Tirons of the world: a review of ‘ tironid’ amphipods, description of new genera and species, and establishment of a new subfamily Tironinae Stebbing, 1906 stat. nov. (Crustacea, Synopiidae) Author Just, Jean text Zootaxa 2022 2022-05-23 5139 1 1 89 http://zoobank.org/145cb6f5-2ea8-40b0-9cca-3e942aa4a5b9 journal article 95147 10.11646/zootaxa.5139.1.1 8ab25605-ec09-4d57-9dbd-7da2b032e5e8 1175-5326 6572023 145CB6F5-2EA8-40B0-9CCA-3E942AA4A5B9 Key to the genera in Tironinae (See also Fig. 1 ) 1. Pereopods 3–7 dactylus short, with curved robust seta countering short curved unguis, (pre-stubby, Fig. 1 b )............. 2 - Pereopods 3–7(6) dactylus and unguis strongly modified and complex, with curved robust seta countering modified unguis, (stubby, Figs1a , 38x ).................................................................................. 3 2. Head in lateral view evenly curved to downward pointed acute rostrum, eyes and accessory eyes present, coxal plate 3 rectangular, uropod 1 outer ramus of single article, reaching well beyond uropod 2..................... Tiron Lilljeborg, 1865 - Head in lateral view with anterior front rounded, dorsal and anterior margins straight, at right angle; rostrum apex sharply pointed at 90° angle; interantennal lateral head margin with about 100° blunt projection; coxal plate 3 widening distally to broadly rounded apex and slight posterodistal concavity; uropod 1 barely reaching end of uropod 2, uropod 3 outer ramus of single article........................................................................... Tironella gen. nov. 3. Mandible palp present; uropod 3 outer ramus with small article 2, uropod peduncles, and telson with rows of elongate glands....................................................................................................4 - Mandible palp absent; uropod 3 outer ramus of single article, urosome without glands............................... 5 4. Mandible palp article 2 straight; coxal plates 3–4 pelagont (see key to family, notes and Fig.1 ).. P s eudotiron Chevreux, 1895 - Mandible palp article 2 curved, coxal plates 3–4 similar, not pelagont......................... Glandulotiron gen. nov. 5. Gnathopod 1 basis straight ( Fig. 43a ), maxilla 1 outer plate with broad oblique row of spine-setae ( Fig. 43b )......................................................................................... Metatiron Rabindranath, 1972 - Gnathopod 1 basis strongly curved ( Fig. 43c ), maxilla 1 outer plate with narrowly amassed group of elongate, apically curved spine-setae ( Fig. 43d ).................................................................... Minitiron gen. nov.