Terebellides

Terebellides sp. 1

Figures 11D, 35 A–B, 37; Tables 1, 2

Material examined. One specimen (NHMD-231440, Table 1).

Description

Measurements and general body features. Complete and well preserved specimen, 29 mm long and 2.5 mm wide (Fig. 35 A−B); body tapering posteriorly with segments increasingly shorter and crowded towards pygidium. Prostomium compact; very large tentacular membrane surrounding mouth, with typical buccal tentacles with expanded tips. SGI as an expanded structure below tentacular membrane. Lateral lappets on SGIII–VII (TC1–5).

Table 1. Locality and collecting data, museum registration numbers and reference to figures, of all Terebellides specimens described in this work. Country names and coordinates are copied from original museum labels.

…continued on the next page

Table 1. (continued)

…continued on the next page

Table 1. (continued) Angola (Off 130 “ “ 22-12-1950 17º13’S 11º42’E 75 1 NHMD-231444 – paratypes Cunene river) “ 131 “ “ 22-12-1950 17º13’S 11º42’E 100 1 NHMD-231445 – paratypes “ 132 “ “ “ 17º13’S 11º27’E 200 1 NHMD-231447 – paratypes MNCN non-type; Congo 16-2 this work N’Kossa 2003 5°16.839’S 11°33.966’E 150 1 – 16.01/18585 SEM MNCN non-type; “ 17-1 “ “ “ 5°16.365’S 11°33.655’E 110 1 – 16.01/18586 SEM MNCN “ NK0300E(B) “ “ 2015 5º16.4240’S 11º34.0065’E 158 2 – non-type 16.01/18587 MNCN non-type; 19C–F, “ N1S 0500S “ “ “ 5º19.4803’S 11º35.8724’E 137 1 – 16.01/18588 SEM 20A–F MNCN “ N1S 300S “ “ “ 5º20.7549’S 11º36.3353’E 136 1 – non-type 16.01/18589 MNCN non-type; “ NK0500S(A) “ “ “ 5º16.7202’S 11º33.8665’E 167 1 – 19A–B 16.01/18590 SEM Terebellides kirkegaardi sp. nov. original new campaign/oil country station-sample reference date longitude latitude depth specs registration registration Remarks Figures field number number Cameroon Kirkegaard 21A, (Bota at 61 Galathea 01-12-1950 n.d. n.d. 8–9 1 NHMD-231439 – holotype (1959) 22B Victoria) NHMD- “ “ “ “ “ “ “ “ 35 “ paratypes 22A, C-F 636923 NHMD- paratype; “ “ “ “ “ “ “ “ 1 “ 23A–D 636924 SEM NHMD- paratype, “ “ “ “ “ “ “ “ 1 “ 24A–G 636925 SEM

…continued on the next page

Table 1. (continued) NHMD- “ “ “ “ “ “ “ “ 1 “ paratypes 636926 MNCN 26A–D, Congo 11_2 this work N’Kossa 2003 5°22.708S 11°27.627E 545 1 – non-type; SEM 16.01/18591 27A–D Kirkegaard Angola 135 Atlantide 17-03-1946 7º55’S 12º38’E 235–460 2 NHMD-231437 – paratypes (1959) Kirkegaard “ 133 “ 1950 17º13’S 11º27’E 320 2 NHMD-231448 -– paratypes 25C (1959) Terebellides nkossa sp. nov. original new station- campaign/oil country reference date longitude latitude depth specs registration registration Remarks Figures sample field number number non-type; Kirgegaard Sierra Leone 51 Atlantide 31-1-1945 7º14’N 12º57’W 108 1 NHDM-231434 – labelled as T. (1959) af. nkossa MNCN Gabon AYM 34-1 this work Ayol 2011 1º19.82’ 8º43.8’ 43 3 – paratype 16.01/18592 MNCN “ AYM 34-2 “ Ayol “ “ “ “ 3 – paratype 16.01/18593 MNCN “ AYM 34-2 “ Ayol “ “ “ “ 1 – holotype 28A, 29A 16.01/18594 MNCN “ AYM 35-1 “ Ayol “ 1º20.3’ 8º44.0’ 44 7 – paratype 29B–C 16.01/18595 MNCN “ “ “ Ayol “ “ “ “ 1 – paratype; SEM 30A–F 16.01/18596 MNCN “ AYM 35-2 “ Ayol “ “ “ “ 5 – paratype 16.01/18597 MNCN “ AYM 36-1 “ Ayol “ 1º20.6’ 8º44.1’ 44 4 – paratype 16.01/18598 MNCN “ AYM 36-2 “ Ayol “ “ “ “ 1 – paratype; SEM 32A–D 16.01/18599 MNCN “ “ “ Ayol “ “ “ “ 5 – paratype 16.01/18600 MNCN “ AYM 37-1 “ Ayol “ 1º21.8’ 8º44.8’ 45 1 – paratype; SEM 31A–F 16.01/18601 MNCN “ “ “ Ayol “ “ “ “ 1 – paratype 29D 16.01/18602 MNCN “ “ “ Ayol “ “ “ “ 7 – paratype 16.01/18603 MNCN “ AYM 37-2 “ Ayol “ “ “ “ 7 – paratype 16.01/18604 Banc du MNCN “ BDP 55-1 “ “ 0º37.5’ 8º45.6’ 47 1 – paratype Prince 16.01/18605 …continued on the next page

