SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '954fc402558e3468829951516b6dfeb8eb9eb08925dfa5cc768c2686f113e7ce' 
  AND token = 'R8CWQBxuxXqfRR+omIkQlRApXEqew//nEJTnzqKWnFA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}