SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33bd019eba7cd4a82f624a2a95980cc949675ce54efc072031e19110c277424a' 
  AND token = 'PmwjO+8J3rKL6Bnng9N2oVtj4Xs1XVW3Soo3voJzT1w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}