According to Kovarik (2004) in its key for species in the genus Heterometrus, the distinctive character for H. spinifier is that much of the dorsal surface of fingers is smooth and punctate while this is not the case in H. longimanus, a species with male chela narrow and long, its length to width ratio greater than 3.3. Please refer to the abovementioned article in Euscorpius, nr. 15, pp. 1-60 (2004) for more details.

How about this specimen? H spinifer or longimanus?

Looks like H longimanus to me. 

No difference clinically. Manage symptomatically.