Plasmodium paranucleophilum n. sp. from a South American Tanager*

Abstract

SYNOPSIS. The avian malaria parasite described in this paper was isolated from a South American tanager of uncertain species, somewhat tentatively identified as belonging to the genus Tachyphonus. It is believed to have come from northern Brazil. Because the erythrocytic stages are, except for minor differences, similar to those of Plasmodium nucleophilum it is proposed to call it P. paranucleophilum. The chief difference separating the 2 species is the appearance of phanerozoites of the new species in lymphocytes of the circulating blood; these are characteristically vacuolated and give rise to moderate numbers of merozoites, probably in most cases 50 or less. Strains of P. nucleophilum isolated from other passerine birds also produce phanerozoites parasitizing lymphocytes, but such cells have never been observed in the blood stream. A subspecies, P. nucleophilum toucani, which we isolated from a Swainson's toucan Ramphastos swainsonii, also produces phanerozoites invading lymphocytes but it is less selective; endothelial cells of the brain are heavily attacked. It is also very lethal to canaries, whereas passerine strains of P. nucleophilum are usually quite benign. P. paranucleophilum, if the strain we have isolated is typical, lies between the 2 in pathogenicity, causing marked anemia but seldom death.

Experimental study of newly described avian malaria parasite Plasmodium (Novyella) collidatum n. sp., genetic lineage pFANTAIL01 obtained from South Asian migrant bird

“…On the other hand, Palinauskas et al [9] showed that during single infection with low parasitemia (less than 1%) by Hu a subgenus parasite Plasmodium elongatum (pERIRUB01), hematocrit value in experimentally infected siskins decrease dramatically. The similar situation was observed in canaries experimentally infected with Novyella species P. paranucleophilum, the bone marrow of infected birds had heavy invasion at low parasitemia but anemia was clearly manifested by the decrease in hematocrit values [57]. Apparently, a huge infestation of bone marrow by phanerozoites reduces erythropoiesis and cause the decrease in the number of RBCs and therefore decrease hematocrit values.…”

“…Nucleophilic stages developing in the blood of the infected host allows to discriminate this species from other nonnucleophilic species of Novyella.This parasite can be readily distinguished from all nucleophilic Novyella species due to the following morphological characteristic of its mature gametocytes: i) the cytoplasm consists of intermediated readily visible large pale-stained and dense-stained areas, providing markedly heterogeneous appearance, ii) the majority of advanced gametocytes possesses the markedly indented (lobular-like) appearance of pellicle and iii) macro-and microgametocytes are di cult to distinguish based on their size and morphology of their nuclei. Additionally, the presence of a relatively large loose group on small pigment granules is also helpful during this parasite identi cation (see our description and [12,13,55,56,57]). The described parasite morphologically is the most similar to P. delichoni however, some features, like small roundish granules clearly distinguish this parasite from P. delichoni.…”

“…The exoerythrocytic stages were described in Plasmodium nucleophilum toucani with huge infestation of internal organs with phanerozoites and caused mortality in experimentally infected canaries [62]. Phanerozoites were also seen in different internal organs of birds infected by P. vaughani [4], P. paranucleophilum [57] and P. bertii [4].…”

Keys to the avian malaria parasites

“…5 k) ……………………………………………. P. paranucleophilum [ 8 , 113 ] 32 (4) Trophozoites and (or) binuclear meronts often produce clearly defined long outgrowths (Fig. 5 a); the outgrowths exceed the main body of the trophozoites in length 33 (34) One or two refractive globules present in advanced trophozoites and developing and mature meronts.…”

Blood parasites infecting the Hoatzin (Opisthocomus hoazin), a unique neotropical folivorous bird

“…Given the lack of gametocyte data, it is possible that the Plasmodium infections in these two Hoatzin individuals were abortive, but the fact that the two individuals (caught together) were infected with the same parasite suggests that its transmission is occurring, and the parasite lineage is circulating in Cojedes State, Venezuela. Tostes et al (2017) re-described the parasite linked to this cytb lineage as Plasmodium ( Novyella ) paranucloephilum , a species originally described by Manwell & Sessler (1971) in a South American tanager of uncertain species likely from northern Brazil. However, given the absence of morphological data in this study, and that there is no cytb neither other mtDNA genome sequences belonging to the original parasite description, we consider that it is premature to identify the lineage found in this study as P. paranucloephilum .…”