i think these are correct but would appreciate help with the parsing........
7a. Run with servicemen in confines of burnt-out plant (11) - BLADDERWORT (Plant) I can see 'Servicemen' = OR + W(ith) + R(un) but that leaves 'Bladdet' so I've obviously gone wrong somewhere.
35a. Exceed old record at length in Russia (8) - OVERSTEP (Exceed) Other than O(ld) and EP (record) I'm at a loss.
2d. Pigment found in land, not lake (5) - UMBER (Pigment) I thought it was suggesting that if you add an L(ake) you get a 'Land' - but you don't.
4d. Fermented drink and ancient Indo-European talked of (4) - MEAD (Fermented drink) I think it'a a homophone but of what?
8d. Artist covering up mark in host's rich clothing (5) - ARRAY (Clothing) Other than RA (Artist) I'm lost.
55a. Bird wheeling about lake with fine Scottish stags (4,7) - REED WARBLER (Bird) I think it's 'Stags' = DEER reversed (wheeling) and L(ake) but I can't see the rest.