Question

which parties are known as leftist parties

Answer 1

Pro-Left Front Communist Parties

Left United Front

Pro-Chinese Naxal/Maoist Communist Parties

Pro-Congress/UPA Communist Parties

Pro-BJP/NDA Communist Parties

Other Communist Parties

Answer 2

Leftist Parties are those demands for Secularism, Abolish of Castes, Fighting against Social Divisions. They can also be said as Non-religious based party.

These are some left paries
And Congress is the head of United Progressive Alliance ( UPA )

i)Socialist Unity Centre of India (Communist)
ii)Communist Marxist Party
iii)Revolutionary Socialist Party of Kerala (Bolshevik)
iv)Marxist Co-ordination Committee
v)Provisional Central Committee, Communist Party of India (Marxist–Leninist)
vi)Marxist Periarist Communist Party
vii)Revolutionary Marxist Party

:) Hope this Helps!!!