Isostichopus fuscus

Isostichopus fuscus (Ludwig, 1875) Figs 1 I’–O’, 3A–D, 4D, 5B, 9, 10D, 11D, 19–21; Tables 1–3 Stichopus fuscus Ludwig, 1875: 97–98. Stichopus badionotus – Selenka 1867: 316 (partim). — Clark 1922: 56 (partim). Stichopus fusus – Théel 1886: 256. Typographic error. Stichopus fuscus – Ludwig 1898: 5, pl. 1 figs 1–5. — Clark 1910: 350; 1922: 45 (as unidentifiable form). — Deichmann 1937: 163; 1938: 363. — Steinbeck & Ricketts 1941: 410. Isostichopus fuscus – Deichmann 1958: 280–281, pl. 1 figs 1–3. — Hickman 1998: 56, appendix a, p. 65. — Solís-Marín et al. 2009: 138, fig. 44. — Borrero-Pérez & Vanegas-González 2022: 329– 334. — Purcell et al. 2023: 144–145. Original name Stichopus fuscus Ludwig, 1875. Current status Isostichopus fuscus (Ludwig, 1875). Name-bearing type Syntype ZMH E.2689. Type locality Manchalilla, Ecuador; proposed by Deichmann (1958) instead of Patagonia (probably wrong), as Ludwig (1898) reported the species in this locality. Diagnosis Reticulated, uniform chocolate brown, with stains or reddish color in the background with yellowish large wart-like dorsal papillae (Figs 1 I’–O’, 21); large tables with a circular spire well developed in the cloaca (Figs 11D, 19C, 20F); distributed in the East Pacific Ocean (Fig. 5B); mtDNA divergence from other species of the genus> 6.1% in COI-Fr1 (barcoding region),> 9.5% in COI-Fr2 and> 5.2% in 16S (Table 2). Material examined EAST PACIFIC – Mexico • 3 specs, Selenka’s syntype of S. badionotus (L = 180 to 220 mm); Guerrero, Acapulco; A. Agassiz, collector number 239 leg.; MCZ HOL-743 • 1 spec. (L = 140 mm); Sonora, Pelican Point; 30 Jul. 1969; B. Burch leg.; USNM E21411 • 1 spec. (L = 210 mm); Guerrero, Acapulco; 4–6 Aug. 1982; Hassler exped.; MCZ HOL-742 • 2 specs (L = 210–230 mm); Oaxaca, Puerto Escondido; 25–26 Mar. 1940; E.F Ricketts and J Steinbeck leg.; MCZ HOL-2113 • 1 spec.; Guerrero, Zihuanejo Bay, Playa Las Gatas; depth 3 m; 14 Oct. 1995; M. Olivares leg.; rocky bottom; ICML-UNAM 5.13.52 • 1 spec.; Nayarit, Punta Mita, Corral del Mangle; 21.7700583° N, 105.5174277° W; depth 5 m; 29 Jul. 1995; C. Vizcarra leg.; rocky bottom; ICML-UNAM 5.13.54 • 2 specs; Michoacán, Faro de Bucerías; 18.3468861° N, 103.5119833° W; depth 4 m; 20 Dec. 1993; J. Mendoza. leg.; rocky bottom; ICML-UNAM 5.13.55 • 2 specs; Oaxaca, Puerto Angelito; 15.6522222° N, 96.48527777° W; depth 4 m; 25 Jan. 1995; S. Ramírez leg.; rocky bottom; ICML-UNAM 5.13.63 • 1 spec.; Michoacán, Lázaro Cárdenas municipality, Pichilinguillo; 18.0719444° N, 102.76° W; depth 6 m; Dec. 2006; rocky bottom; ICML-UNAM 5.13.69 • 4 specs; Baja California Sur, west coast of Mexico, Magdalena Bay; 24.5138889° N, 112.0066666° W; depth 4 m; 18 Oct. 1987; F. Solís-Marín leg.; rocky bottom; ICML-UNAM 5.13.73 • 1 spec.; Guerrero, Zihuanejo Bay, Playa La Pedregosa Grande; 17.6183333° N, 101.5311111° W; depth 5 m; 20 Oct. 1992; J. Vargas leg.; rocky bottom; ICML-UNAM 5.13.77 • 2 specs; Sonora, Laguna de Yavaros, La Barra pier; 31 Oct. 1970; Orbe leg.; rocky bottom; ICML-UNAM 5.13.78 • 1 spec.; Colima, Manzanillo, Peña Blanca; 4 Oct. 1993; G. Ramírez leg.; ICML-UNAM 5.13.110 • 1 spec.; Colima, Revillagigedo Archipelago, Socorro Island; 18.7249167° N, 110.9392222° W; depth 15–17 m; 29 Nov. 1997; H. Reyes leg.; ICML-UNAM 5.13.115 • 1 spec.; Nayarit, Isla Isabel; 