Key to species of terrestrial isopods from Isla Grande

1. Eyes present....................................................................................................................................... 2

– Eyes absent ............................... Stenoniscus nestori López-Orozco, Taiti & Campos-Filho sp. nov.

2. Animal with conglobation ability ...................................................................................................... 3

– Animal without conglobation ability. ................................................................................................ 6

3. Pereon dorsally smooth; pereonite 5 epimera with ventral phylacomera.......................................... 4

– Pereon dorsally tuberculate; pereonite 5 epimera without phylacomera ............................................ ......................................................................................... Ctenorillo tuberosus (Budde-Lund, 1904)

4. Phylacomera 5 paddle-shaped, extended anteriorly .......................................................................... 5

– Phylacomera 5 sickle-shaped.................................................. Tylos marcuzzii Giordani Soika, 1954

5. Inner lobe of schisma extending beyond posterior margin of outer lobe ............................................ .................................................. Tylos negroi López-Orozco, Carpio-Díaz & Campos-Filho sp. nov.

– Inner lobe of schisma not extending beyond posterior margin of outer lobe ...................................... .......................................................................................................... Tylos niveus Budde-Lund, 1885

6. Flagellum of the antennae with 4 or more articles ............................................................................ 7

– Flagellum of the antennae with 2–3 articles.................................................................................... 10

7. Flagellum of the antennae with 4 articles.......................................................................................... 8

– Flagellum of the antennae with more than 10 articles......... Ligia baudiniana Milne-Edwards, 1840

8. Dorsal surface almost smooth or with small tubercles ...................................................................... 9

– Dorsal surface of pereon with 4 prominent longitudinal ribs .............................................................. ....................................................................... Armadilloniscus caraibicus Paoletti & Stinner, 1989

9. Dorsal surface almost smooth.................................................. Armadilloniscus ninae Schultz, 1984

– Dorsal surface with small tubercles..................................................................................................... .................................................. Armadilloniscus luisi Carpio-Díaz, Taiti & Campos-Filho sp. nov.

10. Flagellum of the antennae with 3 articles.........................................................................................11

– Flagellum of the antennae with 2 articles........................................................................................ 14

11. Genital papilla with truncate apex ................................................................................................... 12

– Genital papilla with bifurcated apex....... Halophiloscia trichoniscoides (Vandel, 1973) comb. nov.

12. Male pleopod 1 endopod without lobe on outer margin of apical part............................................ 13

– Male pleopod 1 endopod with a lobe on outer margin of apical part .................................................. ................................................................................ Littorophiloscia tropicalis Taiti & Ferrara, 1986

13. Male pleopod 1 endopod with apex divided into three points............................................................. ........................................................................... Littorophiloscia amphindica Taiti & Ferrara, 1986

– Male pleopod 1 endopod with a long spine and 2 small distinct denticles on the inner margin of the apical part.......................................................... Littorophiloscia denticulata (Ferrara & Taiti, 1982)

14. Pleopod exopods with lungs ............................................................................................................ 15

– Pleopod exopods without lungs....................................................................................................... 16

15. Pleopodal lungs present in first two pairs of pleopods ...... Porcellionides pruinosus (Brandt, 1833)

– Pleopodal lungs present in all five pairs of pleopods .......................................................................... ................................................................................ Agnara madagascariensis (Budde-Lund, 1885)

16. Colorless body; eyes composed of two unequal ommatidia................................................................ ........................................................................ Trichorhina heterophthalma Lemos de Castro, 1964

– Pigmented body; eyes with 10 ommatidia........................................................................................... ................................ Trichorhina bermudezae Carpio-Díaz, López-Orozco & Campos-Filho, 2018