The Jhags
Fiddler's POV: '...an extraordinarily tall man, lean...His skin was somewhere between grey and green... His long, grey hair showed remnants of black dye, making his mane appear spotted ... ragged tips of tusks bulging the line of his thin lower lip. A Jhag. Didn't know they travelled this far east.(DG, UK MMPB, p.301-2)
Jhags are the product of a Jaghut mating with a ...non-Jaghut. It is uncertain what pairings will produce offspring, though Aramala in House of Chains seems to suggest that Toblakai can successfully mate with Jaghut. That and other possibiites are listed below in order of likelihood (imo):
Jaghut x Toblakai
Jaghut x Barghast (Toblakai/Imass)
Jaghut x Trell (descendants of Toblakai)
Jaghut x Imass
Jaghut x Eres
Jaghut x Human
Jaghut x Tiste Races (doubtful)
Jaghut x Forkrul Assail (very doubtful)
whether or not Jhags are sterile, as with mules, is another unanswered question. The only Jhag we have directly see is Icarium, though Aramala speaks of more when Karsa frees her (ref's to come)
Icarium seems to have a kind of darkvision, neither he or Mappo having 'much need for artificial light, the darkness...offering no obstacle.' (DG, UK MMPB, p.172) Whether or not this is a racial trait is a separate question, though it seems likely to be.
The Chanters
'He (Tiny Chanter) turned about and studied his eleven brothers and two sisters, not one short or even of average height, not one not bound in massive muscle - women included - and he smiled...thick- boned skulls. Silver-sheathed tusks gleamed on a few of the men who betrayed more than the normal hints of Jhag blood.' (Lees, p. 114)