Solar
~Kayasthas and the cult of Sun worship ~ In Bhinmal Stone inscription of Udaysimhadeva VS 1306, we find reference to two sons of Thakkura Udaysimha of Mathur subcaste.The two brothers donated to treasure of Jagatswamin, Surya Divinity of Bhinmal.
The same diety has been referred to as Kuldevta of Narapati ,kayastha minister of Hammira of Ranthambore in inscriptions of Hammira era.
Mathurs like other major subcastes of kayasthas trace their descent from Lord Chitragupta. Vishnudharmottara purana describes Lord Chitragupta dressed in Udichyavesa on right side of Yama.This iconography resembles companion of Surya, Pingala.Udichyavesa is associated with form of Surya worship introduced by Iranian Magis.
The imagery of Udichyavesa was inspired by Iranian diety Mithra.Interestingly in Skanda purana, Citra is said to be son of a pious Kayastha called Mitra .In that very texts he is said to be one of 14 Yamas too.
The SambaPurana mentions Chitragupta as Jandakara once attended to Sun God.HC Hazra points out that the name Jandakar is of Avestan origin.
Iranian Magis are said to be ancestors of Sakadvipi Brahmins.Suryadhwaja kayasthas ,an important subcaste of kayasthas were definitely Sakadvipi Brahmins.This is corroborated by an inscription from 8th century.
The Hund insciption of 8th Century AD was composed by Suryadwija kayastha Sri Bhogika.Scholarly opinion is that he was a Sakadvipi Brahmin. This indicates that Suryadhwaja kayasthas emerged out of Sakadvipi Brahmins.
Theres certainly a lot of overlap between iconography of Lord Surya and Lord Chitragupta. Lord Chitragupta if we go by the legend of Chitraaditya in a way was definitely an intellectual progeny of Lord Surya .
bauddha
Vairocanavajra was a prominent medieval era Buddhist master from Dakshin Koshala.His disciple Lama Zhang went on to establish tshalpa Kagya sect .Lama Zhang pays homage to Vairocanavajra in one of his works and describes Vairocanavajras Kayastha teacher Surapala. Surapala , the kayastha also wrote very important 10th century treatise Vrikshayurveda which is said to be one of first text applying principles of ayurveda to plants ,touching on topics like pest control.Surapala is said to be an expert in Siddha Yogas. Another teacher mentioned in lineage of Vairocanavajra preceding Surapala is called Kayasthapada. Little is known about Kayasthapada.