Misidentification of Urocystis species on Ceratocephala falcata (Ranunculaceae) from Northern Iran

Roumi and Sharzei (2017) recently reported the occurrence of Urocystis eranthidis (Pass.) Ainsw & Sampson in Iran based on the study of an infected specimen of Ceratocephala falcata (L.) Cramer (Ranunculus falcatus L.) collected from Maragheh, North West of Iran. Re-examination of the specimen (IRAN 16881F) revealed a misidentification of the smut species. The specimen showed following morphological features: Sori on the basal part of stem forming fusiform swellings, initially grayish-silver color and covered by the epidermis which ruptures longitudinally revealing the black, granular-dusty mass of spore balls. Spore balls sub-globose, elongated or rounded irregular, 17.5−47.5 × 14−34 µm (measured in Lactic acid in glycerol), dark brown, composed of 1−7 spores surrounded by an incomplete layer or only a few sterile cells. Spores sub-globose to ellipsoidal, often flattened on contact sides, 13.5−20 × 10−15 µm, dark reddish-brown, smooth. Sterile cells sub-globose, elongate to pyriform and irregularly flattened, 6−12.5 µm long, 3.5−6 µm wide, light yellowish-brown, smooth (Fig. 1). These morphological features fit the description of Urocystis ceratocephali Zambett. ex Vánky (Vánky & Abbasi 2013) and differ from the morphological characteristics of U. eranthidis (Pass.) Ainsw and Sampson mentioned by Vánky (2012). Comparison with an authentic specimen of U. eranthidis (HUV296) collected from Germany, confirmed differences between IRAN 16881F and U. eranthiidis. Urocystis ceratocephali differs from U. eranthidis in having a different host, spore balls composed of up to 7 spores, producing sori only on stem and granular dusty mass of spores (Table 1). There is only one previous record of U. ceratocephali from Iran on Ceratocephala falcata, collected from Esfahan Prov., on the way between Shahreza and Semirom cities (Vánky & Abbasi 2013).