Travisia zieglerae, 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

Travisia zieglerae sp. nov. Fig. 29 A–G

Material examined.

NHM_140 (paratype) NHMUK ANEA 2019.7162, coll. 11 Oct. 2013, 13°45.50N, 116°41.91W, 4080 m http://data.nhm.ac.uk/object/ed10356b-32a0-4b45-9fe3-c56fbc696e87; NHM_188 NHMUK ANEA 2019.7170, coll. 14 Oct. 2013, 13°57.43N, 116°30.10W, 4130 m http://data.nhm.ac.uk/object/c8a0ef70-e7f7-4605-bf78-dc54ed9151eb; NHM_241 NHMUK ANEA 2019.7163, coll. 16 Oct. 2013, 13°48.70N, 116°42.60W, 4076 m http://data.nhm.ac.uk/object/5c0ac0b7-60cc-473e-a23b-2f49a40540f4; NHM_356 NHMUK ANEA 2019.7164, coll. 17 Oct. 2013, 13°45.21N, 116°29.12W, 4128 m http://data.nhm.ac.uk/object/8d2cbf0e-6522-403d-a58a-905fb13c70d6; NHM_364 NHMUK ANEA 2019.7165, coll. 19 Oct. 2013, 13°55.98N, 116°42.977W, 4182 m http://data.nhm.ac.uk/object/ef6e520f-7ef5-4ff9-87b5-985b8576271f; NHM_748B (paratype) NHMUK ANEA 2019.7166, coll. 20 Feb. 2015, 12°32.23N, 116°36.25W, 4425 m http://data.nhm.ac.uk/object/db527676-1030-4bf0-b28d-2382825bc6bf; NHM_753 NHMUK ANEA 2019.7167, coll. 20 Feb. 2015, 12°32.23N, 116°36.25W, 4425 m http://data.nhm.ac.uk/object/393203b1-cb80-4185-9e40-fca6e1b6fe34; NHM_760 NHMUK ANEA 2019.7168, coll. 20 Feb. 2015, 12°32.23N, 116°36.25W, 4425 m http://data.nhm.ac.uk/object/d3e8ec3c-d7f3-4908-b315-84f3758aecc1; NHM_792 NHMUK ANEA 2019.7169, coll. 20 Feb. 2015, 12°32.23N, 116°36.25W, 4425 m http://data.nhm.ac.uk/object/5d30a61b-5894-484f-b79a-df1cd4268ec1; NHM_909 (paratype) NHMUK ANEA 2019.7171, coll. 23 Feb. 2015, 12°34.28N, 116°36.63W, 4198 m http://data.nhm.ac.uk/object/5f570dab-4b56-4f74-b126-ed6ceab344e3; NHM_970 NHMUK ANEA 2019.7172, coll. 23 Feb. 2015, 12°34.28N, 116°36.63W, 4198 m http://data.nhm.ac.uk/object/4ccb364c-35f4-458c-9c71-6f77e71493ca; NHM_1097 NHMUK ANEA 2019.7173, coll. 26 Feb. 2015, 12°06.93N, 117°09.87W, 4100 m, http://data.nhm.ac.uk/object/939ba16d-b844-49ca-a740-bb42f039cc11; NHM_1310 NHMUK ANEA 2019.71745,coll. 01 Mar. 2015, 12°15.44N, 117°18.13W, 4302 m http://data.nhm.ac.uk/object/16844478-de27-448c-9acb-057835026447; NHM_1311 NHMUK ANEA 2019.7175, coll. 01 Mar. 2015, 12°15.44N, 117°18.13W, 4302 m http://data.nhm.ac.uk/object/192cbbb3-680b-4bcd-9cc4-a420f42af578; NHM_1431 (holotype) NHMUK ANEA 2019.7176, coll. 03 Mar. 2015, 12°27.26N, 116°36.77W, 4137 m http://data.nhm.ac.uk/object/fd6bab0e-0cda-4b42-808f-a6006d409535; NHM_1543 (paratype) NHMUK ANEA 2019.7177, coll. 06 Mar. 2015, 12°30.38N, 116°29.07W, 4244 m http://data.nhm.ac.uk/object/c78cc5fd-ca98-43b0-a0fb-8804fb606c71; NHM_1873 NHMUK ANEA 2019.7178, coll. 13 Mar. 2015, 12°02.496N, 117°13.03W, 4094m, http://data.nhm.ac.uk/object/24409a12-2a50-4689-80dc-902cdeb5af69; NHM_1883 NHMUK ANEA 2019.7179, coll. 13 Mar. 2015, 12°02.49N, 117°13.03W, 4094 m, http://data.nhm.ac.uk/object/9e8c22f7-a94b-45ed-a1d0-cae287a7ac2d; NHM_1911 NHMUK ANEA 2019.7180, coll. 13 Mar. 2015 12°02.49N, 117°13.03W, 4094 m http://data.nhm.ac.uk/object/489dd5a6-2c68-416b-9a06-ed773d4791d6; NHM_2019 NHMUK ANEA 2019.7181, coll. 16 Mar. 2015, 12°03.03N, 117°24.28W, 4235 m http://data.nhm.ac.uk/object/2684a5f8-b4d4-4bcb-b386-65775506cf87; NHM_2024 NHMUK ANEA 2019.7182, coll. 16 Mar. 2015, 12°03.03N, 117°24.28W, 4235 m http://data.nhm.ac.uk/object/cf54f81e-5836-4684-94dc-151f589ebab4.

