Isostichopus macroparentheses

Isostichopus macroparentheses (Clark, 1922) Figs 1 P’–Q’, 3A–D, 4E, 5B, 9, 10E, 11E, 22–24; Tables 1–3 Stichopus macroparentheses Clark, 1922: 61–63, pl. 1 figs 1–7. Stichopus megaparentheses – Clark 1922: 63. Typographic error. Stichopus macroparentheses – Deichmann 1926: 21; 1930: 82–83, pl. 5 figs 37–43. — Clark 1933: 110 (as S. macraparentheses, typographic error). Isostichopus badionotus – Deichmann 1957: 4–5; 1963: 106. — Miller & Pawson 1984: 54. — Cutress 1996: 105, 112. — Pawson et al. 2010: 34–35. Stichopus macroparenthesis – Deichmann 1957: 4–5. Typographic error. Isostichopus macroparentheses – Pawson 1976: 374, fig. 1d. — Solís-Marín et al. 1998: 524. — Hendler & Pawson 2000: 282. — Laguarda-Figueras et al. 2001: 28, fig. 11a–d; 2005: 119. — Alvarado & Solís-Marín 2013: 650. Original name Stichopus macroparentheses Clark, 1922. Current status Isostichopus macroparentheses (Clark, 1922). Name-bearing type Holotype MCZ HOL-921, MCZ HOL-225 (ossicle slide of the holotype); paratype MCZ HOL-1214. Type locality Montego Bay, Jamaica. Diagnosis C-shaped ossicles> 90 µm long on average; disc tables in dorsal papillae and body wall completely reduced in adults (Figs 10E, 23A); tridimensional spheres and straight/spiky rods in the respiratory tree (Fig. 23F); semi-translucent and smooth body wall; color not variable, background of dorsal side light yellow-brown, with irregularly arranged blurred large and small darker brown spots (Figs 22A, C, 24); mtDNA divergence from other species of the genus>16.2% in COI-Fr1 (barcoding region),> 16.3% in COI-Fr2 and>9.5% in 16S (Table 2). Material examined Holotype JAMAICA • L = 50 mm, contracted; Montego Bay, Bogue Island; 18.46908° N, 77.931086° W; Mar. 1912; H.L. Clark leg.; MCZ HOL-921 • ossicle slide of the holotype; same data as for holotype; MCZ HOL-225. Paratype USA • 1 spec. (L = 65 mm); Florida, Tortugas, Bird Key; 24.6185° N, 82.8854° W; Jun. 1917; Carnegie Institute, Tortugas Laboratory leg.; MCZ HOL-1214. Other material GULF OF MEXICO – Mexico • 1 spec.; Veracruz, Isla Lobos; 21.465° N, 97.22866° W; depth 2–7 m; 16 Mar. 2011; F. Solís-Marín leg.; coral, rocky bottom; ICML-UNAM 5.88.1 • 1 spec.; Veracruz, Isla Lobos; 21.4726667° N, 97.23116° W; depth 12 m; 17 Mar. 2011; F. Solís-Marín leg.; coral, rocky bottom; ICML-UNAM 5.88.2 • 1 spec.; Veracruz, Isla Lobos; 21.4541667° N, 97.22500° W; depth 1.5 m; 13 Mar. 1976; coral, rocky bottom; ICML-UNAM 5.88.3. CARIBBEAN SEA – Mexico • 1 spec.; Quintana Roo, Puerto Morelos, off Rodman shipyard; 20.87472° N, 86.85083° W; depth 2 m; 1 Jul. 1995; F. Solís-Marín leg.; rocky bottom; ICML-UNAM 5.88.0 • 1 spec.; Quintana Roo, Akumal Bay; 20.39375° N, 87.31426° W; depth 2.5 m; 25 May 2012; F. Solís-Marín leg.; rocky bottom; ICML-UNAM 11053. – US Virgin Islands • 1 spec. (L = 60 mm); St. Croix Island, Rod Bay; 17.733761° N, 64.614086° W; depth 0.5 m; 17 Jul. 1990; R. Aronson leg.; USNM E40833. – British Virgin Islands • 1 spec. (L = 135 mm); Guana Island; 18.472111° N, 64.576794° W; depth 2 m; 1 Jun. 1997; A. Kerr leg.; USNM E47524. – Antigua and Barbuda • 1 spec. (L = 80 mm); Antigua Island, English Harbor; 17° N, 61.7667° W; 7 Jan. 1918; C. Nutting leg.; USNM E4391 • 1 spec. (L = 70 mm); same data as for preceding; USNM E22322 • 1 spec. (L = 50 mm); same data as for