Sena members, wearing saffron pheta (headgear) came to the assembly in a group and occupied the opposition benches.
Earlier on Monday, before proceedings began at 11 am, the governor administered the oath as Pro tem Speaker to senior legislator Jeeva Pandu Gavit, at Raj Bhavan.
Gavit then administered the oath to newly elected members of the House. The process will continue on Tuesday. On November 12, the last day of the session, election for the Speaker will be held.
Shiv Sena sources said that the party was likely to field its nominee for the post.
While senior Sena leader Neelam Gorhe said that her party was at present not involved in any talks with the Bharatiya Janata Party.
Sena chief Uddhav Thackeray had on Sunday announced that the party will sit in opposition if the BJP accepted the Nationalist Congress Party's support to win the trust vote.
Uddhav has given the BJP two days to respond, before taking a final decision.
Senior Sena leader Diwakar Raote said that the Sena MLAs will present a green skull cap to revenue minister Eknath Khadse for "espousing" the cause of Urdu language in Marathi medium schools.
Monday was also the first day as MLA for former chief minister Prithviraj Chavan and education minister Vinod Tawde.
Interestingly, while some members invoked God before taking oath, there was a member who said "Jai Vidarbha" while there was another who said "Namo" while taking oath.
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