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1. A new genus and species of the Monticelliinae (Eucestoda: Proteocephalidea), a parasite of Pseudoplatystoma fasciatum (Pisces: Siluriformes) from the Paraná River basin (Argentina), with comments on microtriches of proteocephalideans

Creator:
Arredondo, Nathalia J., de Chambrier, Alain, and Gil de Pertierra, Alicia A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Cestoda, Proteocephalidea, taxonomy, morphology, barred sorubim, Pimelodidae, and South America
Language:
English
Description:
This paper describes Regoella brevis gen. n. et. sp. n. (Proteocephalidea: Monticelliinae), a parasite of the intestine of the barred sorubim Pseudoplatystoma fasciatum (Linnaeus) from the Paraná River basin. The new genus is placed in the Monticelliinae because of the cortical position of the genital organs. It differs from all known genera included in the Monticelliinae by the following combination of characters: 1) a quadrangular scolex with a truncated conical apex and formed by four lobes separated by grooves; 2) uniloculate suckers of inverted triangular shape possessing a small cone-shaped projection at each corner of the anterior margin; 3) strobila consisting of a low number of proglottides; 4) testes arranged in one dorsal field; 5) a cirrus-sac, which represents more than one half of the proglottis width, cirrus surrounded by conspicuous chromophilic gland cells; 6) a butterfly-shaped and strongly lobulate ovary; and 7) formation of uterus of type 2. The examination of the tegument surface with scanning electron microscopy revealed the occurrence of three types of microtriches: acicular and capilliform filitriches and gladiate spinitriches. The new species is the eighth proteocephalidean reported from P. fasciatum, six of which are commonly found in the Amazon and Paraná River basins.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. Description of a new flagellate protist Desmomonas prorhynchi gen. et sp. n. associated with problematical cell masses, parasitic in the turbellarian Prorhynchus sp. (Lecithoepitheliata)

Creator:
Williams, Joan B.
Format:
print
Type:
model:internalpart and TEXT
Subject:
parasitic flagellate, ultrastructure, Desmomonas prorhynchi sp. n., Lecithoepitheliata, Prorhynchus, desmosome, epicuticular projections, and mitochondrial derivative
Language:
English
Description:
The fine structure is described of a new nonphotosynthctic flagellate, named Desmomonas prorhynchi gen. et sp. n„ cndoparasitic in the lecilhoepilheliate turbellarian Prorhynchus sp. The flagellates surround cell masses enveloped by a protective wall, to which adhere many small, regularly arranged cylindroid bodies; these structures are reminiscent of epicuticular projections characterising the body walls of some oligochaetes and polychaetes. The cells of a cell mass arc joined to the enveloping wall by spot hemidesmosomes. Their cytoplasm contains Golgi systems, mitochondria, fibrillar dense bodies, paired centrioles, and rod-shaped bacteria. Certain cells possess four ccntrioles. Ü. prorhynchi bears two flagella, and is attached temporarily to a cell mass by an anterior process ending at a highly organised desmosome. The flagellate plasma membrane has a fuzzy coating. Hair-like plasmalcmmal extensions project from the base of the anterior process. A mitochondrial derivative containing dense spheres lies some distance from the flagellar basal bodies. There is no Golgi apparatus. Other cytoplasmic constituents of the flagellate morphology are vacuoles, and microneme-like bodies. The two flagella, similar and without paraxial rods, arise from a flagellar pocket; neither is recurrent. The new protist cannot at present be assigned to any existing zoomastigophorean order.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public