Table 1 Morphological characters, character states, and hosts for aphelid taxa

Aphelidium: Aph. chaetophorae

2.7–3, spherical

9

not observed

not observed

Chaetophora elegans

Aph. chlorococcorum f. chlorococcorum

1.5–2, “stiletto” pseudopodia

8

sessile or short stalk

7–13 × 5–6.5, ellipsoidal

Scenedesmus, chlorococcus algae (green algae)

Aph. chlorococcorum f. majus

2–3, spherical, conic “stiletto” anterior pseudopodium

14

stalked

5 × 8, ellipsoidal

Kirchneriella obesa, Ankistrodesmus (green algae)

Aph. deformans

2-3, spherical

unknown

not observed

12–30 diam, round to oval

Coleochaete soluta (green alga)

Aph. desmodesmi

~2, spherical, sub-spherical, angular numerous thin filopodia

~ 6

stalked

not observed

Desmodesmus opoliensis (green alga)

Aph. melosirae

4 × 6, pleomorphic

~ 10

sessile

12–14 × 10, oval

Melosira varians (diatom)

Aph. tribonematis

2–3, oval, numerous filopodia

6–8

sessile or short stalk

6–7, spherical, residual body outside

Tribonema gayanum, Botridiopsis intercedens (yellow-green algae)

Paraphelidium: Pa. letcheri

2–2.5, spherical, With a lamellipodium and subfilopodia

8–10

sessile or short stalk

6–8, spherical, single wall, residual body outside

Tribonema gayanum

Pa. tribonematis

2–2.5, oval, a broad anterior lamellipodium; a few lateral and anterior subfilopodia

~ 7

stalked

8–10, ellipsoid, two-walled, residual bodies between the two walls

Tribonema gayanum

Amoeboaphelidium: Am. achnanthis

~2 long

unknown

unknown

unknown

Achnanthes lanceolata (diatom)

Am. chlorellavorum

1–2, amoeboid

unknown

sessile

3–7, spherical

Chlorella spp. (green alga)

Am. occidentale

1.3–2.7, spherical, sub-spherical, elongate

7–10

stalked

unknown

Scenedesmus dimorphus

Am. protococcorum

2–4, spherical to elongate, numerous pseudopodia, thin trichipodia, thick lobopodia

~ 7

sessile

4–6 × 5–7, oval

Scenedesmus, Protococcus, chlorococcus algae

Am. radiatum

1–3, spherical, numerous filopodia

unknown

stalked

unknown

Kirchneriella, Ankistrodesmus, chlorococcus algae

Pseudaphelidium: Ps. drebesii

3 × 5, elongate

15

sessile

unknown

Thalassiosira punctigera (marine diatom)