Hyalopsora tibetica Y.M. Liang & S.T. Liu, 2021

Wang, Lei, Liu, Shi-Tong, Liu, Yun & Liang, Ying-Mei, 2021, Two new species and one new record of Hyalopsora (Pucciniastraceae) on ferns in China, Phytotaxa 527 (1), pp. 41-50 : 45-46

Hyalopsora tibetica Y.M. Liang & S.T. Liu , sp. nov. ( Fig. 3 )

MycoBank no.: MB830424.

Holotype:— China, Tibet Prov., 29˚39’05”N, 94˚42’50”E, 3918 m asl, on Athyrium spinulosum (Athyriaceae) , 24 July 2016, Y. M. Liang, BJFC-R02435 .

Etymology:— Tibetica , referring to the place of collection.

Distribution:— China (Tibet Prov.).

Uredinia amphigenous, mostly on the abaxial surface of fronds, cauline, along the veins densely covering the whole frond, scattered or in groups, round or elliptical, yellow to golden-yellow, without paraphyses, 0.5–1 mm; fresh urediniospores and amphispores with yellow contents that fade over time. Urediniospores rare, elongate, ovoid, or sub-pyriform, 28.0–33.5 × 14.0–17.0 μm (x = 31.5 × 16.0 μm, n = 50), walls hyaline, 1.0–1.5 μm thick, finely echinulate, with 2–6 scattered germ pores. Amphispores abundant, near rectangular, rhombus, polygonal, sometimes very irregularly angular, 29.0–45.5 × 19.5–30.5 μm (x = 37.0 × 24.5 μm, n = 50), walls hyaline, 1.0–8.0 μm thick, 8 μm at the corners of the walls, not significantly thickened or only 1.0–2.0 μm thick in the remaining margins, nearly smooth, with 4–6(–7) scattered pores.

Additional specimen examined:— China, Tibet Prov., 29˚39’05” N, 94˚42’50” E, 3912 m asl, on Athyrium spinulosum (Athyriaceae) , 24 July 2016, Y. M. Liang, BJFC-R 02437.

Notes:— Hyalopsora tibetica resembles H. japonica and H. nodispora superficially in having amphispores that are larger than 35.0 μm. H. japonica and H. nodispora only have amphispores ( Chen 1982, Saba et al. 2012), while H. tibetica has urediniospores and amphispores in the same uredinia. H. tibetica is parasitic on Athyrium similar to H. pseudocystopteridis , H. hakodatensis and H. polypodii . However, H. pseudocystopteridis only possesses amphispores ( Wang et al. 1980).Although H. hakodatensis and H. polypodii have amphispores and urediniospores, their amphispores are smaller than those of H. tibetica . Those of H. hakodatensis are 15.0–30.0 × 12.5–20.0 μm, and those of H. polypodii 24.0–37.5 × 15.0–27.5 μm ( Kuprevich & Transhel 1957, Hiratsuka et al. 1992). In addition, H. tibetica can have up to 6 germ pores on urediniospores, whereas H. hakodatensis and H. polypodii have 4 or fewer germ pores. ( Sydow & Sydow 1914).

Figures

FIGURE 3—Hyalopsora tibetica (holotype, BJFC-R02435). A. Features of infected leaves. B. Vertical section of uredinium containing amphispores (A) and urediniospores (U). C. Urediniospores (U) and amphispores (A) D. Germ pores of amphispore. E. Germ pores of urediniospore. F. SEM of urediniospore. G. SEM of amphispore. Scale bars: B = 50 μm; C = 5 μm; D, E = 20 μm; F, G = 10 μm.