world of amoeboid organisms

Vernalophrys algivore
(A) A Scenedesmus cell (arrow) is engulfed by a trophozoite. (B) Several Scenedesmus cells adhere to the surface of a plasmodium that has numerous vacuoles (arrow) in the cytoplasm. (C) One Scenedesmus cell (arrow) is ingested by an early-stage digestive cyst (From Gong, Patterson, and Hu, 2015).

Genus Vernalophrys Gong, Patterson and Hu, 2015

Diagnosis: Limnetic vampyrellid amoeba feeding by engulfment of unicellular chlorophycean algae (e.g., Scenedesmus dimorphus). It can exist as a trophozoite, plasmodium, digestive cyst, and resting cyst. The trophozoite predominantly exhibits an expanded fan-shaped appearance, with thin, tapering filopodia originating from the frontal or frontolateral hyaline fringe of the cytoplasm. Trophozoites, plasmodia, and digestive cysts can aggregate to form flocs.

Remarks: On the basis of the SSU rDNA gene sequence, this vampyrellid has closer affinities to Leptophrys, Platyreta, and other leptophryids than to the family Vampyrellidae; however, it has two distinctive regions in helix E10_1 (nucleotides 117 to 119; CAA) and E23_1 (nucleotides 522 to 523; AG) that made it different from the known leptophryids. The type strain was isolated from cultivation of Scenedesmus in both raceway ponds and flat-panel photobioreactors in Mesa, Arizona, USA.
ZooBank identifier: urn:lsid:zoobank.org:act: 949CB818-B9E4-4B

Vernalophrys algivore Gong, Patterson and Hu, 2015

Diagnosis: as for the genus. Trophozoites 10 to 30 µm, plasmodia 20 to 300 µm, digestive cysts 30 to 100 µm, and resting cysts 20 to 35 µm long.
ZooBank I: urn:lsid:zoobank.org:act:7C1C1087-D658-423A-A260- 0E8253AABEA9

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