Gastrosaccinae

Wittmann, Karl J., 2009, Revalidation of Chlamydopleon aculeatum Ortmann, 1893, and its consequences for the taxonomy of Gastrosaccinae (Crustacea: Mysida: Mysidae) endemic to coastal waters of America, Zootaxa 2115, pp. 21-33 : 31

Key to the species of Gastrosaccinae with apically widened third male pleopod

(Updated and modified from Heard and Price, 2006)

1 Fifth pleonite dorsally with caudally projecting, articulated lobe ( Fig. 1 G). Endopod of uropod with mostly mediumsized to large spines (taking into account perspective shortening, c.f. Fig. 1 E, F) along inner margin—no additional set of small spines near statocyst. West Atlantic and East Pacific...................... Chlamydopleon Ortmann, 1893 … 5

- Fifth pleonite without postero-dorsal lobe; endopod of uropod with medium-sized to large spines along inner margin plus an additional set of small spines near statocyst. West Atlantic and East Pacific ................................................... ....................................................................................................................... Coifmanniella Heard & Price, 2006 … 2

2 Postero-dorsal margin of carapace with a pair of non-reflected (= backwards oriented as in Fig. 1 B, J) submedian lobes. Apical cleft (measured without laminae) is 8-14 % telson length. Gulf of Mexico, Caribbean, Bahamas......... ............................................................................................................................. Co. johnsoni ( W.M. Tattersall, 1937)

- Postero-dorsal margin of carapace with a pair of antero-dorsally reflected submedian lobes ..................................... 3

3 Apical cleft is 23–40 % telson length. Brazil (5–8°S), Puerto Rico, Virgin Islands... Co. merjonesi ( Bǎcescu, 1968)

- Apical cleft is less than 20 % telson length ................................................................................................................. 4

4 Lateral margins of telson armed with 4–12 subequal spines in continuous series. Pacific coast of Panama, West Atlantic (24°S–35°N; range extension to 24°S is reported above in material list for Ch. dissimile ) including Gulf of Mexico and Caribbean ....................................................................................... Co. mexicana ( W.M. Tattersall, 1951)

- Lateral margins of telson armed with 15–25 spines in discontinuous series of 6–8 larger spines with smaller spines between. Gulf of Mexico, Florida, Bahamas, Caribbean .......................................... Co. parageia ( Brattegard, 1970)

5 Rostrum reaching beyond eyestalks (excluding cornea). Postero-dorsal margin of carapace with subtriangular median lobe. Apical cleft is 10–16 % telson length. Exopod of third pleopod in the terminal male with bow, inner branch with inner stylet reaching to more than half length of distal segment. East Pacific continental coasts at 9–33°N .............................................................................................................................. Ch. banneri ( Bǎcescu, 1968)

- Rostrum usually short, rarely overreaching terminal margin of eyestalk. Apical cleft is less than 13 % telson length. West Atlantic................................................................................................................................................................. 6

6 Postero-dorsal margin of carapace with sinusoid median lobe ( Fig. 1 B). Exopod of third pleopod in the subterminal male with two setae on third segment ( Fig. 1 D). Equatorial coast of Brazil................. Ch. aculeatum Ortmann, 1893

- Postero-dorsal margin of carapace with (sub)triangular median lobe ( Fig. 1 J). Exopod of third pleopod in the subterminal male without setae on third segment ( Fig. 1 K). The same exopod in the terminal male without bow, inner branch with inner stylet reaching to less than half length of distal segment. West Atlantic (25°S–39°N) including Gulf of Mexico and Caribbean ..................................................................................... Ch. dissimile ( Coifmann, 1937)

Figures

FIGURE 1. Chlamydopleon aculeatum Ortmann, 1893, lectotype (A – D, F – H) and paralectotype (E): A, anterior body region of male; B, lobes at postero-dorsal margin of carapace; C, penis, lateral view on inner face; D, third pleopod of the subterminal male, lateral view on inner face; E, endopod of uropod, lateral; F, endopod of uropod, ventral; G, terminal portion of pleon, dorsal; H, detail of (G) showing tip of telson. — Subterminal males in Chlamydopleon dissimile (Coifmann, 1937), lectotype from Brazil (J, K) and specimen with total length of 7.7 mm from Georgia (L): J, lobes at postero-dorsal margin of carapace; K, terminal portion of exopod of third pleopod, lateral; L, outer branch of exopod of third pleopod. Abbreviations: b, blade; is, inner stylet; ob, outer branch; vp, ventral process.