SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efeec6405e45d6b0967b0c67f68dc4de7d8aa3ab0a3c7847b2298b8fcfc03b06' 
  AND token = '7wxWJLe6qYQrovD2AKFMUU3BdRqr030OgkfC7FckiY8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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