21.8425° N, 105.8861111° W; 20 Nov. 1997; J. Carballo leg.; rocky bottom; ICML-UNAM 5.13.121 • 1 spec.; Guerrero, Caleta de Campos, El Corralón; 18.0697833° N, 102.7438333° W; depth 3 m; 2 Mar. 2010; F. Solís-Marín leg.; ICML-UNAM 5.13.126 • 1 spec.; Michoacán, Lázaro Cárdenas municipality, Mexcalhuacán; 18.049° N, 102.6591666° W; depth 6–11 m; 4 Mar. 2010; F. Solís-Marín leg.; ICML-UNAM 5.13.127 • 1 spec.; Colima, Manzanillo, Canal de Tepalces; 19.0047944° N, 104.2572305° W; depth 1 m; 15 Aug. 2010; E. Celaya leg.; ICML-UNAM 5.13.128 • 1 spec.; Jalisco, Puerto Vallarta, Majahuitas; 20.5066667° N, 105.3855° W; depth 15 m; 23 Jan. 2010; F. Solís-Marín leg.; ICML-UNAM 5.13.130. – USA • 1 spec. (L = 140 mm); California, San Diego; 4–6 Sep. 1982, 18–22 Aug. 1982; Hassler exped.; MCZ HOL-758. – Colombia • 1 spec. (L = 180 mm); Chocó, Piedra Bonita; 5.59403° N, 77.5034° W; depth 12 m; 18 Oct. 2016; G. Borrero-Pérez, Riscales 2016 leg.; rocky bottom, among rocks; INV EQU4323 • 1 spec. (L = 115 mm); same data as for preceding; INV-EQU4324 • 1 spec.; Chocó, Chicocora; 6.68023° N, 77.4305° W; depth 12 m; 18 Oct. 2016; G. Borrero-Pérez, Riscales 2016 leg.; rocky bottom, among rocks, IfRIC154R; INV TEJ1960 • 1 spec. (L = 120 mm); Chocó, Nuqui; 5.5691389° N, 77.52369444° W; depth 10 m; 18 Sep. 2003; G. Borrero-Pérez, Nuqui 2003 leg.; rocky bottom, among rocks; INV EQU2746 • 1 spec. (L = 40 mm); Chocó, Piedra de Oswaldo; 5.54429° N, 77.51554° W; depth 15 m; 19 Apr. 2016; J. Vanegas-González, Riscales 2016 leg.; rocky bottom, among rocks; INV EQU4229 • 1 spec. (L = 145 mm); Chocó, Punta Arusí; 5.61111° N, 77.48512° W; depth 6 m; 24 Apr. 2016; J. Vanegas-González, Riscales 2016 leg.; rocky bottom, among rocks; INV EQU4230 • 1 spec. (L = 130 mm); Chocó, Parguera; 5.60989° N, 77.50409972° W; depth 15.5 m; 20 Apr. 2016; J. Vanegas-González, Riscales 2016 leg.; rocky bottom, among rocks; INV EQU4231 • 1 spec. (L = 170 mm); Chocó, Punta Faro; 6.82467° N, 77.68996° W; depth 12 m; 25 Oct. 2016; G. Borrero-Pérez, Riscales 2016 leg.; rocky bottom, among rocks; INV EQU4321 • 1 spec. (L = 165 mm); same data as for preceding; INV EQU4322 • 1 spec. (L = 130 mm); Chocó, Piedra de Rodrigo; 6.78391° N, 77.69358° W; depth 19 m; 26 Oct. 2016; G. Borrero-Pérez, Riscales 2016 leg.; rocky bottom, among rocks; INV EQU4325 • 1 spec.; Malpelo Island; 29 Feb. 1972; C. Birkeland leg.; USNM E23715. – Panama • 1 spec.; Panama, Taboguilla Island; 8.8005667° N, 79.52332777° W; depth 10 m; 31 Aug. 2015; H. Lessios and A. Calderón leg.; rocky bottom, hidden under rocks; IfTa210; Tiss-IfTa210 • 1 spec. (L = 150 mm); same data as for preceding; IfTa211; USNM 1659483 • 1 spec. (L = 200 mm); same data as for preceding; 17 Aug. 2015; IfIP322; USNM 1659482 • 1 spec. (L = 150 mm); same data as for preceding; IfTa213; USNM 1682794 • 1 spec. (L = 155 mm); same data as for preceding; If212; MBMLP-If212 • 1 spec.; Gulf of Panama; 7.6666667° N, 78.75° W; 6 Sep. 1972; ICML-UNAM 5.13.98. – Ecuador • 1 spec. (a piece of tegument); Galapagos Islands, San Cristobal Island; depth 15 m; 1 May 1993; P. Humann leg.; USNM 1017480 • 1 spec. (L = 57 mm); Galapagos Islands, James Island; 21 Jan. 1938; RV Velero III, Hancock Pacific exped.; MCZ HOL-1921 • 1 spec.; Galapagos Islands, Devil’s Crown; depth 15 m; 17 Aug. 1998; Hickman, Cleveland leg.; 98- 502; UF 