Metabetaeus, Borradaile, 1899:, 1899

Yamashita, Ryunosuke, Komai, Tomoyuki & Kon, Koetsu, 2023, Metabetaeus lapillicola, a new species of alpheid shrimp (Decapoda: Caridea) from Japan, inhabiting unusual pebble beaches, Zootaxa 5258 (3), pp. 317-330 : 328

Key to species of Metabetaeus

1. Carapace with pterygostomial spine; chelipeds greatly unequal and dissimilar with major one noticeably elongate; uropodal endopod unarmed or at most with rudimentary tooth on distolateral margin........................ M. lapillicola n. sp.

- Carapace without pterygostomial spine; chelipeds subequal and similar; uropodal endopod with conspicuous tooth on distolateral margin............................................................................................. 2

2. Corneas developed; pereopods 2 and 3 propodi each with 1 or 2 minute spiniform seta(e) or unarmed on flexor margin............................................................................................ M. mcphersonae

- Corneas reduced; pereopods 2 and 3 propodi each with numerous spiniform setae on flexor margin.................... 3

3. Cheliped fingers shorter than palm, not curved...................................................... M. minutus

- Cheliped fingers longer than palm, more or less curved............................................... M. lohena