Complex sentence: The spotfin shiner has a black blotch of pigment on the membrane between its last three rays of the dorsal fin; this spot may be obscure or faint in small spotfin shiners.
Split into simpler sentences: The spotfin shiner has a black blotch of pigment on the membrane between its last three rays of the dorsal fin. This spot may be obscure or faint in small spotfin shiners.