Developing an Apicomplexan DNA Barcoding System to Detect Blood Parasites of Small Coral Reef Fishes

Abstract

SUPPLEMENT Remarks Haemohormidium-like infectionsThe Haemohormidium-like species reported here from the Caribbean fishes all had division stages alike to those described infecting fishes of the Red Sea and the GBR, Australia, by firstly Saunders (1960) and Burreson (1989) Haemohormidium-like species and a haemogregarine, which we would agree with, particularly since we discovered pure infections of the former parasite with no haemogregarine stages present. Smit et al. (2006) described a Haemohormidium-like species parasitising both Chlorurus sordidus and Scarus psittacus (both Scaridae), the stages of their parasite all almost always in division. These stages were alike to the slender stages undergoing division described in the present study, those of Smit et al.(2006) measuring 7 x 1.9 µm and thus only slightly longer and wider than those described here.

Phylogenetic analysis of apicomplexan parasites infecting commercially valuable species from the North-East Atlantic reveals high levels of diversity and insights into the evolution of the group

“…The work of Janouškovec et al [ 4 ] highlighted the understudied nature of marine and freshwater environments in terms of the Apicomplexa and other related parasites. In the present study, the parasites found in Solea senegalensis and Pagrus caeruleostictus were close relatives of an apicomplexan from the blood of a Caribbean fish ( Ophioblennius macclurei , see [ 13 ]) and also of a parasite sequenced from an eDNA seawater sample from the Caribbean [ 54 ]. These sequences were in turn sister to an unnamed clade composed of parasites recovered from the mucous of several Caribbean corals (see the supplementary material in [ 4 ]).…”

“…[ 55 ]). Lastly, a set of sequences were placed in an unknown group of the Apicomplexa so far only recovered from the Caribbean Sea, having been found in the mucus of corals [ 4 ], an environmental sample from the water column [ 54 ], and a fish [ 13 ]. Additionally, our phylogenetic results suggest that the Apicomplexa recovered from elasmobranchs are basal, which is in line with the host’s phylogenetic relationships since elasmobranchs (together with the holocephalans) are the oldest jawed vertebrates on earth (e.g.…”

The distribution and host-association of a haemoparasite of damselfishes (Pomacentridae) from the eastern Caribbean based on a combination of morphology and 18S rDNA sequences

“…However, variation among Stegastes and apparent absence in A. saxatilis may have been attributable to small sample sizes and/or sampling from a single site. In a subsequent study, Renoux et al (2017) developed an apicomplexan DNA barcoding system, targeting the 18S rDNA gene, to detect infections of the Haemohormidium -like parasites in Stegastes spp. Phylogenetic analysis of this parasite by Renoux et al (2017) placed it at the base of a major monophyletic clade containing species of coccidia, suggesting it to be more closely related to this group than to the pirosplasms, the group to which the Haemohormidiidae have been assigned pending molecular support (see O'Donoghue, 2017 ).…”

“…In a subsequent study, Renoux et al (2017) developed an apicomplexan DNA barcoding system, targeting the 18S rDNA gene, to detect infections of the Haemohormidium -like parasites in Stegastes spp. Phylogenetic analysis of this parasite by Renoux et al (2017) placed it at the base of a major monophyletic clade containing species of coccidia, suggesting it to be more closely related to this group than to the pirosplasms, the group to which the Haemohormidiidae have been assigned pending molecular support (see O'Donoghue, 2017 ). As a follow-up to the work of Cook et al (2015) and Renoux et al (2017) , the aim of the current study was to determine the geographic distribution and host-association of this parasite in damselfishes in the eastern Caribbean.…”

“…Phylogenetic analysis of this parasite by Renoux et al (2017) placed it at the base of a major monophyletic clade containing species of coccidia, suggesting it to be more closely related to this group than to the pirosplasms, the group to which the Haemohormidiidae have been assigned pending molecular support (see O'Donoghue, 2017 ). As a follow-up to the work of Cook et al (2015) and Renoux et al (2017) , the aim of the current study was to determine the geographic distribution and host-association of this parasite in damselfishes in the eastern Caribbean. Specifically, we: 1) further quantify which damselfish species and life history stages are infected by the Haemohormidium -like blood parasite, increasing the sample size for under-sampled species and including juvenile life history stages; and 2) further elucidate the geographic distribution and phylogenetic affiliation of this blood parasite in the eastern Caribbean.…”