Ophelina juhazi, Wiklund, Helena, Neal, Lenka, Glover, Adrian G., Drennan, Regan, Muriel Rabone, & Dahlgren, Thomas G., 2019

Wiklund, Helena, Neal, Lenka, Glover, Adrian G., Drennan, Regan, Muriel Rabone, & Dahlgren, Thomas G., 2019, Abyssal fauna of polymetallic nodule exploration areas, eastern Clarion-Clipperton Zone, central Pacific Ocean: Annelida: Capitellidae, Opheliidae, Scalibregmatidae, and Travisiidae, ZooKeys 883, pp. 1-82 : 1

Ophelina juhazi sp. nov. Fig. 13 A–G

Material examined.

NHM_1073 (holotype) NHMUK ANEA 2019.7132, coll. 26 Feb. 2015, 12°06.93N, 117°09.87W, 4100 m http://data.nhm.ac.uk/object/f7330230-224b-49e7-aa80-41e8654ea087.

Type locality.

Pacific Ocean, CCZ, 12°06.93N, 117°09.87W, depth 4100 m, in mud between polymetallic nodules.

Description.

This species is represented by a single specimen 17 mm long and 0.5 mm wide for 29 chaetigers. Ventral and lateral grooves distinct along whole length of body. Live specimens translucent, with orange-red gut ( Fig. 13A ); colour in alcohol yellow to light tan ( Fig. 13B ). Body very smooth, iridescent, annulations indistinct (best observed in first five to seven anterior chaetigers). All chaetigers elongated, first five chaetigers only slightly crowded.

Prostomium conical (longer than wide), with distinct, tear-shaped terminal palpode ( Fig. 13C, D ). Eyes not observed. Nuchal organs observed as slits, laterally on posterior part of prostomium, without pigmentation.

Branchiae absent. Parapodia biramous, embedded in lateral grooves; parapodia small conical lobes, best observed on anterior seven chaetigers ( Fig. 13E ); no distinct pre- or postchaetal lobes observed. Chaetae all slender, smooth capillaries ( Fig. 13F ), very few in both rami. Notochaetae mostly longer than neurochaetae.

Anal tube attached; narrow, cylindrical structure, symmetrical, smooth (no cirri observed) and distally slightly narrowing ( Fig. 13G ).

Genetic data.

GenBank MN217443 for 16S and MN217504 for 18S. COI was unsuccessful for this specimen, no identical GenBank matches for 16S or 18S. In our phylogenetic analyses, Ophelina juhazi sp. nov. is sister to O. curli sp. nov. ( Fig. 23 ).

Remarks.

Morphologically similar to Ophelina curli sp. nov. and to Ophelina nematoides ; see Remarks under Ophelina curli sp. nov. for details.

Ecology.

Found in polymetallic nodule province of the eastern CCZ.

Etymology.

Named in honor of Bob Juhazi, Oiler onboard RV Melville on the AB01 ABYSSLINE cruise in 2013.

Figures

Figure 13. Ophelina juhazi sp. nov. holotype (specimen NHM _ 1073). A Live images, whole specimen (center) with detail of anterior (left) and posterior (right) B Lab image, whole specimen C Lab image, anterior and prostomium D Lab image, detail of palpode E Lab image, anterior and parapodia (stained, pp = parapodia) F Lab image, detail of capillary chaetae G Lab image, posterior and anal tube (stained). Morphological features in plates C, E, G have been outlined with a very fine white line to improve clarity of those features. Scale bars: 1 mm (B); 100 μm (D); 50 μm (F); 1 mm (E).

Figure 23. Phylogenetic analysis of Opheliidae. 50 % majority rule tree from the Bayesian analyses using 18 S and 16 S, with posterior probability values on nodes. Twenty-nine taxa from GenBank were included, and Capitellidae and Echiura was chosen as outgroup following the annelid phylogeny of Weigert and Bleidorn (2016).