Type locality.

Pacific Ocean, CCZ, 12°27.26'N 116°36.77'W, depth 4137 m, in mud between polymetallic nodules.

Additional material examined.

Travisia glandulosa McIntosh, 1879, holotype BMNH 1921.5.1.2431 and specimen of Monro (1930), Travisia gravieri McIntosh, 1908, holotype BMNH 1921.5.1.2429.

Description.

This species is represented by 21 specimens. It is a small species 1.2-7.5 mm long and 0.25-0.8 mm wide for 21-24 segments, 19 or 20 of which chaetigerous and 2-4 posterior-most achaetigerous. Preserved specimens pale yellow ( Fig. 29A ), live specimens translucent ( Fig. 29B )

Holotype in good condition, 6 mm long and 0.8 mm wide (at the widest point). Body robust, compact, grub like, anteriorly (commonly on chaetigers 1-7) somewhat enlarged then tapering posteriorly and relatively slender. Body surface rugose, with transverse rows of small squarish lobes.

Prostomium short, smooth, conical ( Fig. 29C ). Peristomium trapezoidal, rugose, with squarish papillae larger and then in subsequent segments, two transverse rows observed using Shirlastain A ( Fig. 29C ). Mouth as a broad transverse slit extending to chaetiger 1 ( Fig. 29D ).

Branchiae absent. Parapodia biramous, located on row with largest lobes, both rami well separated ( Fig. 29C, E ). Parapodial lappets present, observable from chaetiger 2 and well developed from chaetiger 8. Chaetigers in anterior (inflated) half distinctly triannulate, with three transverse rows of small, squarish lobes, subsequent segments becoming less distinctly annulated, with the last four achaetigerous segments uniannulate; lobes always largest on the ventral most row. Interramal sense organs present, best observed on stained specimen ( Fig. 29E ). Chaetae all long, smooth, slender capillaries ( Fig. 29F ).

Pygidium short, thick (only slightly longer wide), ventrally with keel-like very thick lobe. In distal view ( Fig. 29G ) with circlet of about 10 smaller, thinner lobes located dorsally to large ventral keel-like lobe.

Shirlastain pattern.

Prostomium stains strongly and stain is retained even after one week. Interramal sense organs observed as darkly red stained spots ( Fig. 29E ).

Morphological variation.

Number of segments is slightly variably and appears to be linked to size, with the smallest specimens possessing 21 segments (19 of which chaetigerous), while the largest specimen possessed 24 segments (20 of which chaetigerous). Body shape remains mainly consistent, although some specimens were slightly thinner or thicker. Thick, keel-like ventral lobe on pygidium observed consistently, but the detection of slenderer lobes differs (probably an artefact of preservation) and some occasionally appear inflated ( Fig. 29G ).

Remarks.

Differences between the known Travisia species and the species delineated herein are discussed in the Remarks section for Travisia sp. (NHM_1244), see below.

Genetic data.

GenBank MN217470-MN217490 for 16S and MN217512 for 18S. Travisia zieglerae sp. nov. fall within a clade consisting of the other Travisia species in this study as well as other Travisia species on GenBank and the taxon Neolipobranchus sp., a result similar to Martinez et al. (2014), suggesting a paraphyletic genus Travisia ( Fig. 32 ).

Ecology.

Found in polymetallic nodule province of the eastern CCZ.

Etymology.

Named in honor of Amanda Ziegler, member of the science party of the ABYSSLINE AB02 cruise onboard the RV Thomas G. Thompson.

Figures

Figure 29. Travisia zieglerae sp. nov. A Lab image, whole specimen, pre-stain (holotype [specimen NHM _ 1431]) B Live images, whole specimens (specimen NHM _ 1911 [left], specimen NHM _ 188 [right]) C Lab image, lateral anterior, (holotype, stained, pr = prostomium, pp = parapodial lappets) D Lab image, distal anterior, (holotype, stained, m = mouth) E Lab image, lateral posterior, (holotype, stained, pp = parapodia, io = interramal organs) F Detail of capillary chaeta (paratype NHM _ 140) G Lab image, pygidium, distal view (left) and lateral view (right), with pygidial features outlined in a fine white line (holotype, stained, vl = ventral lobe). Scale bar: 1 mm (A).

Figure 32. Phylogenetic analysis of Scalibregmatidae and Travisiidae. 50 % majority rule tree from the Bayesian analyses using 18 S and 16 S, with posterior probability values on nodes. Twenty taxa from GenBank were included, and Opheliidae was chosen as outgroup following the annelid phylogeny of Weigert and Bleidorn (2016).