Epitomapta simentalae, Solis-Marin, Francisco Alonso, onejeros-Vargas, Carlos Andres, Andrea Alejandra Caballero-Ochoa, & Arriaga-Ochoa, Julio Adrian, 2019

Solis-Marin, Francisco Alonso, onejeros-Vargas, Carlos Andres, Andrea Alejandra Caballero-Ochoa, & Arriaga-Ochoa, Julio Adrian, 2019, Epitomaptasimentalae sp. n., a new species of apodous sea cucumber from the Central Eastern Pacific coast of Mexico (Echinodermata, Holothuroidea, Apodida), ZooKeys 817, pp. 1-9 : 1

Epitomapta simentalae sp. n. Figs 1, 2, 3, 4

Type material.

Holotype ICML-UNAM 5.169.0, 19 mm total length (TL), Caleta, Acapulco Bay, Guerrero, Mexico, Pacific Ocean 16°49.812'N, 99°59.062'W, 10 m depth, 8 May 2008, coll. F. A. Solís-Marín.

Paratypes: USNM 1114315, 10 specimens, same data as the holotype; ICML-UNAM 5.169.1, 11 specimens, same data as the holotype; ICML-UNAM 5.169.2, 63 specimens, Caleta, Acapulco Bay, Guerrero, Mexico, Pacific Ocean 16°49.812'N, 99°59.062'W, 10 m depth, 28 October 2006, coll. F. A. Solís-Marín, Y. Yerye, Honey-Escandón, M., A. Martínez Melo; ICML-UNAM 5.169.3, 20 specimens, Caleta, Acapulco Bay, Guerrero, Mexico, Pacific Ocean 16°49'N, 99°59'W, 4 m depth, 2 March 2006, coll. F. A. Solís-Marín, C. S. Frontana Uribe; ICML-UNAM 5.169.4, 27 specimens, Caleta, Acapulco Bay, Guerrero, Mexico, Pacific Ocean 16°49'N, 99°59'W, 9 m depth, 27 September 2006, coll. F. A. Solís-Marín, B. Urbano, M. A. Torres; ICML-UNAM 5.169.5, 5 specimens, Caleta, Acapulco Bay, Guerrero, Mexico, Pacific Ocean 16°49'N, 99°59'W, 8 m depth, 21 March 2009, coll. F. A. Solís-Marín and J.A. Díaz-Jáuregui.

Type locality.

Caleta, Acapulco Bay, Guerrero, Mexico, Pacific Ocean 16°49.812'N, 99°59.062'W.

Diagnosis.

Body wall smooth, lacking papillae or oval bumps. Tentacles 12, each with two or three pairs of digits and a terminal digit; up to six sensory cups on each tentacle. One Polian vesicle. Stone canal single, unbranched. Anchor and anchor plates of one kind, large, anchors usually exceeding 120 µm in length, plates exceeding 100 µm in length. Miliary granules numerous, in form of C-shaped rods with enlarged ends and O-shaped ossicles present only in the longitudinal muscles. Tentacle ossicles curved spiny rods with perforated ends.

Holotype description.

19 mm total length (TL).When preserved is uniformly whitish, body wall translucent when expanded (Fig. 1); color in life pink to light purple. Gonads well developed, yellowish in preserved specimens (Fig. 1). Anchors (Fig. 2B) project through body wall. Tentacles 12, each with two to three pairs of digits and a terminal digit; digits increase in length distally, and terminal digit is longest. Inner (oral) surfaces of tentacles with double row of well-developed sensory cups; up to six sensory cups on each tentacle (Fig. 3). Ciliated funnels of various shapes (Fig. 4) occur on the body wall, not on the mesenteries. There are two longitudinal rows of ciliated funnels, each row attached to one side of one longitudinal muscle. Polian vesicle single. Stone canal single, unbranched. Calcareous ring simple, well developed (Fig. 2A); the radial pieces (Fig. 2Ar) have a cavity in the central region more conspicuous than that in inter-radial pieces (Fig. 2Ai).

Ossicles. Body wall deposits, anchors, and anchor plates of one kind (Fig. 2 B–C). Anchors and plates at anterior, middle and posterior body wall essentially similar, although developmental stages of these ossicles more numerous posteriorly; anchors of this region (in a ventral view) have the right arm slightly more elongated than the left. Anchors average 120 µm in length. Arms carry up to six conspicuous teeth. Stock unbranched, but equipped with numerous small sharp projections (Fig. 2B). Anchor plates elongated, approximately oval, with numerous toothed perforations. Anchor plates average 100 µm in length and 90 µm in greatest width (Fig. 2C). Miliary granules numerous, present only in the epithelium covering the longitudinal muscles, highly variable in shape, but generally the miliary granules tending to be enlarged; C and O-shaped bodies are distinguishable Granules up to approximately 30 µm in length (Fig. 2E). Stems of tentacles with ossicles similar to miliary granules of longitudinal muscle epithelium but tending to be slightly smaller. In tentacle digits spiny rods of up to 90 µm length, with perforated ends (Fig. 2D).

Paratype variations. Specimens ranges from 4-43 mm TL. Sensory cups vary in number, fewer (2-3) in smaller specimens (4-15 mm TL).

Ethymology.

Epitomapta simentalae sp. n. is named in honor of Dr Delia Rosalba Simental Crespo, a scientist, entrepreneur and echinoderm enthusiast, who supports research programs and marine expeditions providing passion, funding, equipment, and travel support to scientists who are involved in research and conservation efforts related to the echinoderms in the Mexican marine waters.

Ecology.

Epitomapta simentalae sp. n. occurs at 4-10 m depth, burrowed approximately 2 cm deep in in well-aerated quartz sand.

Reproduction.

Epitomapta simentalae sp. n. is a gonochoric species; females have lecithotrophic eggs between 140 and 150 μm in diameter; ripe gonads occupy about 80% of the celomic cavity. Neither brooding nor external sexual dimorphism was observed.

Geographical distribution.

Known only from Caleta, Acapulco Bay, Guerrero.