SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f8b0bda1c328035981bb16994c8250e65951c9cdad87be4ceb7f4147565bc7f' 
  AND token = 'lsYyFrEBj3qcKoXzvXqODlOFM1cCzgCFrNLoIZl6RuM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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