Premium
Napamichum cellatum N. Sp. (Microspora, Thelohaniidae), a New Parasite of Midge Larvae of the Genus Endochironomus (Diptera, Chironomidae) in Sweden
Author(s) -
BYLÉN EVA K. C.,
LARSSON J. I. RONNY
Publication year - 1994
Publication title -
journal of eukaryotic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.067
H-Index - 77
eISSN - 1550-7408
pISSN - 1066-5234
DOI - 10.1111/j.1550-7408.1994.tb06041.x
Subject(s) - polar filament , microspora , biology , microsporidia , spore , ultrastructure , parasite hosting , zoology , anatomy , sporogenesis , botany , microspore , world wide web , computer science , pollen , stamen
The new microsporidium, Napamichum cellatum , a parasite of the adipose tissue of midge larva of the genus Endochironomus in Sweden, is described based on light microscopic and ultrastructural characteristics. Plurinucleate Plasmodia with nuclei arranged as diplokarya divide, probably by plasmotomy, producing a small number of diplokaryotic merozoites. The number of merogonial cycles is unknown. Each diplokaryotic sporont yields eight monokaryotic sporoblasts in a thin‐walled, more or less fusiform sporophorous vesicle. A small number of multisporoblastic sporophorous vesicles were observed, in which a part of the sporoblasts were anomalous. The sporogony probably begins with a meiotic division. The mature spores are slightly pyriform. Fixed and stained spores measure 2.1‐2.4 × 3.7‐4.5 μm. The five‐layered spore wall is of the Napamichum type. The polar filament is anisofilar with seven to eight coils (142‐156 and 120 nm wide). The angle of tilt is 55‐65°. The polaroplast has an anterior lamellar and a posterior tubular part. The granular, tubular and crystal‐like inclusions of the episporontal space disappear more or less completely when the spores mature. The crystal‐like inclusions are prominent in haematoxylin staining, but not visible with the Giemsa technique. The microsporidium is compared to other octosporoblastic microsporidia of midge larva and to the species of the genera Chapmanium and Napamichum.