Nippenose Valley cave (A–C, F) and epigean Antes Creek (D–E, G) sculpins. While there is a diversity of expression of troglomorphic characters, cave fish tend to be more depigmented (A–C vs D–E), have smaller eyes (F vs G), more abundant and larger mandibular pores (F vs G, arrows point to pore III), larger heads (B vs D), and longer pectoral fins (B vs D). Scale bar: 2 cm (A–D, F–G modified from Espinasa and Jeffery (2003)).

  Part of: Espinasa L, Smith DM, Lindquist JM (2021) The Pennsylvania grotto sculpin: population genetics. Subterranean Biology 38: 47-63.