Morphological and molecular characterization of a new species of Isospora Schneider, 1881 (Apicomplexa: Eimeriidae) from the western wattlebird Anthochaera lunulata Gould in Western Australia

Morphological and molecular characterization of Isospora elliotae n. sp. (Apicomplexa: Eimeriidae) from the Australian magpie Gymnorhina tibicen (Latham, 1801) (Passeriformes: Artamidae) in Western Australia

A new coccidian species, Isospora elliotae n. sp., from the Australian magpie Gymnorhina tibicen (Latham, 1801) in Western Australia, is described and characterized morphologically and molecularly. Microscopic analysis of a faecal sample identified subspheroidal oocysts (n = 20), 20-22 × 18-20 (20.7 × 18.7); length/width (L/W) ratio 1.05-1.14 (1.10). Wall bi-layered, 1.0-1.3 (1.2) thick, outer layer smooth, c. 2/3 of total thickness. Micropyle and oocyst residuum absent, but usually two polar granules are present. Sporocysts (n = 28) ovoidal, 12-13 × 9-11 (12.6 × 9.7); L/W ratio 1.22-1.35 (1.30). Stieda body present, flattened to half-moon-shaped, c. 0.5 deep × 2.0 wide; sub-Stieda indistinct or barely discernible, c. 1.0 deep × 2.5 wide; para-Stieda body absent; sporocyst residuum present, composed of granules dispersed among the sporozoites. Sporozoites vermiform, with anterior and posterior refractile bodies and nucleus. Segments of three gene loci (18S rRNA, 28S rRNA and COI) were sequenced and I. elliotae n. sp. exhibited 99.8% genetic similarity to Isospora sp. MAH-2013a (KF648870) followed by 99.7% genetic similarity to Isospora neochmiae (Yang, Brice & Ryan, 2016) (KT224380) at the 18S rRNA gene locus. It shared 97.0% genetic similarity with an unnamed Isospora sp. (AY283852) at the 28S rRNA gene locus and it also shared the highest genetic similarity of 99.8% with the unnamed Isospora sp. from an American crow (OL999120) at the COI gene locus. Based on morphological and molecular data, this isolate is a new species named as I. elliotae n. sp.

Eimeria spp. and Tyzzeria perniciosa Allen, 1936 (Apicomplexa: Eimeriidae) from a Pacific black duck, Anas superciliosa Gmelin (Aves: Anseriformes), in western Australia

Four species of the Eimeriidae, Eimeria anatis Scholtyseck, 1955, Eimeria aythyae Farr, 1965, Eimeria krylovi Svanbaev & Rakhmatullina, 1967 and Tyzzeria perniciosa Allen, 1936, were morphologically identified from oöcysts recovered from a Pacific black duck, Anas superciliosa Gmelin. Additionally, genotypic characterization of E. anatis is provided via sequencing of the mitochondrial cytochrome c oxidase subunit 1 (cox1) and the small subunit ribosomal RNA (18S) genes. The four species are redescribed, providing additional morphological details. The validity of genera and coccidian species parasitizing birds of the order Anseriformes such as Wenyonella Hoare, 1933 and some Tyzzeria spp. are discussed. Molecular phylogenetic analyses for the cox1 and 18S rRNA genes resulted in monophylies of Eimeria spp. from Anseriformes which included the sequences obtained from E. anatis oöcysts.