Terebellides augeneri

Parapar, Julio, Martin, Daniel & Moreira, Juan, 2020, On the diversity of Terebellides (Annelida, Trichobranchidae) in West Africa, seven new species and the redescription of T. africana Augener, 1918 stat. prom., Zootaxa 4771 (1), pp. 1-61: 13-18

publication ID

https://doi.org/10.11646/zootaxa.4771.1.1

publication LSID

lsid:zoobank.org:pub:A46FAF72-6F95-4DA3-A41D-FE770D6EDF1F

DOI

http://doi.org/10.5281/zenodo.3816167

persistent identifier

http://treatment.plazi.org/id/03BF4239-FFF9-FFD8-EAF8-C40B999FFC32

treatment provided by

Plazi

scientific name

Terebellides augeneri
status

sp. nov.

Terebellides augeneri  sp. nov.

Figures 2BView FIGURE 2, 8−10View FIGURE 8View FIGURE 9View FIGURE 10, 11AView FIGURE 11, 37View FIGURE 37; Tables 1, 2

urn:lsid:zoobank.org:act:147575A6-3605-4327-A3AD-F5F1C80A3D0D

Material examined. Type material. Six specimens: holotype ( MNCN 16.01View Materials /18579); five paratypes ( MNCN 16.01View Materials /18577, 16.01/18580, 16.01/1858 and NHMD-636919, Table 1)  .

Diagnosis. Small/medium-sized species (7–19 mm in length). Branchial anterior lobe absent; posterior ventral lobes thinner than dorsal ones, with terminal projections, directly emerging from branchial stem. TC1 notopodia and notochaetae as long as following. Thoracic neurochaetae with rostrum / capitium length about 1/1, and capitium with a first row of 5–6 medium sized teeth followed by progressively smaller teeth.

Description based on holotype

Measurements and general body features. Complete specimen, 19 mm long and 1.5 mm wide; female with oocytes in body cavity ( Fig. 2BView FIGURE 2). Body tapering posteriorly with segments increasingly shorter and crowded towards pygidium. Prostomium compact; large tentacular membrane surrounding mouth, with typical buccal tentacles and expanded tips ( Fig. 8CView FIGURE 8, 9AView FIGURE 9). SGI as an expanded structure below tentacular membrane. Lateral lappets on SGIII– VII (TC1–5), larger in SGIV–VI (TC2–4) ( Fig. 2BView FIGURE 2, 8View FIGURE 8 C–D, 9A).

Branchiae. Branchiae arising as single structure from SGIII, with a single stalked mid-dorsal branch, one pair of dorsal (upper) not-fused lobes, and a pair of shorter ventral (lower) lobes, neither fused to each other, nor to dorsal ones, with short terminal projections ( Fig. 9CView FIGURE 9). Anterior projection of dorsal lobes (lobe 5) absent ( Fig. 2BView FIGURE 2). Both sides of branchial lamellae having several parallel rows of cilia and low ciliated tufts on lamellar outer edge ( Fig. 9View FIGURE 9 B−C).

Thorax. Eighteen pairs of notopodia (SGIII−XX), those of TC1 about as long as following ones. All notochae- tae as simple capillaries. Neuropodia as sessile pinnules from TC6 (SGVIII) to body end, with uncini in single rows, from TC7 (SGIX) throughout. First neuropodia on TC6, with 4–5 sharply bent, acute tipped, geniculate chaetae with minute teeth forming a well-defined capitium ( Fig. 10View FIGURE 10 C−D). From TC7, neuropodia with up to 5–10 uncini per torus in one row, with long shafted denticulate hooks, rostrum about same length as capitium, with 5−6 medium-sized teeth above main fang, and surmounted by two rows of progressively shorter teeth ( Fig. 10View FIGURE 10 A−B).

Abdomen. Thirty-one pairs of neuropodia, as erect pinnules with about 20−25 uncini per torus, with four teeth above main fang surmounted by an upper crest of similar sized teeth ( Fig. 10View FIGURE 10 E−F) and several smaller teeth above.

Other body features. Nephridial (?) papilla behind TC1; nephridial openings dorsal to any anterior thoracic notopodium not seen. Pygidium blunt, as a funnel-like depression.

Methyl green staining pattern. Anterior CH 1 to CH 4 solid; CH 5 to CH 11 striped; near pattern 1 of Schüller & Hutchings (2010) ( Fig. 37View FIGURE 37).

Variability. Body ranging from 7.0 to 19.0 mm in length.

Type locality. Off Angola; 73 m depth (Table 1)  .

Distribution and bathymetry. Off Angola; 72−83 m depth ( Fig. 11AView FIGURE 11; Table 1).

Etymology. This species is named after the German scientist and prolific marine zoologist Hermann Augener (1872–1938), as an homage to his numerous contributions to polychaete taxonomy.

Remarks. The branchiae of T. augeneri  sp. nov. resemble those of T. hutchingsae Parapar, Moreira & Martin, 2016  in bearing ventral lobes much less developed than the dorsal ones and arising from the base of the latter, but differ in having wider and longer lobes and in lacking a longer terminal projection. Both species also differ in the size of the ciliature in branchial lamellae outer edge (much lower in T. augeneri  sp. nov.), in the shape of thoracic uncini (with teeth surmounting the rostrum much bigger in T. augeneri  sp. nov.) and in bearing geniculate chaetae in CH 5 and CH 6 (only in CH 6 in T. augeneri  sp. nov.).

Terebellides ceneresi Lavesque, Hutchings, Daffe, Nygren & Londoño-Mesa, 2019  has in common with T. augeneri  sp. nov. the general branchial shape, with very similar branchial lobes and ciliary tufts on both sides of the outer edge of lamellae and no papillar projections pointing over their edge. Nevertheless, both species differ in the thoracic uncini, both in the shape of main fang (straight in T. augeneri  sp. nov.; terminally bent in T. ceneresi  ) and the denticulation of capitium (5–6 teeth in first row in T. augeneri  sp. nov.; 3–4 in T. ceneresi  ).

Terebellides shetlandica Parapar, Moreira & O’Reilly, 2016  also bears ventral branchial lobes not fused to dorsal ones and arising directly from the branchial stem. However, it is much smaller than T. augeneri  sp. nov. (up to 15 mm; Parapar et al., 2016c), the four posterior lobes are of similar size, and the branchial lamellae do not bear ciliated papillae.

In African Atlantic waters T. augeneri  sp. nov. most closely resembles T. ramili  sp. nov. (see below). However, it inhabits much deeper bottoms and is unique among African species because in the thoracic uncini all teeth surmounting the rostrum are very small and of the same size; in all other species, the first-row teeth are always larger than those of posterior rows.