Neopentamera anexigua Deichmann, 1941

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: 158-160

publication ID

https://doi.org/10.11646/zootaxa.4429.1.8

publication LSID

lsid:zoobank.org:pub:A7B0734A-5F12-4724-9A9F-324BA1BE9BD4

persistent identifier

http://treatment.plazi.org/id/03B387C9-FF89-D132-FF73-E6E6FEC8F991

treatment provided by

Plazi

scientific name

Neopentamera anexigua Deichmann, 1941
status

 

Neopentamera anexigua Deichmann, 1941 

( Figs. 1–2View FIGURE 1View FIGURE 2)

Material examined. Conception Bay, Gulf of California, Baja California, Mexico 15.iii.1938, holotype 20 mm ( LACMAbout LACM E.1937-85.2)  . Sonora, Gulf of California , Mexico 28.xi.1980, 1 spm 20 mm ( USNMAbout USNM E 21478)  .

Diagnosis. The present diagnosis is based on Deichmann's (1941) and is amended herein to include previously unused characters from the calcareous ring. The amended diagnosis is as follows: Body fusiform. Tube feet arranged in double rows restricted to ambulacral region. Ten tentacles, ventral-most pair smaller. Calcareous ring with undivided radial and interradial plates united at the base and posterior processes divided, broken into few large pieces (about 3-4 pieces). Posterior process of radial plate twice as long as radial plate. Ossicles. Body wall knobbed buttons and plates; tentacles with rods; introvert with plates; tube feet with supporting rods. End plate star-shaped.

Description. The following is in addition to other descriptions thus far. Body U-shaped slightly upturned at both ends ( Fig. 1A View Figure ). Color brown in ethanol. Tube feet arranged in double rows restricted to the ambulacra. One Polian vesicle, madreporite circular and long stone canal ( Fig. 1D View Figure ). Radial plates of the calcareous ring short, undivided and notched anteriorly; posterior processes broken up into few large pieces ( Fig. 1C View Figure ). Interradial plates pointed anteriorly. Radial and interradial plates united at base ( Fig. 1B View Figure ).

Body wall ossicles comprising four holed knobbed buttons (40–60 µm long, Fig. 2A View Figure ), perforated plates (100– 120 µm long, Fig. 2B–D View Figure ). Introvert with perforated plates. In the tentacles perforated tentacle rods and rosettes (20–60 µm long, Fig. 2E View Figure ). In the tube feet perforated rods (100–120 µm long, Fig 2F View Figure ) and a star shapedend plate.

Remarks. Thandar (1989) recognized three subfamilies in the Sclerodactylidae  : Cladolabinae  Heding & Panning, 1954 (sclerodactylids with 15–20 tentacles), Sclerodactylinae (sclerodactylids with 10 tentacles and radial and interradial plates of the calcareous ring united along their entire length) and Sclerothyoninae  Thandar, 1989 (sclerodactylids with 10 tentacles and radial and interradial plates of the calcareous ring united at the base). Smirnov (2012) that elevated Sclerothyoninae  to familial status, whereas Miller et al. (2017) have seemingly treated Sclerodactylidae  to encompass the Sclerothyoninae  .

Originally, Neopentamera anexigua  was described in Cucumariidae Ludwig, 1894  . Panning (1949: 456) erected the subfamily Sclerodactylinae (within Cucumariidae  ), whose diagnosis included the presence of 10 tentacles, calcareous ring with undivided radial and interradial plates and posterior processes divided, broken into few large pieces (about 3-4 pieces). Panning (1949) included nine genera in Sclerodactylinae, among which Neopentamera  . Pawson & Fell (1965) assigned familial status to Sclerodactylinae, Sclerodactylidae  . Thandar (1989) created the subfamily Sclerothyoninae  , which differed from Sclerodactylinae in having radial and interradial plates of the calcareous ring united at base only (whilst the radial and interradial plates are united along the entire length in Sclerodactylinae). The examination of the holotype of N. anexigua  revealed that the radial and interradial plates of its calcareous ring are actually united at the base only ( Fig. 1B View Figure ), as typically found in the Sclerothyoninae  . Therefore, Neopentamera anexigua  can no longer be assigned to the Sclerodactylinae and is herein transferred to the Sclerothyoninae  . This conclusion was reached independently in an unpublished dissertation by Arumugam (2011) brought to our attention by Prof. A. S. Thandar. Neopentamera  differs from the others Sclerothyoninae  genera by the presence of knobbed buttons and plates in the body wall, and absence of tables and cups.

LACM

Natural History Museum of Los Angeles County

USNM

Smithsonian Institution, National Museum of Natural History