SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3f453a26e50ed322328a22b086bc1a912f51444956f5fe18fb88631eaca66da' 
  AND token = 'yl0IVDk6SaCmI93xGEJMtRp6iZVCIYUumUSOk2pOnQw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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