Paulayellus gustavi, Martins & Tavares, 2018

Martins, Luciana & Tavares, Marcos, 2018, A new genus and species of Sclerodactylidae (Echinodermata: Holothuroidea: Sclerothyoninae) from the Pacific coast of Panama, and assignment of Neopentamera anexigua to Sclerothyoninae, Zootaxa 4429 (1), pp. 157-164 : 161-163

Paulayellus gustavi gen. nov., sp. nov.

( Figs. 3–4 )

Type material. Gulf of Panama, Panama (8. 2745-79.0771), 25–27 m, 9.iv.2004, holotype 50 mm ( FLMNH 4550). Permanent slides of body wall ossicles ( MZUSP 1619).

Comparative material examined. Apentamera lepra Deichmann, 1941 — Isla Partida, Gulf of California, Baja California, Mexico (28° 55’ N, 113° 5.6’ W), 45m, 8.iii.1936, holotype 28 mm ( LACM 329.4 ) . Isla Partida , Gulf of California, Baja California, Mexico, (28° 55’ N, 113° 5.6’ W), 82m, 8.iii.1936, paratypes 16 mm ( LACM 1936-71.2 ) .

Thandarum hernandezi Martinez & Brogger, 2012 — Argentine Sea, Mejillon II Expedition, (36°09’S; 55°53’W), 15m, 15.ix.2009, 30 mm ( MZUSP 1616 ).

Temparena chuni ( Ludwig & Heding, 1935) —Valdivia, 2 spm 6–7 mm (ZMUC HOL 323). Cape of Good Hope (3433'S 1821'E), 318 m: slides of the holotype (MNHN-IE-2005 6561; MNHN-IE-2005 6562) [all originally labeled Cucumaria chuni Ludwig & Heding, 1935 ].

Sclerothyone veligera ( Ludwig & Heding, 1935) —Cape of Good Hope (3433'S 1821'E), 318 m. slides of the holotype (MNHN-IE-2005 6566; MNHN-IE-2005 6567; MNHN-IE-2005 6568) [all originally labeled as Cucumaria veligera Ludwig & Heding, 1935 ].

Neopentamera anexigua Deichmann, 1941 —Holotype (LACM E.1937-85.2). USNM E 21478 (for details see above under N. anexigua )

Diagnosis. Body fusiform. Tube feet arranged in double rows restricted to ambulacral region. Ten tentacles, ventral-most pair smaller. Calcareous ring plates undivided and united only at base, with posterior processes entire. Body wall with knobbed buttons, plates and cups. Tentacles with rods. Introvert with plates. Tube feet with supporting rods, end plate small.

Etymology. This species is named in honor of Gustav Paulay in recognition for his contributions to the systematics of Echinoderms.

Description. Body U-shaped, slightly upturned at both ends ( Fig. 3A ), rough to touch. Color brown in ethanol. Anal papillae present ( Fig. 3B ). Tube feet arranged in double rows, restricted to ambulacra. Retractor muscles attached to radial plates, tapering distally ( Fig. 3C ). Plates of calcareous ring short, undivided, notched anteriorly; posterior processes undivided. Interradial plates tapering gently anteriorly, notched distally; base concave. Radial and interradial plates united at base only ( Fig. 3D ). Body wall ossicles comprising four-holed knobbed buttons (60–90 µm long, Fig. 4A–B ), perforated plates (180–250 µm long, Fig. 4C ), and cups knobbed in outline (45–60 µm long, Fig 4D–E ). Body wall and introvert with cups (70–80 µm long) and perforated plates (240–560 µm long, Fig 4F ). Tentacles rods curved, perforated (250–300 µm long, Fig. 4G ). Tube feet with perforated, curved rods (100–120 µm long, Fig. 4H ), knobbed plates (100 µm long), supporting rods irregular in outline and rudimentar spire (100–150 µm long, Fig. 4I ), end plates small (100-120 µm long).

Type locality. Gulf of Panama, Panama, 25–27 meters depth.

Remarks. Paulayellus gustavi gen. nov., sp. nov. superficially resembles the Sclerodactylinae Apentamera lepra Deichmann, 1941 , with which it shares the presence of knobbed buttons, plates and cups in the body wall. However, while in P. gustavi gen. nov., sp. nov. the radial and interradial plates of the calcareous ring are typically Sclerothyoninae , i.e., the plates are united at base only, in A. lepra the radial and interradial plates of the calcareous ring are united along their entire length, as in the remaining Sclerodactylinae genera. Paulayellus gustavi gen. nov., sp. nov. can be further differentiated from A. lepra in having tube feet provided with rods, whilst A. lepra has tables instead of rods in the tube feet.

Figures

FIGURE 3. (A–D) Paulayellus gustavi gen. nov., sp. nov., hOlOtype (FLMNH 4550). (A) lateral view Of the bOdy. (B) Anal papillae (white arrOw). (C) RetractOr muscle (white arrOw). (D) Detail Of the calcareOus ring. Scale bars: A, 1 cm. B, 0, 2 cm. C–D, 0,1 cm.

FIGURE 4. (A–I) Paulayellus gustavi gen. nov., sp. nov., hOlOtype (FLMNH 4550). SEM phOtOmicrOgraphs Of the Ossicles. (A–B) TOp and lateral views, respectively, Of buttOns frOm bOdy wall. (C) PerfOrated plate frOm bOdy wall. (D–E) Cups and (F) plates frOm intrOvert. (G) ROds frOm tentacles and (H–I) suppOrting rOds frOm tube feet. Scale bars: A–B, 30 µm. C, 100 µm. D–E, 30 µm. F, 100 µm. G, 200 µm. H, 20 µm. I, 50 µm.