SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b11cfbbae268974274f135e96960f63e9db7fc16c2558486e823b0c7ab061f1' 
  AND token = 'XtC7reBPiSPdWRLFvNkDsUdXNGr3WpuwAEbQdTmcMEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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