SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f7114f92d710fd46d926ef7647cfbe53abb3aa8fa3c45d403f847b263e31881' 
  AND token = 'TDdqpY5Cuyq/9IYWsw0rXyAyH5UwDUvpPsU6HWfiAqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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