preceding; USNM 1283366. – Curaçao • 1 spec.; Carmabi Marine Research Station; 12.12177° N, 68.96964° W; depth 3 m; 18 Feb. 2020; G. Paulay leg.; reef shelf; BCUR-0532; UF20352. – Belize • 1 spec. (L = 20 mm); Tobacco Cay; 16.945997° N, 88.060744° W; depth 2 m; 10 Jun. 2016; L. Geyer and G. Borrero-Pérez leg.; rocky bottom, ImrBe99; USNM 1659484 • 1 spec. (L = 40 mm); Carrie Bow Cay; 16.803074° N, 88.081939° W; depth 2 m; 12 Jun. 2016; A. Hiller and G. Borrero-Pérez leg.; rocky bottom, ImrBe107; USNM 1659485 • 1 spec. (L = 30 mm); Belize, Carrie Bow Cay; 16.80295° N, 88.08145° W; depth 1–2 m; Apr. 1975; M. Carpenter leg.; USNM E18627 • 1 spec. (L = 25 mm); Carrie Bow Cay, near transect along wall of trough behind fore reef crest; 16.80295° N, 88.08145° W; depth 18 m; 22 Mar. 1979; G. Hendler leg.; USNM 1021529. Description EXTERNAL APPEARANCE. Small to medium size species, preserved specimens up to 135 mm long (n = 11, range 20–135 mm, holotype: 50 mm, paratype: 65 mm). Body loaf-like, length/width ratio 3.1± 0.5 (n = 11, range 2.4–4.1, holotype 3.8, paratype 4.1). Holotype (contracted) and paratype rounded posteriorly and anteriorly (Fig. 22A, C), similar to living specimens, which are convex/subcylindrical in cross section (Fig. 24). Body wall soft and not very thick (paratype: 0.5–1 mm; USNM E47524 (L = 135 mm): 2–4 mm). Anus supra-terminal, circular and not surrounded by large papillae. Mouth directed ventrally, encircled by a collar of medium sized papillae (paratype: 2 mm high; holotype: retracted). Nineteen large peltate tentacles in the holotype (retracted) and paratype (3–4 mm long, 2.5–3 mm wide shield, with 0.5 mm deep indentations); 20 tentacles in the largest specimen USNM E47524 (6–7 mm long; 4–4.5 mm wide shield). Large live and preserved specimens with flat and inconspicuous dorsal and lateral papillae (Fig. 24F, J–K) (USNM47524: less than 1 mm high and 2 to 5 mm wide at the base). Juvenile live specimens with medium to large dorsal papillae, rounded or pointed, ending in a thin tip, scattered irregularly; lateral papillae similar in shape to the dorsal ones, but smaller and less obvious (Fig.24A–E). Papillae in the holotype and paratype small (Fig. 22A, C). Lateral rows not sharply defining the dorsal and ventral surface in either juveniles or adults, in living or preserved specimens (Figs 22, 24). Ventral surface in both juveniles and large specimens densely covered with cylindrical pedicels, arranged in three longitudinal rows (Figs 22, 24); most of the pedicels retracted and longitudinal rows not evident in the largest preserved specimen (USNM E47524). COLOR AND BODY WALL APPEARANCE. Body wall surface smooth and semi-translucent (Figs 1, 22, 24) (see also Clark 1922: 62). Color not variable, living specimens light yellow-brown in the background on the dorsal side with irregularly arranged blurred big and small darker brown spots that do not coincide with the papillae; papillae lighter, with the distal end almost white, or at least lighter than the base of the papillae, yellow according to Clark (1922) (Fig. 1 P’–Q’). Ventral surface lighter than dorsal with small spots in the same dorsal pattern, pedicels translucent white, end plate of darker brown (Fig. 24). Preserved specimens similar to live ones in color, tentacles with light brown tubes and darker shields (Fig. 24F–I). Holotype and paratype uniform whitish on the dorsal and ventral surfaces, with slightly darker tentacles (Fig. 22A, C). Living juveniles (20 mm long) similar in color as adults, tentacles translucent white (Fig. 24A–E). INTERNAL ANATOMY (based on MCZ HOL-1214 (paratype, L = 65 mm), USNM E47524 (L = 135 mm) and MCZ HOL-921 (holotype, L = 50 mm, mostly deteriorated)). Calcareous ring diameter 7 mm in the 65 mm specimen and 11 mm in the largest 135 mm one; radial elements almost as long as wide (L = 65 mm: 2 mm wide, 1.5 mm long; L = 135 mm: 5 mm wide, 4.2 mm long), with four anterior small lobes and small posterior projections that are larger in the largest specimen (1.2 mm) (Fig. 4E); interradial elements pointed anteriorly and concave in the posterior margin, about half as wide as radial elements and somewhat shorter (L = 65 mm: 2.5 mm wide, 1.5 mm long; L = 135 mm: 2.5 mm wide, 3 mm long). Single and irregularly helical stone canal (L = 65 mm: 4 mm long; L = 135 mm: 10 mm long), attached to the mesentery, ending in a flat leaf-like madreporite, 2 mm wide in the largest specimen. Tentacle ampullae in the largest specimen 12–16 mm long, 2–3 mm long in the 65 mm specimen, and 1.5–2 mm in the holotype. One tube-like Polian vesicle in the 65 mm specimen and the holotype (both 6 mm long, 1 mm wide); two tube-like Polian vesicles in the largest specimen, one longer (15 mm long, 2.5 mm wide) than the other (9 mm long, 1.5 mm wide), streaked longitudinally, with spots and dark tips. Gonads found only in the holotype (Fig. 11E). Longitudinal muscles approximately 1.5 and 2.5 mm wide in the 65 mm specimen and the holotype, and 4 mm wide in the largest specimen (USNM E47524), divided and attached to the body wall medially and laterally. Respiratory trees insert to the cloaca arising from a common stem 13 mm long in the 135 mm specimen, the left tree extending with the intestine (L = 65 mm: 25 mm long; L = 135 mm: 65 mm long) and right tree free (19 mm and 45 mm long, respectively). OSSICLES (based on MCZ HOL-921 (holotype, L = 50 mm), MCZ HOL-225 (holotype permanent slide), MCZ HOL-1214 (paratype, L = 65 mm), USNM E47524 (L = 135 mm, SEM images (Fig. 22)); USNM 1659484 (juvenile, L = 20 mm) and USNM 1659485 (juvenile, L = 40 mm); juveniles only for dorsal papillae and body wall). Ossicles of the holotype are mostly deteriorated; however, some aspects of the remaining ossicles, the permanent slide MCZ HOL-225, and the description of Clark (1922), who only described the ossicles from papillae and pedicels, are included. Dorsal papillae with tables, thin C-shaped rods, perforated plates, and large, curved rods (Figs 10E, 22B, 23A). All types of ossicles present in all specimens, from 20 mm to 135 mm long. Numerous C-shaped rods, a few S-shaped ones, ranging from 91 to 155 (x = 133) µm long; 2–3 times as long as tables are high, usually abundant in the papilla tip, sometimes in the base; no obvious correlation with body length (Figs 9A, 10E). Numerous tables with notable changes in shape and size during growth. Tables in 20, 40 and 65 mm specimens 31 to 48 (x = 40) µm high and with large discs with smooth and wide margins 24–77 (x = 48) µm across the disc, characterized by one large central perforation, which appears as four large and symmetrical holes, without outer holes, or usually