Synalpheus belizensis Anker and Tóth

Iii, Kenneth S Macdonald, Hultgren, Kristin & Duffy, Emmett, 2009, The sponge-dwelling snapping shrimps (Crustacea, Decapoda, Alpheidae, Synalpheus) of Discovery Bay, Jamaica, with descriptions of four new species, Zootaxa 2199, pp. 1-57 : 9-11

Synalpheus belizensis Anker and Tóth

Material examined. Jamaica: Non-ovigerous individual, ovigerous female ( VIMS 08JAM0501,02), Columbus Park, Discovery Bay, from canals of Xestospongia proxima . Non-ovigerous individual, ovigerous female ( VIMS 08JAM1101,02), Pear Tree Bottom Reef, from canals of X. proxima . 4 non-ovigerous individuals, ovigerous female ( VIMS 08JAM8401,05), wall off Rio Bueno, from canals of X. proxima . 3 nonovigerous individuals, ovigerous female ( VIMS 08JAM8701-03), wall off Rio Bueno, Jamaica, from canals of X. proxima . MaxCL ovigerous female: 5.58 mm. MaxCL non-ovigerous individual: 4.67 mm.

Color. Pale milky in appearance, distal end of major chelae orange; embryos and ovaries bright yellow. Hosts and ecology. In Jamaica, this species has only been found inhabiting sponges of the genus Xestospongia . The types from the Belize Barrier Reef came from an unidentified cryptic sponge. In Jamaica, this species is often found cohabitating with other members of the Synalpheus paraneptunus Coutière complex, viz. S. bocas Anker and Tóth and S. duffyi Anker and Tóth.

Distribution. Belize ( Anker and Tóth 2008); Jamaica (this study).

PLATE 2. A, Synalpheus bocas ovigerous female (08JAM7404) from Xestospongia proxima, Rio Bueno , Jamaica. B, Synalpheus bocas ovigerous female (08JAM7504) from Xestospongia proxima, Rio Bueno , Jamaica. C, Synalpheus carpenteri ovigerous female (08JAM6113) from Agelas cf. clathrodes, Columbus Park, Discovery Bay , Jamaica. D, Synalpheus corallinus ovigerous female (08JAM7001) from Hyattella intestinalis, Dairy Bull Reef , Jamaica.

Remarks. Synalpheus belizensis belongs to a complex of morphologically similar species that includes S. paraneptunus , S. bocas , S. duffyi , S. brevidactylus Anker and Tóth , and S. riosi Anker and Tóth. Although S. belizensis females always have bright yellow embryos or mature ovaries, the color of these parts in the morphologically similar S. bocas ranged from bright green to yellow, therefore, making these two species difficult to distinguish by color pattern alone, i.e., without careful morphological examination. Synalpheus belizensis may be most reliably distinguished from S. bocas by the presence of a scaphocerite blade in the former species, although the blade was often vestigial (or missing on one side) in larger individuals of S. belizensis . Although the diagnosis of S. belizensis in Anker and Tóth (2008) states that the scaphocerite does not have a blade, this is presumably an error, for the figure of the holotype plainly shows a blade, and the authors mention the scaphocerite blade in other parts of the manuscript (including the key). Synalpheus belizensis can be distinguished from the remaining members of the S. paraneptunus group by the uropodal exopod bearing a single fixed tooth anterior to the movable spine on the lateral margin (vs. two or more in other species); and the third maxilliped armed with a crown of eight to nine spines (vs. six or fewer in other species).