Synalpheus quadriarticulatus Banner and Banner, 1975
Synalpheus quadriarticulatus is an Indo-West Pacific snapping shrimp first described from Australia. For more details, see ABRS (2009): http://www.environment.gov.au/biodiversity/abrs/online-resources/fauna/a....
The species name Synalpheus quadriarticulatus refers to the distinctive feature of four carpal articles on the second leg. Type locality: Torres Strait, Queensland, Australia (Banner and Banner 1975), types stored at the Australian Museum, Sydney, New South Wales, Australia (AM). Type: AM P19161.
The type series were collected from a cryptic sponge living in coral rubble, 3-18 m depth (Banner and Banner 1975, Chace 1988).
Banner and Banner (1975) noted that the type female carried only very large eggs, and noted a skewed sex ratio in the type series (one female collected in the same sponge as one mature male and 6 immature individuals).
Maximum body size is 11 ml TL (female holotype, Banner and Banner 1975), 4 mm CL (Chace 1988). Like a few species in the West Atlantic (S. filidigitus, S. barahoenensis, the S. rathbunae species complex), S. quadriarticulatus has four articles on the carpus of the second leg; it can be distinguished from these species by the lack of the strong tuft of setae on the minor chela (for more details, see Banner and Banner 1975). Morphologically similar also to S. pescadorensis, but differs by having four articles on the carpus, by shorter basal antennular articles, and by several other characters (Banner and Banner 1975). S. redactocarpus and S. dorae (from the Pacific) also have four fingers on the carpus of the second leg; S. quadriarticulatus can be separated from the latter by the shape of the telson, which in S. dorae has two pairs of large dorsal spines and two pairs of subequal posterior spines (Bruce 1988).
Indo-West Pacific: Queensland, Australia (Banner and Banner 1985); Philippines (Chace 1988).