Let us therefore see what the term "speaking in tongues" might involve, as analyzed by the Apostle Paul in Ephesians:

"instead, be filled with the Spirit, saying (λαλούντες) to yourselves Psalms and hymns and spiritual odes, singing and chanting in your heart to the Lord, always thanking Him, for everything......"  [Ephesians 5:18-20]

When someone is "in the Spirit", he "speaks within himself" - in other words, internally - in all the ways that the verse mentions, which are the various kinds (species) of "glossolalia" - the "speaking in tongues".

The aforementioned are an evolved form of "I chant in the Spirit" of 1 Corinthians 14:15, and different to "I chant also with the mind".

Let me pray in the Spirit, and let me also pray with the mind.

Let me chant in the Spirit and let me also chant with the mind...

It is also a reflection of 1 Corinthians 14:18, where the Apostle Paul says: More than all of you, I speak (λαλών) in many tongues. (In other words, "I speak in more tongues than all of you").

Thus, when referring to the species of tongues, we do not imply the languages that are spoken by human voices, but the manifestations of the Holy Spirit, which take place mutely inside the heart, but which can also be expressed through the human voice.