Cytological studies on three hymenolepidid species

Abstract

The karyotypes ofVampirolepis nana, Hymenolepis diminutaandVampirolepis erinacei(Cestoda: Cyclophyllidea) have been described. The number of chromosomes in the diploid cell of the studied taxa was 2n = 12. The absolute and the relative lengths of the chromosomes ofV. nanaandH. diminutawere measured. The chromosomes had similar metric values. In the karyotypes ofV. nanaandH. diminutathere were ten one-arm chromosomes and.one two-arm chromosome (the third in length in the karyotype ofV. nanaand the first in length in the karyotype ofH. diminuta). The chromosomes in the karyotype ofV. erinaceihad one arm which was proved by the terminal localization of the constitutive heterochromatin. The examined species differed in the morphology of some chromosomes in the karyotypes.

Classical and molecular cytogenetics of Khawia sinensis (Cestoda: Caryophyllidea), invasive parasite of carp, Cyprinus carpio

“…In general, the accumulation of a small amount of AT-rich DNA repeats primarily in the centromeric regions of almost all chromosomes is the most commonly reported feature in tapeworms (Rausch and Rausch 1990;Mutafova and Gergova 1994;Hanzelová et al 1995;Špakulová and Scholz 1999;Kráľová-Hromadová et al 2010;Orosová et al 2010a, b). In K. sinensis and K. saurogobii, small heterochromatin blocks were observed on all chromosomes, except for the biggest metacentric chromosome pair (present data, Orosová et al 2010a).…”

Diversity of Dilepididae (Cestoda: Cyclophyllidea) revealed by cytogenetic analysis

“…Because of the necessity to process living worms, karyological analyses are limited in studies on the taxonomy of cestodes. Small chromosomes and the scarcity of mitotic activity is another problem noted by the workers in the field (Wikgren & Gustafsson, 1965;Grey & Mackiewicz, 1974;Mutafova & Gergova, 1994). Chromosomal data for dilepidids are very limited.…”

“…Hymenolepis citelli and Vampirolepis erinacei possess telocentric chromosomes, H. diminuta is characterized by two first pairs of metacentric, three pairs of submetacentric and one, the last, pair of telocentric elements, V. nana possesses ten chromosomes with terminal localization of centromeres and two (pair no. 3) meta-submetacentrics, and the chromosomal complement of Rodentolepis straminea consists of two subtelocentric, two metacentric and two submetacentric pairs (Ward et al, 1981;Liu & Lin, 1987;Mutafova & Gergova, 1994;Špakulova & Casanova, 1998). The karyotype of M. crassiscolex is conspicuous by the presence of only biarmed, metacentric and submetacentric (pair no.…”

A cytogenetic study on the rodent tapewormRodentolepis myoxi

“…Conformally, all karyologically studied hymenolepidids except the genus Microsomacanthus possess six pairs of homologues (for review see Petkeviciute & Regel, 1994;Spakulova & Casanova, 1998). Characteristics of the chromosome morphology were revealed in only six species of the genus Hymenolepis s. l.: Rodentolepis microstoma (Profitt & Jones, 1969), Hymenolepis citelli (Ward et al, 1981), Hymenolepis diminuta (Liu & Lin, 1987;Mutafova & Gergova, 1994), Rodentolepis nana and Rodentolepis erinacei (Mutafova & Gergova, 1994) and Rodentolepis straminea (Spakulova & Casanova, 1998). The morphology of the chromosomes differed largely in individual species.…”

“…In fact, R. microstoma, H. citelli and R. erinacei were characterized by telocentric chromosomes. Rodentolepis nana from spontaneously infected mice and H. diminuta possessed five pairs of telocentrics and one pair of metasubmetacentric structure according to Mutafova & Gergova (1994). Interestingly, Liu & Lin (1987) reported a different morphology for the H. diminuta chromosome set with predominating meta-and submetacentric chromosomes.…”