Holothuria (Halodeima) inornata Semper, 1868

Honey-Escandón, Magali & Solís-Marín, Francisco A., 2018, A revision of Holothuria (Halodeima) kefersteinii (Selenka, 1867) and the revival of Holothuria inornata Semper, 1868 from sea cucumbers collected in Mexico and Central America, Zootaxa 4377 (2), pp. 151-177 : 167-168

Holothuria (Halodeima) inornata Semper, 1868

Holothuria inornata Semper, 1868: 252 ; Lampert 1885: 83; Théel 1886: 215; Ludwig 1889 –92: 329; Fisher 1907: 672; Deichmann 1938: 365; Caso 1957: 325; 1961: 325; 1962: 315; 1965: 279; 1979: 201–202; Brusca & Thomson 1975: 46. Holothuria (Holothuria) inornata .—Panning 1934: 33.

Holothuria kefersteini .— Boone 1933: 156; Steinbeck & Ricketts 1941: 408; Van der Heiden & Hendrickx 1981: 74; Solís- Marín et al. 1997: 256; Hickman 1998: 52; Cintra-Buenrostro et al. 1998: 342; Lawrence & Sonnenholzner 2004: 241; Purcell et al. 2012: 44, 149, 179.

Ludwigothuria kefersteini .— Deichmann 1958: 312.

Holothuria (Ludwigothuria) kefersteini .— Hickman 1998: 63.

Holothuria (Halodeima) kefersteini .— Rowe 1969: 138; Maluf 1988: 157; Maluf 1991: 359; Samyn 2003: 35; Solís-Marín et al. 2005: 132; Honey-Escandón et al. 2008: 67.

Holothuria (Halodeima) inornata . — Solís-Marín et al. 2009: 104; 2013: 19, 24; 2014: 444, 446–447; Prieto-Ríos et al. 2015: 156–161.

Material examined. A total of 418 specimens were analyzed. Catalog numbers, number of specimens, localities and dates of collection are recorded in Table 3.

Types. Natural History Museum, London syntype no. 84.3.8.18 ; Zoological Museum of University of Hamburg syntype no. E.2575.

Type locality. Acapulco , Mexico ( Semper, 1868).

Diagnosis. Color of live specimens brilliant, uniformly dark red dorsally, sometimes lighter at the base of the warts; red can vary from medium, almost orange to deep red. Ventrum and ventral tube feet, as well as tentacles, black or deep gray, tips light. Dorsal tube feet with tables with reduced spiny base, without perforations or with two to four or more perforations but not forming a complete ring; spire of four pillars, one cross beam and a Maltese cross crown. Also, large straight rods, with few or several distal perforations; sometimes, also perforated rosettelike rods, as supporting structures to the tube feet, almost half the size of the straight perforated rods. In papillae on warts, curved, smooth perforated or non-perforated supporting rods as well as rosette-like perforated rods.

Description. Color in alcohol uniform dark red on the bivium; dorsal and ventral tube feet the same color as the skin, sometimes darker; suckers sometimes lighter; warts sometimes brighter; generally trivium darker than bivium, almost black or dark grey. Older preserved specimens same pattern of coloration but brown or dark brown instead of red. Tentacles dark deep brown, almost black, sometimes speckled with white. Body wall covered by scattered, cylindrical tube feet, more numerous and larger on the ventral than on the dorsal surface. Dorsally, four or more not well defined rows of papillae on warts. Mouth terminal, surrounded by seventeen to twenty tentacles; anus terminal. Body wall up to 5 mm thick.

Dorsal body wall with tables with reduced spiny disc, without perforations or with two to four or more perforations not forming a complete ring; smaller specimens, with disc almost complete. Spire of four pillars, one cross beam and a Maltese cross crown. Dorsal tube feet with tables similar to those of body wall; and large, straight rods, as long as four or more times the width of tables, with few or several distal perforations; perforated rosettelike rods, almost the same size as the tables, also present as supporting structures. Endplates present. In the papillae on warts, curved, smooth perforated or non-perforated supporting rods might be present. Ventral body wall with tables with reduced base, without a ring of perforations, occasionally with two or three holes; spire of four pillars, one cross beam and a Maltese cross crown. Ventral tube feet with tables similar to those of body wall and perforated pseudo-plates mainly with two big central holes; endplates present.

Longitudinal muscles divided, completely attached. Calcareous ring with radial plates as long as 1.5 to 3 times the length of interradial plates. One or two well developed Polian vesicles, rarely more, 1/12 to 1/3 of the body length, rarely shorter. Two to 26, rarely one, short (less than 1/12 the body length) stone canals in one tuft, on the right side of dorsal mesentery, sometimes on both sides. Cuvierian tubules present, apparently non-expellable, short (less than 1/12 body length) and few in number (two to ten, approximately), easily detachable. Gonad unbranched in one cluster. Right respiratory tree extending total length of body.

Remarks. The species is easily recognized by the color and the cover of sand. The rods from the tube feet and papillae are of two kinds: straight, distally multi-perforated (a strong taxonomic character separating this species from H. kefersteinii ); and curved, almost non-perforated supporting rods (similar to those in the podia of H. kefersteinii ). The rosette-like perforated rods, sometimes present in the papillae, are also a useful taxonomic character since H. kefersteinii does not present them.

Known geographical distribution. In the states of Baja California, Baja California Sur, Sonora, Sinaloa, Nayarit, Jalisco, Colima, Michoacán, Guerrero, Oaxaca, Chiapas, and Revillagigedo Islands in Mexico; El Salvador, Nicaragua ( Deichmann 1938); Costa Rica, Panamá, Perú and Galápagos Islands.

Ecology. Always found beneath rocks, covered with a thin layer of fine sand; larger organisms also found next to rocks, over sand, covered with fine or coarse debris mimicking the bottom. The great majority of the large organisms have a symbiotic relationship with Holothuriophilus trapeziformis , a small crab that lives in the cloaca ( Campos et al. 2012).