Tetreres israeli, Chávez-López, 2022

Chávez-López, Yessica, 2022, New species of sabellariids (Annelida: Sabellariidae) from the Caribbean Sea and the Gulf of Mexico, European Journal of Taxonomy 831, pp. 109-148 : 139-142

Tetreres israeli sp. nov.

urn:lsid:zoobank.org:act:C1846882-4FD6-4BBF-AAD3-52C523251A89

Figs 18–19

Diagnosis

Outer paleae lanceolate, compressed with sharp tips, elongated and slender. Inner paleae cylindrical, smooth, with blunt tip. Two to four tentacular filaments per lobe.

Etymology

This species is named in memory of my grandfather Israel López, an exemplary man. The species name is a noun in the genitive case ( ICZN 1999, Art. 31.1.2).

Material examined

Holotype CARIBBEAN SEA • complete spec. (very damaged); Virgin Islands; RV Pillsbury , stn 1401; 18°51′ N, 65°04′ W; depth 4180 m; 12 Jul. 1972; UMML-22.1195 .

Paratype CARIBBEAN SEA • 1 spec.; same collection data as for holotype; UMML-22.1196 .

Description

BODY. Holotype complete (UMML-22.1195), very damaged, 40 mm long, 0.5 mm wide, four parathoracic segments, five abdominal segments ( Fig. 18A–D ).

OPERCULUM. Opercular disc oblique. Opercular crown with almost all opercular paleae broken ( Fig. 18B– C ). Outer paleae arranged in semicircles, seven paleae on left lobe, 18 on right ( Fig. 18B–F ). Inner paleae in short ventral line on each inner margin of opercular lobes, three paleae on left lobe, four on right ( Fig. 18B, F ). Outer paleae amber, lanceolate, compressed, 3 mm long. Blade six times as long as wide ( Fig. 19A–B ). Tip sharp, elongate, slender ( Fig. 19B ). Inner paleae amber, cylindrical, smooth, tip blunt ( Fig. 19C–D ). Opercular stalk orange to pale yellow, almost three times as long as wide ( Fig. 18B ). Opercular papillae not observed. One pair of nuchal hooks amber, long, robust, with short limbation, tip strongly curved ( Figs 18B , 19E ). In lateral view, nuchal hooks distally curved at angle of ~115° ( Fig. 19F ). Palps and median organ not observed. Tentacular filaments damaged, simple, slender; two tentacles on left lobe, four on right ( Fig. 18C ).

THORAX. First thoracic segment without cirrus or chaetae. Second segment with two triangular-shaped lateral lobes and paired branchiae.

PARATHORAX. With four segments, branchiae not seen. Notopodia with lanceolate and capillary chaetae. Neurochaetae capillary.

ABDOMEN. Abdominal segments yellowish, not very well defined. Neuropodia small, with capillary chaetae, ornamented with irregular thecal laminar extensions ( Fig. 19G–H ). Notopodia robust, uncini not seen.

Variation

Specimen incomplete 28 mm long, 4 mm wide, 3 abdominal segments ( Fig. 18E–F ).

Remarks

In the Caribbean Sea and the Gulf of Mexico, Tetreres varians (Treadwell, 1901) was the only species of the genus recorded. Tetreres israeli sp. nov. and T. varians differ mainly in the morphology of the outer blades, being lanceolate in T. israeli sp. nov. ( Fig. 19A–B ) and oblong in T. varians ( Augener 1906: pl. 7, fig. 131; Kirtley 1994: fig. 12.10.3a, d–f).

The morphology of the paleae of T. israeli sp. nov. resembles those of T. perryi Kirtley, 1994 (Northwest Atlantic). Both species have lanceolate outer paleae with elongate tips; however, T. perryi has outer paleae with transverse irregular thecae, whereas T. israeli sp. nov. has no transverse thecae.

Distribution

Only known from the type locality, Virgin Islands, at 4180 m depth ( Fig. 22 ).

Figures

Fig. 18. Tetreres israeli sp. nov., holotype (UMML-22.1195). A. Complete specimen, dorsal view. B. Anterior region, dorsal view. C. Anterior region, lateral right view. D. Anterior region, ventral view. E. Paratype (UMML-22.1196). F. Operculum of the paratype. Abbreviations: ip = inner paleae; nh = nuchal hooks; op = outer paleae. Numbers indicate the tentacular filaments. Scale bars: A, C–E = 2 mm; B = 1 mm; F = 0.5 mm.

Fig. 19. Tetreres israeli sp. nov., holotype (UMML-22.1195). A. Outer palea. B. Tip of outer palea. C. Inner palea. D. Tip of inner palea. E. Nuchal hook, ventral view. F. Nuchal hook, lateral view. G. Abdominal parapodium. H. Abdominal chaetae. Abbreviation = Li, limbation. Scale bars: A, E = 200 µm; B, D, G = 100 µm; C = 1 mm; F = 0.5 mm; H = 30 µm.

Fig. 22. Localities for studied specimens. A. Caribbean Sea and the Gulf of Mexico. B. South Florida. C. Southeastern Bahamas. The crosses indicate type localities of species previously recorded in the tropical Western Atlantic.