Table 1. (continued)

Terebellides ramili sp. country station- sample reference campaign/oil field date longitude latitude depth specs original registration number new registration number Remarks Figures Congo 2This workN’Kossa18-11-20005º17.419’S11º34.379’E1801CEAB,129GMNCN 16.01/18613paratype “ 7““18-11-20005°16.425’S11°33.765’E2001CEAB.129DMNCN 16.01/18614paratype; SEM34A–F“9““17-11-20005°16.285’S11°33.568’E1901CEAB.AP.129FMNCN 16.01/18615 Holotype 28B, 33A–B““““17-11-2000“““2“MNCN 16.01/18616paratype Congo 75Kirkegaard (1959) Galathea 07-12-19505º41’S11º38’E2051NHMD-231438– non-type; labelled T. af. ramili 33C nov.

Terebellides sp. 2 original new station- campaign/oil country reference date longitude latitude depth specs registration registration Remarks Figures sample field number number

…continued on the next page

Table 1. (continued) South Africa Kirkegaard (Off Cape 165 Galathea 03-01-1951 n.d. n.d. 110 1 NHMD-231449 – dried out 35C–D (1959) Point)

Branchiae. Branchiae arising as single structure from SGIII, consisting of a single stalked mid-dorsal branch having one pair of dorsal (upper) lobes not fused along their length, and one pair of ventral (lower) lobes of same length, neither fused together nor to dorsal ones, arising from branchial stem. Anterior projection of dorsal lobes (lobe 5) small. Pointed projection of posterior region of both upper and lower lobes forming a short terminal papilla (Fig. 35 A−B).

Thorax. Eighteen pairs of notopodia (SGIII−XX), with those in TC1 smaller than subsequent ones. Neuropodia as sessile pinnules, from TC6 (SGVIII) to pygidium, with uncini in single rows starting from TC7 (SGIX) throughout. First neuropodia (TC 6) with eight sharply bent, acute-tipped, geniculate chaetae; second and subsequent neuropodia with up to 14−16 uncini per torus.

Abdomen. Thirty-one pairs of neuropodia as erect pinnules, with ca. 25 uncini per torus.

Other body features. A very small nephridial papilla behind first thoracic notopodia; two pairs of simple nephridial openings dorsal to each SGVI and VII (TC 4 and TC 5) notopodium. Pygidium blunt, as a funnel-like depression.

Methyl green staining pattern. Anterior CH 1 to CH 3 solid; CH 4 to CH 18 striped; more pronounced in CH 4 to CH 11; near pattern 1 of Schüller & Hutchings (2010) (Fig. 37).

Distribution and bathymetry. Congo; 200 m depth (Fig. 11D; Table 1).

Remarks. The specimen was not examined under SEM, preventing adequate observations of relevant characters (i.e., ciliation of branchial lamellae, teeth size and shape on thoracic uncini) and, thus, formal description. It is characterised by the great development of the tentacular membrane, a trait shared with T. californica and T. mediterranea which, in turn, differ from Terebellides sp. 1 in having long TC1 notopodium and notochaetae, both smaller in this specimen. Terebellides resomari Lavesque, Hutchings, Daffe, Nygren & Londoño-Mesa, 2019 also shares this character, but differs from Terebellides sp. 1 in having papillar projections over the margin of the branchial lamellae and a well-developed fifth branchial lobe.