Synopsis of the species of Thelohanellus Kudo, 1933 (Myxozoa: Myxosporea: Bivalvulida)

Abstract

A synopsis of the species of Thelohanellus Kudo, 1933 (Myxozoa: Myxosporea: Myxobolidae) is presented. It includes a total of 108 nominal species. For each species, the most relevant morphological and morphometric characteristics are provided, together with data on the type-host and locality, the site of infection within the host and the original references.

Thelohanellus wangi n. sp. (Myxozoa, Myxosporea), a new gill parasite of allogynogenetic gibel carp (Carassius auratus gibelio Bloch) in China, causing severe gill myxosporidiosis

“…According to Lom and Dyková (2006), the myxospores of Thelohanellus species are generally tear-shaped or pyriform to broadly ellipsoidal in valvular view and more slender in sutural view, with always smooth spore valves usually surrounded by a mucous envelop and a single pyriform or a tear-shaped polar capsule harboring a single coil of polar filament. Based on these taxonomic features, about 109 Thelohanellus species have so far been described worldwide, which indicates that Thelohanellus is the sixth most speciose myxozoan genus after Myxobolus, Myxidium, Henneguya, Ceratomyxa, and Chloromyxum (Abdel-Ghaffar et al 2013;Zhang et al 2013). The described species here completely conforms to the morphological definition of Thelohanellus genus but differ morphologically from all described species, including all gill-dwelling and gibel carp-infecting species (please see the species description in "Results" section and Table 1).…”

Histopathology of gill myxosporean infection in cultured Indian major and minor carps, West Bengal, India

“…Gills on both sides of the carp were removed with least damage and placed for examination in separate Petri dishes containing filtered water. The myxosporean identification was as per previous descriptions (Lom and Arthur, ; Kaur and Singh, ; Zhang et al., ). The parasitic frequency index (PFI) in percentage was calculated by taking the number of hosts infected by an individual parasite identified to genus level, against the total number of hosts examined.…”

Morphological, histopathological and molecular characterization of Thelohanellus muscularis n. sp. (Cnidaria: Myxosporea) infecting head muscles of Labeo rohita from Ranjit sagar wetland, Punjab (India)

“…The genus Thelohanellus Kudo, 1933 [1] is the sixth most speciose myxozoan after Myxobolus, Myxidium, Henneguya, Ceratomyxa and Chloromyxum with 108 nominal species [2]. Species belonging to Thelohanellus Kudo, 1933 are typically histozoic (rarely coelozoic) infecting almost every organ of the fish.…”

“…A single polar capsule is present, either pyriform or tear shaped [3]. Most of the species of Thelohanellus have been reported to be non pathogenic to their hosts, however, T. wuhanensis [4], T. hovorkai [5], T. nikolskii [6], T. kitauei [7], T. wangi [8], T. bifurcata [9], T. filli [10] have been shown to cause severe morbidity and mortality of infected fish [11][12][13][14]. Ranjit Sagar Wetland is located on river Ravi which is about 24 km upstream of Madhopur Headworks in Gurdaspur district, Punjab.…”