I send you a pictorial material about Zygomycetes (see web side) from my colleagues Dr. Alena Kubatova and dr. Marie Vanova from Department of Botany, Faculty of Science, Charles University in Prague
Gulnaz, there are many books and several monographs on identification of fungi on morphological basis apart from recent molecular methods. The following books will help you on the basics in speciation of fungi:
Illustrated Genera of Imperfect Fungi, H.L. Barnett, Burgess Publishing Company, 426 S. Sixth Street, Minneapolis 15, Minn.
A Manual of SOIL FUNGI, Joseph C. Gilman, The Iowa state University Press, Ames, IOWA, USA
In recent times, many new fungi are reported. Now, molecular methods have come to solve many riddles in mycology. Start from basics and gradually you will be well versed with taxonomy and speciation of fungi.