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Start Over Coverage 304-310

2. The life cycle of Dichelyne (Cucullanellus) minutus (Nematoda: Cucullanidae)

Creator:
Køie, Marianne
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Nematoda, Cucullanidae, Dichelyne (Cucullanellus) minutus, life cycle, flatfish, goby, and Nereis diversicolor
Language:
English
Description:
Mature specimens of the nematode Dichelyne (Cucullanellus) minutus (Rudolphi, 1819) (Ascaridida, Cucullanidae, Seuratoidea) were obtained from the intestine of flounder Platichthys flesus (L.) caught in the Øresund, Denmark. Plaice Pleuronectes platessa L. and common goby Pomatoschistus microps (Kröyer) also harbour this species. The eggs embryonate on the seabottom. Larvae about 440 µm long, and believed to be in their third stage, hatch from the eggs. These larvae are not directly infective to flounders or gobies. The polychaete Nereis diversicolor O.F. Müller acts as obligatory intermediate host. Experimental infections showed that larvae >600 µm long and provided with a chitinous tooth survived in flounder and common goby. The third-stage larvae moult to fourth-stage larvae in the fish gut wall. Mature worms occur in the lumen of the anterior part of the intestine. All developmental stages may be transferred from one flounder to another; thus the flounder may acquire the parasite also by devouring infected gobies.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Two new species of Myliocotyle (Monogenea: Monocotylidae) from the gills of Aetomylaeus maculatus and A. nichofii (Elasmobranchii: Myliobatidae) from Sarawak, Borneo, Malaysia

Creator:
Chisholm, Leslie A. and Whittington, Ian D.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Monogenea, Monocotylidae, Heterocotylinae, Myliocotyle, Myliobatidae, Aetomylaeus, and taxonomy
Language:
English
Description:
Myliocotyle borneoensis sp. n. and M. multicrista sp. n. (Monocotylidae: Heterocotylinae) are described from the gills of the mottled eagle ray, Aetomylaeus maculatus (Gray), and the banded eagle ray A. nichofii (Bloch et Schneider) (Myliobatidae), respectively, collected from the northern coast of Malaysian Borneo. These are the first monogeneans to be described on elasmobranchs from Borneo. The formerly monotypic Myliocotyle (for M. pteromylaei) was distinguished from other monocotylids by the distribution and morphology of the eight sclerotised dorsal haptoral accessory structures and the morphology of the male copulatory organ. However, we have determined that M. pteromylaei has ten structures on the dorsal surface of the haptor. Myliocotyle borneoensis is distinguished from M. pteromylaei by the morphology of the male copulatory organ and its accessory piece. Myliocotyle multicrista has 12 sclerotised dorsal haptoral accessory structures and a male copulatory organ with two accessory pieces. Additional sclerotised ridges across the ventral surfaces of each loculus (except the posterior-most pair) are also present in M. multicrista. The diagnosis for Myliocotyle is revised given our discovery of additional dorsal haptoral accessory structures in the type species and to accommodate other new characters of the two new species. Anterior secretions of Myliocotyle are discussed.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public