HOLOTHURIANS 267 



(Key to Species cont'd.) 



11. Dorsal spicules laterally branched rods up to 120 ^m long and rosettes 38 to 54 ^m long; in ventral 

 body wall, small oval grains and rods without lateral projections (Fig. 3d); color light chocolate brown, 



usually mottled with grayish white; body length up to about 20 cm (Fig. 7d) Actinopyga mauritiana (Quoy and Gaimard) 

 Dorsally, in single sp)ecimen examined, laterally branched rods up to 102 ^m long, rosettes to 77 ^m 

 long; ventral spicules rods with lateral edges smooth, roughened, or finely branched, no oval grains 

 (Fig. 3c); dorsal color yellowish white with three broad, irregular, transverse bands of brownish black, 

 ventral surface uniformly yellowish white with bright yellow pedicels; body length 5.5 cm (Fig. 7e) 



Actinopi/ga ?rriauritiana juvenile 



12. Calcareous ring ribbon-like, with radial pieces shorter than broad and interradials similar but tending 

 to be curved; podia comparatively few, in double rows confined to ambulacra or, dorsally, more or 



less scattered 13 



Calcareous ring stout and relatively strong, not ribbon-like, radial plates either as long as broad or 



longer than broad, not curved; podia crowded ventrally, numerous, and scattered dorsally 14 



13. Spicules in body wall tables with spire ending in four to six long, simple or bifurcate, horizontal spines 

 or four short, vertical spines, together with smooth rods with simple, branched, or perforated ends 

 (Fig. 3e); 20 tentacles; color translucent pinkish white in life, opaque white in alcohol; body length up 



to 25 cm (Fig. 6d) Labidodemas semperianum Selenka 



Spicules in body wall incomplete or complete tables, the latter with spires of four (usueilly) or three pil- 

 lars crowned with three or more forked spines or simple circlet of fine spines, also spiny or smooth 

 dichotomously branched, X-shaped rods (Fig. 7f); up to 18 tentacles; color in life bright, translucent 

 canary yellow with very fine, closely spaced brown specks and scattered small brown spots, in alcohol 

 tannish yellow; body length up to 2.5 cm (Fig. 6b) Labidodemas ?semperianum Selenka 



14. Spicules in body wall tables with reduced disk, rosettes and small perforated plates (Fig. 2a); color 



uniformly purplish black; body length up to about 30 cm (Fig. 6g) Holothuha (Halodeima) atra Jaeger 



Spicules in body wall tables with well-developed, smooth or spinous disk and buttons, complete or 



incomplete 15 



15. Buttons typically complete and regular; disk of tables with smooth rim 16 

 Buttons commonly incomplete and asymmetrical or reduced to knobbed bars; disk of tables with 



smooth or spinous rim 19 



16. Buttons flat, thin, oval, with four or more pairs of small holes and with distinct median optical discon- 

 tinuity; perforate plates in pedicels (Fig. 2d); color uniformly rich olive brown or reddish brown, lighter 



on ventral side; body length up to 10 cm (Fig. 6f) Holothuha (Plafyperona) difficilis Semper 



Buttons not flat and thin; color not uniformly brown 17 



17. Buttons 75 to 93 nm long, with three pairs of holes; disk of tables squarish, 78 to 95 ^m wide; per- 

 forated rods in pedicels up to 233 fim long (Fig. 2f); color yellowish brown, with irregular, transverse 

 bands or blotches of purplish brown dorsally; body length up to 15 cm (Fig. 7c) 



Holothuha (ThymiosyciaJ impafiens (Forsskal) 

 Buttons, tables, and rods smaller 18 



18. Buttons up to 78 ixm long, with three (usually) or four pairs of holes; disk of tables 62 to 68 ^m 

 wide, spire ending in 20 or more teeth; pedicel rods up to 27 ^m long (Fig. 2e); color white to tan 

 with two longitudinal rows of brown spots dorsally and very fine, reddish brown spots scattered over 



all surfaces; body length up to about 20 cm (Fig. 7a, b) Holothuha (Thymiosyciaj arenicola Semper 



Buttons up to 78 ^m long, with three to five pairs of holes, disk of tables 62 to 75 ^m wide, spire 



ending in fewer than 20 teeth; pedicel rods up to about 190 urn long (Fig. 2c); color in life yellowish 



brown, with yellow-tan dorsal papillae; body length up to 30 cm (Fig. 6e) Holothuha (Thymiosycia^ hilla Lesson 



19. Tables with smooth but sometimes uneven rim, spire reduced; buttons reduced, often as knobbed bars 

 (Fig. le); color mottled cream and brown or gray, with some yellow, base of dorsal papillae with red 



ring; body length to about 20 cm (Fig. 6h) Holothuha (Mertensiothuha) pervicax Selenka 



Tables well-developed, top of spire with eight to 12 spines, disk usually spinous; some buttons regular 



with three pairs of holes, others incomplete and asymmetrical (Fig. 2b); color purplish brown to 



almost black; body length up to about 20 cm (Fig. 6i) Holothuha (Mertensiothuha) leucospilota (Brandt) 



(Key to Species continued on page 271.) 



