SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf5a2cc277005141ec10a9e43bc76b3bcd29a953eb32c6a4e67ff5db50b404e1' 
  AND token = 'xHa4wSIGLfNurWJ63qD+XtLwQYwFGT79x7dqtk6DKQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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