SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6faf1a71d9902e63d6fd34f8b31902694844a7f23a3c399eb607ff8ce3184628' 
  AND token = 'QlvLlqRkMRAjDpfaCuYMVQjKikXQw7bwJEpCuhsFiPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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