Rust Fungi of Southeast Asia

Crossopsora malloti (Racib.) Cummins

Description
Uredinia on fruit and both leaf surfaces, suprastomatal, erumpent, round, less than 5 mm, yellow to yellowish brown; paraphyses septate, peripheral, clavate to incurved, subhyaline to yellowish brown, 50-66 × 9-12 µm; wall dorsally thickened up to 2 µm.

Urediniospores globose, subglobose to obovoid, apex obtuse, hyaline, 18-27 × 17-20 µm; wall 1-2 µm thick, echinulate.

Specimens cited in description:
- BRIP 57423, 57486

Hosts
Host family:
- Euphorbiaceae

Host species:
- Melanolepis multiglandulosa

Distribution
Philippines

Comments
The urediniospores are smaller than described by Raciborski (1900) (36-47 x 25-34). Sydow and Petrak (1931) also found smaller urediniospores in the Philippine specimens of Crossopsora malloti (as Cronartium malloti).

Highslide JS
Crossopsora malloti on Melanolepis multiglandulosa - BRIP 57423.
Highslide JS
Crossopsora malloti on Melanolepis multiglandulosa - BRIP 57423.
Scale bar = 1 cm.
Highslide JS
Paraphyses of Crossopsora malloti on Melanolepis multiglandulosa - BRIP 57486..
Scale bar = 10 µm.
Highslide JS
Urediniospores of Crossopsora malloti on Melanolepis multiglandulosa - BRIP 57486.
Scale bar = 10 µm.