there are different ideas of dark psy, evolving with the time (very quickly).
nowdays dark psy artists are names such as Furious, Cosmo, Terranoise, Orestis, Kindzadza and even Psykovsky to some extent (although woldnt call his music psytrance really).
then there's forest - organic psy where the main artists are Atriohm, Ajja, Electrypnose (very eclectic)..would raccomend Parvati, Peak, Blue Hours Sound, Sanaton and Psynon records.
Absolutely mindblowing music in my opinion, especially the forest-organic bit. Ajja is really a top producer, would raccomend his chill out production too, together with the peaking goodness collective, basically the top 4 artists of peak recs producing a mostly downtempo album together, with live instruments.
I also love slackbaba production but it's off topic as it's more psydub/psybreaks stuff.
there are some real gems in psytrance..pity for the "trance" bit that is misleading as it has nothing to do with knobs such as tiesto, eskimo, infected mushrooms and so on..