9112 • 1 spec.; Galapagos Islands, Champion; 17 Aug. 1998; Hickman, Cleveland leg.; 98-503; UF 9651 • 1 spec.; Galapagos Islands, San Cristobal, Kicker Rock; depth 21 m; 5 May 1996; Hickman, Cleveland leg.; under rock; 96 19; UF 9672. – Peru • 2 specs; Isla Lobos de Afuera; 6.9666667° S, 80.75° W; depth 5 m; 10 Jun. 1999; F. Solís-Marín leg.; rocky bottom; ICML-UNAM 5.13.72. GULF OF CALIFORNIA – Mexico • 1 spec. (L = 210 mm); La Paz, El Mogote; 21–22 Mar. 1940; E.F Ricketts and J Steinbeck leg.; MCZ HOL-2115 • 6 specs; Sinaloa, Mazatlán Bay, Isla de Venados; 23.3980556° N, 106.4722222° W; depth 7 m; 15 Feb. 1979; M.E. Caso. leg.; ICML-UNAM 5.13.23 • 1 spec.; Baja California Sur, La Paz Bay, Canal San Lázaro, Salvierra wreck; 24.3852778° N, 110.3008333° W; depth 20 m; 15 Aug. 1996; R. Murillo. leg.; rocky bottom; ICML-UNAM 5.13.56 • 1 spec.; Baja California Sur, La Paz Bay, Puerto Balandra; 24.3284028° N, 110.3344222° W; depth 2 m; 28 Apr. 1969; G. Mendez leg.; rocky bottom; ICML-UNAM 5.13.57 • 1 spec.; Baja California Sur, La Paz Bay, Los Islotes; 24.5858333° N, 110.3886111° W; depth 6 m; 20 Mar. 1993; C. Sánchez leg.; rocky bottom; ICML-UNAM 5.13.64 • 1 spec.; Baja California Sur, La Paz Bay, Isla Espíritu Santo, San Gabriel Bay; 24.4405167° N, 110.3744416° W; depth 3 m; 25 Nov. 1963; M. Beltrán leg.; rocky bottom; ICML-UNAM 5.13.67 • 2 specs; Baja California Sur, La Paz Bay, Puerto Balandra; 24.3283333° N, 110.3341666° W; depth 3 m; 29 Apr. 1969; M.E. Caso leg.; rocky bottom; ICML-UNAM 5.13.81 • 1 spec.; Sinaloa, Mazatlán Bay, Isla de Lobos; 23.2302778° N, 106.4619444° W; 17 Nov. 1998; L. Carballo leg.; ICML-UNAM 5.13.122 • 1 spec.; Sonora, San Carlos; 27.0156806° N, 111.0915° W; 16 Jan. 2010; F. Solís-Marín leg.; ICML-UNAM 5.13.129 • 2 specs; Baja California, Bahía de Calamajue; 29.775° N, 114.2333333° W; May 1998; D. Gonzalez leg.; ICML-UNAM 5.13.116 • 1 spec.; Baja California Sur, South of Isla Santa Catalina; 25.5148333° N, 110.778° W; depth 20–30 m; 24 Aug. 2008; F. Solís-Marín leg.; rocky bottom; ICML-UNAM 5.13.125. Description EXTERNAL APPEARANCE. Medium to large size species up to 280 mm (Solís-Marín et al. 2009), preserved specimens examined 40–230 mm long (n = 19). Body loaf-like, length/width ratio 3.0 ±0.9 (n = 19, 1.6–5.8). Living specimens convex in cross section, some specimens somewhat quadrangular, rounded in both anterior and posterior parts (Fig. 21). Body wall firm and 2–7 mm thick (MCZ HOL-743, L = 220 mm). Anus supra-terminal, circular and surrounded by large papillae. Mouth directed ventrally, encircled by a collar of large papillae and 20 peltate tentacles; tentacles 10–12 mm long, shield 9–10 mm wide with deep 3–4 mm indentions (MCZ HOL- 743, 220 mm). Dorsal papillae large, not variable in shape, wart-like, even in small specimens (INV EQU4229, L = 40 mm, 2 mm high and 2.5 wide; MCZ HOL-743, L = 220 mm, 2–4 mm high and 4–5 mm wide), irregularly arranged, fewer on the dorso-lateral side (Figs 19A, 21). Lateral row papillae large and rounded, sharply defining the dorsal and ventral surface in both juveniles and adults, in living or preserved specimens (Figs 19A, 21). Preserved specimens usually with prominent papillae. Ventral surface densely covered with cylindrical pedicels, arranged in three longitudinal rows (Fig. 21). COLOR AND BODY WALL APPEARANCE