Siriellinae Norman, 1892

Talbot, Suzette, 2009, A survey of Mysida from the Lizard Island area, Great Barrier Reef, Australia, Subfamily Siriellinae (Crustacea, Mysida, Mysidae), Zootaxa 2114, pp. 1-49 : 5

Siriellinae Norman, 1892

Diagnosis. Proximal part of antennal scale smooth and ending in a toothed notch; endopod of thoracic limbs with brush of stiff serrated setae at base of dactylus; female marsupium made up of 3 pairs of oostegites; uropodal exopod divided by a diaresis into two articles, outer border of the proximal article armed with simple robust setae, (except that of Siriella dubia , which has both robust and plumose setae); uropodal endopod undivided; telson without cleft and usually linguiform.

Remarks. Murano (1986) proposed that the members of the subfamily be grouped into two tribes, the Siriellini , to contain all but one of the known siriellids and the Metasiriellini , to accommodate a new species, Metasiriella kitaroi , described by him from the vicinity of the Philippine Island of Panay. Its unique features and highly unusual combination of characters led him to separate it from the other siriellids.

The Siriellini is made up of two genera, Siriella and Hemisiriella and is characterised by the males having pleopods with coiled or straight pseudobranchiae at the base of the endopods and by the 2nd–5th male pleopods being biramous and natatory, with some species having enlarged, modified setae on the 3rd and 4th male pleopods, or on the 4th only. Both genera are represented in the Lizard Island material. In Siriella , the endopods of the thoracic limbs are all of approximately the same length, while in Hemisiriella , the 3rd thoracic endopods are stout and elongated to about twice the length of the adjacent endopods. Metasiriella kitaroi contrasts with both of these genera in the structure of the male pleopods, the 1st, 2nd, 3rd and 5th resembling those of female siriellids, in that they are small, uniramous, consist of one article only and lack pseudobranchiae. The 4th pleopods differ in being biramous and multiarticulate, with endopods that bear a unique rectangular pseudobranchial lobe at the base and that terminate in a pair of enlarged and modified setae.