Synalpheus bocas, Anker, Arthur & Tóth, Eva, 2008

Anker, Arthur & Tóth, Eva, 2008, A preliminary revision of the Synalpheus paraneptunus Coutière, 1909 species complex (Crustacea: Decapoda: Alpheidae), Zootaxa 1915, pp. 1-28: 17-18

publication ID

http://doi.org/ 10.5281/zenodo.184596

persistent identifier

http://treatment.plazi.org/id/03D987B8-5855-FFA1-FF1A-FEAEFC38FDF2

treatment provided by

Plazi

scientific name

Synalpheus bocas
status

n. sp.

Synalpheus bocas  n. sp.

( Figs. 10View FIGURE 10, 11View FIGURE 11, 14View FIGURE 14 E –H)

Type material. Panama, Caribbean coast. Holotype, breeding female, USNM 1116687, Bocas  del Boro, STRI Bay, in sponge Xestospongia rosariensis  , 5–15 m, coll. E. Tóth, 3 Sep 2003 [03-033a]. Paratypes: 2 nonbreeding specimens USNM 1116688, same collection data as for holotype [03-032]; 1 non-breeding specimen, USNM 1116689, same collection data as for holotype [03-033b]; 1 male, USNM 1116690, same collection data as for holotype [03-039]; 2 males, 2 breeding females, USNM 1116691, same collection data as for holotype [03-040]; 1 male, 1 breeding female, UP, same collection data as for holotype [03-041]; 1 breding female, 1 male, USNM 1116692, Bocas  del Toro, STRI Bay, 8–9 m, in sponge Xestospongia rosariensis  , coll. E. Tóth, 15 Jan 2006 [06- 714, one specimen dissected]; 1 breeding female, USNM 116693, Bocas  del Toro, Isla Colón, Punta Caracol, 1–3 m, in sponges, coll. A. Anker, I. Marin and A. Baeza, 28 Apr 2007 [07- 144 b, photo voucher]; 1 non-breeding specimen, USNM 1116694, same collection data as previous specimen [07- 141 b, photo voucher].

Diagnosis. Rostrum not lower than orbital hoods, rather broad at base, not particularly slender, subequal to orbital teeth, with subacute tip; orbital teeth triangular, broad at base, subacute; both rostrum and orbital teeth slightly up-turned distally; notches between orbital teeth and rostrum moderately deep, in-between V- and U-shaped. Antennular peduncles with second segment distinctly longer than wide; stylocerite overreaching distal margin of first segment. Antenna with basicerite bearing blunt, almost non-projecting distodorsal tooth; scaphocerite without blade. Third maxilliped with crown of eight-nine spine-like setae on tip of ultimate segment. Major chela with palm about 2.5 times as long as fingers; distodorsal tooth on palm not bulging, with anteriorly directed or slightly descendant acute point. Second pereiopod carpus with five segments, first carpal segment about four times length of second. Third pereiopod with propodus bearing eight spine-like setae (not including distal pair); dactylus stout. Uropodal exopod with two fixed teeth (including lateral tooth of diaeresis) and slender movable spine-like seta. Telson with longitudinal median depression and two pairs of very stout spine-like setae inserted anterior and posterior to mid-length, respectively; posterior margin broad, about half-length of anterior width, rounded (see Figs. 10View FIGURE 10, 11View FIGURE 11). For detailed description of general features of S. paraneptunus  species complex see Dardeau (1984) and Ríos & Duffy (2007).

Etymology. The new species’ name was derived from the first word of the type locality, Bocas  del Toro, Panama; “ bocas  ” (mouths in Spanish) was here used as noun in opposition.

Colour pattern. Whitish semitransparent, with reddish chromatophores distributed in diffuse bands over the entire body, more on abdomen; major chela pale beige, distal margin of palm and fingers pale brown (except for pale area surrounded by darker margin on dactylus), tips amber-yellow; ovaries or fresh brood green ( Fig. 14View FIGURE 14 E –H), exceptionally greenish yellow (one female from San Cristobal, Bocas  del Toro).

Size. – Largest male, CL 4.9 mm; largest breeding female, CL 5.8 mm (holotype female, CL 5.7 mm).

Type locality. Bocas  del Toro, Panama.

Distribution. Presently known only from Bocas  del Toro, Panama.

Life history. This presumably pair-living species occurs in several sponges in Bocas  del Toro. For instance, several sexual pairs of S. bocas  n. sp. frequently inhabit Xestospongia rosariensis Zea and Rützler, 1983  ( Fig. 15View FIGURE 15 C, D), often together with congeners, such as the pair-living S. dardeaui ( Ríos and Duffy, 2007)  and the eusocial S. rathbunae Coutière, 1909  . It also occurs in single sexual pairs in the sponge Xestospongia  sp. ( Fig. 15View FIGURE 15 E), which superficially is intermediate between Xestospongia proxima (Duchassaing and Michelotti, 1864)  and X. subtriangularis (Duchassaing, 1850)  , and perhaps also in Calyx podatypa  (E. Tóth, pers. obs.). The larvae of S. bocas  n. sp. appear to be pelagic (E. Tóth, pers. obs.).

Remarks. Synalpheus bocas  n. sp. differs from all previous species, viz. S. paraneptunus  , S. duffyi  n. sp., S. riosi  n. sp., and S. brevidactylus  n. sp. by the consistent absence of a blade on the antennal scaphocerite ( Fig. 10View FIGURE 10 A); the presence of only two teeth on the uropodal exopod ( Fig. 10View FIGURE 10 G); the rostrum being subequal in length to the orbital teeth ( Fig. 10View FIGURE 10 A); and the third maxilliped distally armed with a crown of eight or nine spine-like setae (vs. at most six in the other species) ( Fig. 10View FIGURE 10 C). In life, S. bocas  n. sp. can be distinguished from S. duffyi  n. sp. and S. brevidactylus  n. sp. (the only two species with known colour patterns) by the presence of diffuse bands of reddish chromatophores on the abdomen and in some areas of the carapace. It also differs from S. duffyi  n. sp. by its much larger size in adults (see Table 1).

USNM

Smithsonian Institution, National Museum of Natural History