Hyphomycetous genus Gibellula Cavara accommodates species that are highly specialized and apparently are obligate parasites of spiders with worldwide distribution (Samson, R. A. & Evans, H. C., 1992; Mycologia, 84: 300-314). Their taxonomy has been discussed and identification key to eight accepted species and a variety is presented by (Samson & Evans, l. c.). Conidiogenesis is phialidic and their teleomorph belong to Torrubiella Boud. (Samson & Evans, l. c.). In a survey to Shastkola forest in the north of Iran, Golestan Province (Gorgan), a specimen on a dead spider on underside of Persian Ironwood (Parrotia persica (DC) CA. Mey) was collected and identified as G. leiopus (Vuill.) Mains. Macroscopic and Microscopic features of the fungus are given bellow.
Dense white to yellowish mycelium and synnemata covered the whole body of the spider. Synnemata cylindrical or slightly clavate, white, becoming pale orange with age, 1-2 ´ 0.3-0.6 mm, composed of parallel densely compact hyphae. Hyphae septate, hyaline to yellowish white to grayish yellow, mostly smooth, 1.5-4.5 mm wide. Conidiophores dense arising at the ends of hyphae of the synnemata or laterally from the arched hyphae of the synnemata, crowded, particularly on the upper portion, 25-45 mm long, mostly smooth. Vesicles mostly ellipsoidal to globose, smooth, hyaline, 6-11 mm diam, bearing a number of metulae on the upper part. Metulae ellipsoidal, broadly cylindrical to obovoidal, hyaline, smooth, 7.5-9´3-4.5 mm, bearing a number of phialides at the apices. Phialides subcylindrical, tapering towards the apex, smooth, hyaline, 7.5-9´1.8-2.2 mm. Conidia mostly ovoid, ellipsoidal, cylindrical to fusiform, sometimes obclavate, hyaline, smooth, single or in chains, 3.5-4.5´1.5-2 mm. These dimensions were very close to those of the above paper. This is the first report of a Gibellula species from Iran. Another Gibellula species was collected from a dead spider on the underside of a leaf in Jannat rudbar, Mazandaran Province on 14 September 2004 that could not be identified to species as it was mostly broken and damaged, but with its longer verrucose conidiophores and radiate conidial heads was clearly different from the above species. Slide and specimen of G. leiopus (IRAN 12670F) and Gibellula sp. (IRAN 12671F) are preserved in the Fungus Collection of the Ministry of Jihad-e Agriculture. |