gillless

From gill +‎ -less.

• IPA^(key): /ɡɪlˈlɛs/

gillless (not comparable)

1. Lacking gills.

   Some salamanders are both gillless and lungless as adults, relying solely on cutaneous respiration to breathe.

   • 1982, L. Patrick Coyle., The World Encyclopedia of Food:

     ...which closely resembles the golden chanterelle, except that it is white and slightly larger; the gillless chanterelle...

   • 1992, J.V. Ward., Aquatic Insect Ecology:

     However, in Cloeon evidence from experiments with gilled and gillless nymphs suggests that the primary, perhaps sole, function of gill movement is to reduce...

   • 2002, M. Prakash, C. K. Arora., Encyclopædia of Animal Physiology:

     ...borne by four branchial arches, and the fifth arch is gillless...

Three letters are rarely grouped together in English (only in compound words such as headmistressship and skulllike), and when so, they are typically hyphenated to avoid the triplet (gill-less).