When people talk about the Five Races, they mean, collectively:
Suitov Iceheart appears to refer to these by Latinesque nomenclature, with faleigh being H. robustum, ferais H. gracile, voks H. agile, srolli H. bassum and rocca H. caerulum. Whether this is canonesque taxonomy or just him being OOCly irritating is not yet known.
Mutt takes the view that Shade's sapients are similar, down to a cellular level, to other humanoids, but are completely genetically incompatible. In other words: your alien can poison one, can stab one in the heart, can't get one pregnant. (There may be other small anatomical differences, such as teeth: this isn't known yet.)
Incidence of left-handedness: roughly 2 in 7.