SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46022165320cc457becbb731a35beb0856ec1803f2ddd7c178207af884fc2303' 
  AND token = 'Hd/+9NC6fwFbACQXXqLJEwH0055TiDqz1MIvPSXEfhI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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