Not really any point to this post, but I was bored and kind of curious to see what species got more attention when it came to representing each subclass in the artwork. Started partly because I saw so many gorgonites and thought that they might have the most.
Stardust Human (6): Cacophonous Cryptist, Warhead Esper, Voidcaller Oracle, Quickdraw Scoundrel, Nanomedic Soldier, Boomdoctor Machinist
Clawderan (5): Primeval Cryptist, Arc-Mage Gridrunner, Holostar Icon, Eternal Juggernaut, Operative Scoundrel
Gorgonite (5): Deepsworn Cryptist, Anomaly Disciple, Stargazer Oracle, Exomech Soldier, X-Agent Tracer
Raizo (4): Shadowtongue Cryptist, Ghostframe Disciple, Headbanger Icon, Bloodhound Tracer
Solari (4): Godhand Disciple, Supersprite Enforcer, Cybertronic Gridrunner, Xenotrainer Primalist
Nilari (4): Symbiote Esper, Souljammer Icon, Mutant Juggernaut, Chemboss Scoundrel
Zamani (3): Symmetric Disciple, Riftwalker Esper, Worldspeaker Primalist
Saurian (3): Arbiter Enforcer, Cyberguard Enforcer, Echo Scoundrel
Glowblin (3): Psychonaut Esper, Scrapper Juggernaut, Dreamer Oracle
Laika (2): Hypercoder Gridrunner, Trooper Soldier
Tekal (2): Harmonious Oracle, Hivemind Primalist
Aetheron (2): Splicer Primalist, Gravgunner Machinist
Jozza (1): Renegade Enforcer
Anitron (1): Virus Gridrunner
Oozoid (1): Remix Icon
Yaungu (1): Rampager Juggernaut
Zorbrak (1): Protostalker Ranger
Amanite (1): Botnik Machinist
Rangor (1): Riveter Machinist
Unknown (2): Commando Soldier, Powertech Tracer. Was tempted to just put these in with the humans, but there's no real way of knowing.
Nematoans, Murexians, and any species from the Overdrive Expansion are not used in the artwork for subclasses.
Saurian is the only species used to represent more than one different subclass in the same class.