Gymnosporangium przewalskii Y. M. Liang and B. Cao, 2017

Cao, Bin, Han, Fu-Zhong, Tian, Cheng-Ming & Liang, Ying-Mei, 2017, Gymnosporangium przewalskii sp. nov. (Pucciniales, Basidiomycota) from China and its life cycle, Phytotaxa 311 (1), pp. 67-76 : 71-72

Gymnosporangium przewalskii Y. M. Liang and B. Cao , sp. nov. ( Figs 3 , 4 )

MycoBank no.:—MB817891.

Holotype:— China, Qinghai Prov., 35°13′47″N, 101°56′48″E, 3020 m asl, on Juniperus przewalskii Komarov, Apr 4,

2014, F. Z. Han, BJFC-R 01859. (Isotype HMAS 247194).

Etymology:—The epithet “przewalskii ”, referring to the telial host “ Juniperus przewalskii ”.

Distribution:— China (Qinghai and Sichuan Prov.).

Hosts:—0, I on Sorbus koehneana C. K. Schneider ; III on Juniperus przewalskii .

Original description:—Spermogonia epiphyllous and globoid, subepidermal and in groups on discoloured spots,

type 4 of Cummins and Hiratsuka (2003). Aecia hypophyllous and fructicolous, 1–3 mm high, roestelioid. Peridium rupturing at apex but retaining tubular form. Peridial cells rhomboid, 39–96 × 13–27 μm (x = 64 × 21 μm, n = 50),

yellowish brown; outer walls smooth, inner walls moderately rugose with irregular blunt papillae, and side walls moderately rugose. Aeciospores globoid, minutely coronate, 18–30 × 15–27 μm (x = 25 × 21 μm, n = 50), yellow to yellowish-brown, wall 1–3 μm.

Telia caulicolous, on fusiform or irregular swelling with knotty rough surface, irregularly pulvinate, brown to black-brown, 3–10 mm across; teliospores two-celled, rarely one-celled, fusiform, more or less constricted at the septum, yellowish brown, 42–80 × 15–28 μm (x = 59 × 22 μm, n = 50), walls 0.5–2 μm; two pores near the septum in each cell; pedicels ≥ 200 μm long.

Additional specimens examined:— China, Qinghai Prov., 35°13′47″N, 101°56′48″E, 3020 m asl, on Juniperus przewalskii, Apr 4, 2014, F. Z. Han, BJFC-R01860 and BJFC-R01861 ; 35°12′32″N, 102°02′13″E, 2699 m asl, on Sorbus koehneana, Aug 15, 2015, B. Cao, BJFC-R02083 , BJFC-R02084 and BJFC-R02085 . Sichuan Prov., 32°54′33″N ,

103°40′59″E, 3225 m asl, on Juniperus przewalskii, Apr 23, 2015, B. Cao, BJFC-R 01911 and BJFC-R 01912.

Figures

FIGURE 3. Telial stage of Gymnosporangium przewalskii on Juniperus przewalskii (holotype, BJFC-R01859).A. Telia emerge from the branches in saffron yellow gelatinous form under moist conditions. B. Telia formed on a branch. C. An enlarged view of a telium. D, E. Teliospores. F. Teliospore with two septal germ pores in each cell (arrows). Scale bars: C = 2 mm; D, E, F = 20 μm.

FIGURE 4. Spermogonial and aecial stages of Gymnosporangium przewalskii on Sorbus koehneana (BJFC-R02083).A. Vertical section of a spermogonium.B.Aecia on the abaxial leaf surface. C.An enlarged view of aecia. D.Aeciospores. E. Surface structure of aeciospores. F. Minutely coronate processes on the aeciospores surface. G. Peridial cells. H. Moderately rugose processes on the inner wall of the peridial cells. I. Moderately rugose processes on the side wall of the peridial cells. Scale bars: A = 30 μm; B = 3 cm; C = 1 mm; D = 30 μm; E = 10 μm; F = 1 μm; G = 60 μm; H, I = 3 μm.