Paradoneis armata Glémarec, 1966

Erdoğan-Dereli, Deniz & Çinar, Melih Ertan, 2019, The genus Paradoneis (Annelida: Paraonidae) from the Sea of Marmara, with descriptions of two new species, Zootaxa 4686 (4), pp. 465-496 : 466-467

Paradoneis armata Glémarec, 1966

Paradoneis armata Glémarec, 1966: 1046–1049 , Figs 1B,C ; 2 A–C; Laubier 1971: 144–146, Fig. 1 A–C; Aguirrezabalaga 2012: 248–251, Figs 110A–D, 111A–C.

Cirrophorus armatus .— Strelzov 1979: 131–133, Fig, 47A–E; Hartmann-Schröder 1996: 383–384, Fig. 180 A–C.

Material examined. 86 specimens: ESFM-POL/2013-50 , 06 June 2013, station Y2, 40°06ꞌ28ꞌꞌN, 26°22ꞌ51ꞌꞌE, 10 m , mud with shell fragments, 9 specimens; ESFM-POL /2013-56, 06 June 2013, station Y2, 40°06ꞌ32ꞌꞌN, 26°22ꞌ31ꞌꞌE, 25 m, mud with pebble, 1 specimen; ESFM-POL/2013-66 , 06 June 2013 , station Y3, 40°12ꞌ052ꞌꞌN, 26°26ꞌ350ꞌꞌE, 10 m, mud with shell fragments, 1 specimen; ESFM-POL/2013-1302 , 08 June 2013 , station Y 9, 10 m, 40°26ꞌ20ꞌꞌN, 27°11ꞌ32ꞌꞌE, mud with gravel and shell fragments, 1 specimen; ESFM-POL/2013-1298 , 07 June 2013 , station Y10, 40°31ꞌ28ꞌꞌN, 26°54ꞌ12ꞌꞌE, 10 m, sand, 38 specimens; ESFM-POL/2013-1300 , 11 June 2013 , station Y18, 40°58ꞌ01ꞌꞌN, 27°31ꞌ26ꞌꞌE, 10 m, mud with pebble, 12 specimen; ESFM-POL/2013-635 , 12 June 2013 , station Y20, 40°52ꞌ54ꞌꞌN, 27°55ꞌ38ꞌꞌE, 1000 m, 1 specimen; ESFM-POL/2013-1303 , 17 June 2013 , station Y29, 40°32ꞌ39ꞌꞌN, 28°46ꞌ42ꞌꞌE, 50 m, mudy sand, 1 specimen; ESFM-POL/2013-1304 , 14 June 2013 , station Y31, 40°01ꞌ44ꞌꞌN, 28°26ꞌ31ꞌꞌE, 10 m, sand, 5 specimens; ESFM-POL/2013-538 , 26 June 2013 , station Y50, 41°12ꞌ16ꞌꞌN, 29°07ꞌ25ꞌꞌE, 10 m, sand, 17 specimens.

Additional material examined: Paradoneis armata , Holotype, MNHN-1412 Britain; Paratypes, MNHN- 1413, 2 specimens.

