
- Description:
- The ‘buccal complex’ of Pricea multae Chauhan, 1945 consists of two buccal suckers, the pharynx, a putative taste organ and the mouth cavity. The two suckers are dorsal to the mouth cavity, and the pharynx posterior to them. The septum in each sucker consists of connective tissue containing muscle filaments, lined by tegument with short irregular microvilli. The mouth cavity and the lumen of the suckers are lined by tegument with short irregular lamellae and by tegument with long bulbous, interconnected lamellae, separated from each other and from the body surface tegument by septate junctions. A ventral extension of the mouth cavity is also lined by tegument with short irregular lamellae. An anterior ‘taste organ’ is lined by ‘normal’ (body) tegument and tegument with short irregular lamellae. Glandular ducts open into it, and it contains many small uni-ciliate and multiciliate receptors, as well as two receptor complexes each consisting of a large non-ciliate receptor surrounded by small and large uniciliate receptors, with multiciliate receptors closeby. The four types of receptors are described in detail. The anterior part of the pharyngeal lumen is lined by an epithelium with dense surface lamellae and is penetrated by non-ciliate receptors. Attention is drawn to significant differences between the buccal complexes of the polyopisthocotylean monogeneans Pricea multae (Gastrocotylidae), Gotocotyla secunda (Tripartii, 1956) (Gastrocotylidae), Pulylabroides australis (Murray, 1931) (Microcotylidae), Zeuxapia serialae (Meserve, 1938) (Axinidae) and Diclidophora merlangi (Kuhn, 1832) (Diclidophoridae).
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public