SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd691eb83b01a304bfb09d0f9159e2f2ef99ad983c6dd091356f4bf32916dd7a5' 
  AND token = 'FA+8cq7xXr0t6g9GAnfK6EuakckC6r4eDPo3HnGmcBw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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