All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
We found the biography of Yahya ibn Muzayn in Al-Qaadhi ‘Iyaadh's book Tarteeb Al-Madaarik. Below is a summary of that biography:
His name is Yahya ibn Muzayn, originally from Tulaytilah (Toledo). He moved to Qurtubah (Córdoba) during the revolt in Tulaytilah. He met Mutarrif ibn ‘Abdillaah and studied Al-Muwatta' at his hands. He also studied it at the hands of Habeeb, the scribe of Maalik. He traveled to Iraq and learned from Al-Qa‘nabi and Ibn Yoonus. In Egypt, he learned from Asbagh ibn Al-Faraj. He memorized Maalik's book Al-Muwatta' and was remarkably versed in the Maaliki Fiqh and had a share of studying the science of the Arabic language. Ibn Lubaabah said, "He (Yahya ibn Muzayn) was the most knowledgeable scholar of the Fiqh of Maalik and his companions I have ever seen." Ibn Haarith said, "His refined status among scholars is no secret. He did not relate ahaadeeth often and was endowed with good memory and intelligence."
As for Yahya ibn Maryam, we could not find his biography in any of the books available to us. Rather, he was not mentioned in many of the Maaliki books or those citing the biographies of the Maaliki scholars; he may be mentioned with a nickname other than "Ibn Maryam".
Allaah knows best.