Fig. 44 of the Sermonibus Animalis series.  It's a good thing the Rough-Throated Leaf Tailed Gecko is bred in captivity. This one in particular has his own fancy bathtub, where he's known to play with his aquatic toys - ever the herpetological sea captain!
 
Original illustration w/ ink & brush tip marker on textured, parchment toned paper.  
 
8.5" x 11"