Hi AMS,
The classic example of an extreme warm water killifish species are the desert pupfish of the genus Cyprinodon although they are not as colourful as say the African varieties such as Aphyosemion and Nothobranchius, nevertheless the are still stunning in their own right. Certain varieties of killifish will do quite well in the higher temperature bracket you mention but it speeds up their metaobism and in turn this shortens their lifespan. Also temperature plays a big part in their breeding and egg reproduction as regards to sex ratios of the resulting fry.
I hope this was of some help.
Regards
BigC
