Rust Fungi of Southeast Asia

Phakopsora cingens Y. Ono.

Synonyms
Bubakia cingens (Syd. & P. Syd.) S. Ito
Melampsora cingens Syd. & P. Syd.
Physopella cingens (Syd. & P. Syd.) Ramachar & Bhagyan.
Schroeteriaster cingens (Syd. & P. Syd.) Syd. & P. Syd.

Description
Uredinia on lower leaf surface, subepidermal, erumpent, round to ellipsoidal, up to 400 µm, yellow to yellowish brown.

Urediniospores obovoid, apex obtuse, yellowish brown, 35-41 × 23-30 µm; wall 1.5-3 µm thick at sides, apex 3-8 µm thick, echinulate, with 4 germ pores.

Telia on lower leaf surface, subepidermal, forming crust, linear, confluent up to 400 µm, black.

Teliospores subglobose to ellipsoidal, apex rounded, 4 or more celled, reddish brown, 20-28 × 16-22 µm; wall 1.5-2.5 µm thick, 3-6 µm thick in upper layer of telium, smooth, in adherent crusts.

Specimens cited in description:
- BRIP 57465, 58383, 58390, 58406

Hosts
Host family:
- Phyllanthaceae

Host species:
- Bridelia ovata
- Bridelia stipularis

Distribution
Philippines, Vietnam

Comments
Unpublished molecular data indicates there is intraspecific diversity between specimens identified as Phakopsora cingens from Australia, Philippines and Vietnam. Phakopsora cingens was described from the Philippines by Sydow and Sydow (1911) as Melampsora cingens.

Highslide JS
Phakopsora cingens on Bridelia stipularis - BRIP 57465.
Highslide JS
Phakopsora cingens on Bridelia sp. - BRIP 58390.
Scale bar = 5 mm.
Highslide JS
Urediniospores of Phakopsora cingens on Bridelia stipularis - BRIP 57465.
Scale bar = 10 µm.
Highslide JS
Teliospores of Phakopsora cingens on Bridelia sp. - BRIP 58390.
Scale bar = 10 µm.