  Penium granulatum | 
  Penium interruptum | 
  Penium jenneri | 
  Penium jenneri | 
  Penium libellula | 
  Penium libellula | 
  Penium libellula var intermedium | 
  Penium libellula var. interruptum | 
  Penium margaritaceum | 
  Penium margaritaceum | 
  Penium minutissimum | 
  Penium minutum | 
  Penium mooreanum | 
  Penium mooreanum | 
  Penium naegelii | 
  Penium navicula | 
  Penium navicula | 
  Penium navicula var. crassum | 
  Penium navicula var. inflatum | 
  Penium oblongum | 
  Penium phymatosporum | 
  Penium polymorphum | 
  Penium refescens | 
  Penium spinospermum | 
  Penium suboctangulare | 
  Penium subtile | 
  Penium truncatum | 
  Penstemon barbartus | 
  Penstemon barbatus | 
  Penstemon barbatus | 
  Penstemon barbatus | 
  Penstemon barbatus | 
  Penstemon bridgesii | 
  Penstemon bridgesii | 
  Penstemon bridgesii | 
  Penstemon bridgesii | 
  Penstemon campanulatus | 
  Penstemon campanulatus | 
  Penstemon confertus | 
  Penstemon corfertus | 
  Penstemon digitalis | 
  Penstemon digitalis | 
  Penstemon digitalis | 
  Penstemon fruticosus | 
  Penstemon gracilis | 
  Penstemon gracilis | 
  Penstemon gracilis | 
  Penstemon gracilis | 
  Penstemon gracilis | 
  Penstemon gracilus | 
  Penstemon hirsutus | 
  Penstemon hirsutus | 
  Penstemon hirsutus (pubescens) | 
  Penstemon hirsutus (pubescens) | 
  Penstemon hirsutus (pubescens) | 
  Penstemon palmeri | 
  Penstemon pinifolius | 
  Penstemon pinifolius | 
  Penstemon pinifolius | 
  Penstemon pinifolius |