SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d241ac144db8e53ed0a988cfdf5ca15e106199996dcbecb7bce3797639b3e5b' 
  AND token = 'Ieu++MVWhA60hIRXeQ6GjVvhqCli4Qq4Z5i30F6RAXY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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