SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afef0389f61d99ac7df67c9f07a974ffd471c12ce2ff92f769ffef40b35877a3' 
  AND token = 'q29+UXFvQjoyehj3rkcqnOyaPsrv4fc03Xwnj2hj17E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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