SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d511827ee5a7cfad894dc22fbccaade4ca2aacf3bd3389381abee3298a6dd67' 
  AND token = 'x0updRhyNHUaHc2FqFGXwqmiDatg497T2IxPkDQuAYg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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