Description. Largest specimen complete, 18.2 mm long, 0.54 mm wide for 151 chaetigers. Color in alcohol usu- ally light brown, yellowish. Body stout, long; anterior and middle region of similar width; body tapering to posterior part ( Fig. 2A ). Prostomium triangular; length and width equal; anterior part truncated, with an eversible palpode; without eyes. A pair of nuchal organ as deep slits, dorso-laterally placed on posterior part of prostomium ( Fig. 2B ). Peristomium located posterior to nuchal organs on dorsal side. Mouth with six buccal lips; two placed anteriorly, four placed posteriorly; posterior lips extending to anterior margin of chaetiger 2; a Y-shaped gap present between anterior lips. Branchiae numbering 15 pairs, commencing on chaetiger 4; somewhat flattened, cylindro-conically shaped, with a rounded tip; shorter than segment width ( Fig. 2B ), last two pairs much shorter than others; 218 μm long in anterior region, 305 μm long in middle region, 235 μm long in posterior region. Notopodial postchaetal lobes short, cirriform on chaetigers 1 and 2; long, cirriform between chaetigers 3 and 14; short, cirriform on posterior chaetigers. Neuropodial postchaetal lobes absent. Four types of chaetae present on chaetigers; limbate, capillary and two types of modified notochaetae (lyrate and harpoon-shaped chaetae). Limbate chaetae hirsute, present on notopodia of chaetigers 1–13 (lengths: 251–415 μm) and on neuropodia of chaetigers 1–21 (lengths: 156–300 μm). Notopodial capillary chaetae starting from chaetiger 14 to pygidium, neuropodial capillary chaetae starting from chaetiger 22 to pygidium; 104 μm long in middle region, 110 μm long in posterior region. Typical lyrate chaeta ( Fig. 2C ) starting from chaetiger 2 to chaetiger 32. Lyrate chaetae reshaping into harpoon-shaped chaetae from chaetiger 32 onwards to pygidium ( Fig. 2E ). Notopodia of anterior region bearing 1–2 typical lyrate chaeta and 22–24 lim- bate chaetae; those of middle region bearing 5–6 capillary chaetae and 1 harpoon-shaped chaeta; those of posterior region bearing 4–5 capillary chaetae and one harpoon shaped chaeta. Neuropodia of anterior region bearing 24–25 limbate chaetae; neuropodia of middle region bearing 11–12 capillary chaetae; neuropodia of posterior region bear- ing 11–12 capillary chaetae. Lyrate chaeta 53 μm long, with unequal branches; long branch 1,5–2 times longer than short branch; width of branches equal; teeth discernible on anterior chaetigers ( Fig. 2C ). Harpoon-shaped chaeta 47 μm long, with unequal branches positioning at right angle with a short arista on horizontal branch ( Fig. 2E ). Thin branch of harpoon-shaped chaeta getting thicker and thick branch of harpoon-shaped chaeta getting shorter along body. Pygidium rounded with three anal cirri; two cirri placed dorso-laterally (thin, digitiform, lengths: 74–109 μm) and one cirrus placed ventro-laterally (thick, length: 46 μm) ( Fig. 2D ).

Remarks. The Sea of Marmara’s specimens of Paradoneis armata differ from the type specimens in having a longer body size (max. 18.2 mm in the Sea of Marmara’s specimens vs. max. 8.2 mm in the type specimens), lesser branchiae (15 pairs in the Sea of Marmara’s specimens vs. 17 pairs in the type specimens). In the holotype and the specimens from the study area, the thin branch of the harpoon-shaped chaeta gets thicker along the body, while the thicker branch gets shorter along the body ( Fig. 2F, G, H ). However, the morphology of the Sea of Marmara specimens of P. armata complies well with those of holotype and paratypes, and differences do not seem important enough to consider the material as belonging to a different taxon.

Habitat and Distribution. This species was found in soft substrata at depths ranging from 10 to 1000 m in the Sea of Marmara. It was previously reported on similar habitats between 6 and 1200 m depths in the Pacific Ocean ( León-González et al. 2006), eastern Atlantic Ocean ( Aguirrezabalaga & Gil 2009) and the eastern ( Çinar et al. 2014) and western ( Laubier 1971) Mediterranean Sea. This is the first report of the species from the Sea of Marmara.

Figures

FIGURE 1. Map of the studied area with the location of sampling sites.

FIGURE 2. Paradoneis armata Glémarec, 1966. A, Complete specimen (ESFM-POL/2013-1298), stained with ShirlastainA; B, Antero-dorsal view (ESFM-POL/2013-1298), stained with Shirlastain A; C, Lyrate chaeta from chaetiger 9 (ESFM-POL/2013- 1298); D, Pygidium (ESFM-POL/2013-1298); E, Modified notochaeta from a posterior chaetiger (ESFM-POL/2013-1298); F, Modified neurochaeta of holotype from chaetiger 42; G, Modified neurochaeta of holotype from posterior chaetigers; H, Modi- fied neurochaeta of holotype from preanal chaetigers. Scale bars: A, 1304 µm; B, 500 µm; C, 26 µm; D, 92 µm; E, 18 µm; F, 22 µm; G, 32 µm; H, 31 µm.