Munnogonium George & Stromberg 1968

Key to species of Munnogonium

1. Frontal margin with projection; pereionite 1–4 lateral margins coxae not visible in dorsal view............................ 2

- Frontal margin without projection; pereionite 1–4 lateral margins coxae visible in dorsal view........................ 3

2. Pleotelson lateral margin convex; antennula article 1 length shorter than article 2; antennula articles 4–6 of subequal length, all shorter than 3; antenna article 5 distinctly longer than article 4.... Munnogonium diplonychia Doti & Roccatagliata, 2013

- Pleotelson lateral margin with proximal neck before convex margin; antennula article 1 length subequal to article 2, or longer than article 2; antennula articles 4 and 6 shorter than articles 3 and 5; antenna article 5 only slightly longer than article 4........................................................... Munnogonium quequensis Doti & Roccatagliata, 2013

3. Pleotelson posterior margin evenly curving into lateral margin................................................. 4

- Pleotelson posterior margin set apart from lateral margins by concavity at level of uropods....................................................................................... Munnogonium falklandicum (Nordenstam, 1933)

4. Pereiopod I merus posterior margin with fine setae only; uropods on lateral margin of pleotelson...................... 5

- Pereiopod I merus posterior margin with one robust seta on distally; uropods dorsal and directly adjacent to lateral margin of pleotelson........................................................................................... 7

5. Antennula article 1 length subequal to article 2, or longer than article 2; pereiopod I coxa in terminal males fully fused to pereionite 1; pereiopod II propodus ventral margin with simple setae only... Munnogonium tillerae (Menzies & Barnard, 1959)

- Antennula article 1 length shorter than article 2; pereiopod I coxa distinctly articulated on pereionite 1; pereiopod II propodus ventral margin with short robust setae..................................................................... 6

6. Pereiopods II basis posterior margin in males without projections; pereiopod II carpus ventral margin with row of elongate robust setae; pereiopod II dactylus dorsal claw thin, longer than dactylus length; male pleopod I lateral lobes distal sublobe with robust seta on apex................................................. Munnogonium globifrons (Menzies, 1962)

- Pereiopods II basis posterior margin in males with distal lobe; pereiopod II carpus ventral margin with short robust setae; pereiopod II dactylus dorsal claw robust, shorter than dactylus length; male pleopod I lateral lobes distal sublobe with tuft of simple setae......................................................... Munnogonium erratum (Schultz, 1964)

7. Frontal margin broadly rounded; body widest in male at pereionite 4; pereiopod I propodus opposing margin with robust seta; uropod endopod distal margin rounded.................................... Munnogonium longicaudatum sp. nov.

- Frontal margin concave medially; body widest in male at pereionite 3; pereiopod I propodus opposing margin with simple setae; uropod endopod distal margin with rounded point medially, curving laterally....................................................................................... Munnogonium waldronense George & Strömberg, 1968