During a survey the occurrence of Kudoa quraishii Mansour, Harrath, Abd-Elkader, Alwasel, Abdel-Baki et Al Omar, 2014, recently identified in the muscles of the Indian mackerel, Rastrelliger kanagurta (Cuvier), a species of Kudoa Meglitsch, 1947 infecting oocytes of mature females of the same host fish was found. The new species, for which the name Kudoa saudiensis sp. n. is proposed, infects oocytes that are enlarged with a whitish colour. The parasite develops in vesicular polysporous plasmodia within the oocyte. Infection occurs with a mean prevalence of 20% (7/35) of examined females. Mature spores are quadratic in shape in apical view, having four equal valves and four symmetrical polar capsules. Fresh spores are 2.4-3.6 µm long (mean ± SD 3.1 ± 0.3 µm), 4.3-5.4 µm (4.7 ± 0.3 µm) wide and 3.4-4.3 µm (3.8 ± 0.3 µm) in thickness and long. The smaller size of the new Kudoa species was the distinctive feature that separates it from all previously described species. Molecular analysis based on the SSU rDNA sequences shows that the highest percentage of similarity of 98.5% was observed with K. ovivora Swearer et Robertson, 1999, reported from oocytes of labroid fish from the Caribbean coasts of Panama. The percentage of similarity was 98% with K. azevedoi Mansour, Thabet, Chourabi, Harrath, Gtari, Al Omar et Ben Hassine, 2013 and 89% with K. quraishii. Phylogenetic analysis of the SSU and LSU rDNA data revealed a consistent of the new species with K. azevedoi and K. ovivora. Our findings support the creation of Kudoa saudiensis sp. n. that infects oocytes of the Indian mackerel Rastrelliger kanagurta., Lamjed Mansour, Abdel Halim Harrath, Abdel-Azeem S. Abdel-Baki, Saleh Alwasel, Saleh Al-Quraishy, Suliman Y. Al Omar., and Obsahuje bibliografii
Four new species of Ceratomyxa Thélohan, 1892 are described from the gall bladders of fishes collected off Lizard Island, Australia. These species are characterised using a combination of morphometric and molecular data. Ceratomyxa bartholomewae sp. n. is described from Hyporhamphus dussumieri (Valenciennes) (family Hemirhamphidae); C. koieae sp. n. is described from Sphyraena forsteri Cuvier (family Sphyraenidae); C. pantherini sp. n. is described from Bothus pantherinus (Rüppell) (family Bothidae) and C. reidi sp. n. is described from Chaetodon vagabundus Linnaeus (family Chaetodontidae). A fifth species from Zebrasoma veliferum (Bloch) (family Acanthuridae) is also reported but due to limited material is not formally described here.