The diversity of the genus Aricidea (Polychaeta: Paraonidae) from the Sea of Marmara, with descriptions of two new species and two new records for the Mediterranean fauna Author Erdoğan-Dereli, Deniz 0000-0003-2754-8378 dnzer09@gmail.com Author Çinar, Melih Ertan text Zootaxa 2020 2020-08-31 4844 1 1 73 journal article 8538 10.11646/zootaxa.4844.1.1 4734c0c4-4948-4b10-beb1-ad949fbd7673 1175-5326 4405867 770E285A-3CB3-4649-B70F-631D5AB91EC7 Aricidea ( Acmira ) simonae Laubier & Ramos, 1974 ( Figures 13–16 ) Aricidea simonae Laubier & Ramos 1974: 1123–1127 , figs. 9–10. Aricidea ( Acmira ) simonae : Aguirrezabalaga & Gil 2009: 662–664 , fig. 21 B–C; Kurt-Şahin et al. 2019: 161–163 , fig. 8. Material examined. ESFM-POL/2012-495 , 01 October 2012 , station K15, 40°41’38’’N , 29°36’26’’E , 0,5 m , Mytilus galloprovincialis , 1 specimen ; ESFM-POL/2013-1141 , 08 June 2012 , station Y15, 40°25’41’’N , 27°27’57’’E , 50 m , fine sand, 1 specimen ; ESFM-POL/2013-1142 , 09 June 2013 , station Y17, 40°39’58’’N , 27°41’08’’E , 50 m , mud, 4 specimens ; ESFM-POL/2013-1145 , 11 June 2013 , station Y18, 40°54’28’’N , 27°33’24’’E , 100 m , sand with mud shell fragments, 2 specimens ; ESFM-POL/2013-1146 , 12 June 2013 , station Y19, 40°58’36’’N , 27°42’39’’E , 25 m , maerl bed, 1 specimen ; ESFM-POL/2013-1147 , 13 June 2013 , station Y24, 41°03’55’’N , 28°09’12’’E , 10 m , sandy mud with shell fragments, 1 specimen ; ESFM-POL/2013-1148 , 16 June 2013 , station Y24, 41°00’16’’N , 28°07’50’’E , 50 m , sand with mudy shell fragments, 4 specimens ; ESFM-POL/2013-590 , 23 June 2013 , station Y32, 40°55’06’’N , 28°34’11’’E , 100 m , sandy mud, 1 specimen . Description . Largest specimen incomplete, 26.5 mm long, 1.33 mm wide, with 85 chaetigers. Color in alcohol usually white, with brown speckles on body. Body stout; straight, anterior part and posterior part of body nearly same thickness ( Fig. 13A ). Prostomium subtriangular, much wider than long (ratio length / width: 0.81); anterior margin rounded, with eversible palpode; eyes absent ( Figs. 13B ; 14 A–C). Crown-like ciliary band (clcb) present ( Figs 14 B–C). M-shaped transversal ciliary band (cb) present, thin, placed just anterior to antenna and contacting nuchal organs ( Fig. 14C ). Antenna short, thin, reaching the end of prostomium; inflated on tip (antenna length / prostomium length: 0.35); with a central insertion ( Figs 13E ; 14 A–C). A pair of nuchal organs long, wide and slightly curved slits placed laterally in posterior part of prostomium; more or less concave shape; extending almost 3/5 of prostomium; without coloration ( Figs 13E ; 14C ). Mouth with three buccal lips; two placed anteriorly, one placed posteriorly and extending to anterior margin of chaetiger 2, with five longitudinal folds. A dorsal ciliary band (dcb) present on mid-dorsal transversal line of each prebranchial and branchial chaetigers ( Fig. 14C ). Short dorsal ciliary bands (sdcb) absent. Ciliary bands absent on ventral side of body. Branchiae 20–24 pairs, starting on chaetiger 3; thin, cylindro-conical shaped and somewhat flattened, with a rounded tip; shape similar along branchial region; 710 μm long in anterior region, 860 μm in middle region and 645 μm in posterior region; ciliary bands on both sides of branchiae ( Figs 13 A–B; 15A, C). Interramal lobes present in branchial region, located between noto- and neuropodia as a distinct large ridge ( Figs 13 B–C, F; 15A, C; 16B). Notopodial papilla absent ( Fig. 15A, C ). Notopodial postchaetal lobes long, thin and filiform on first two chaetigers; long and digitiform in branchial region; and becoming shorter in posterior region ( Figs 13C, F ; 15 A–C). Neuropodial postchaetal lobes absent. Ventral lobes present, from chaetiger 1 to chaetiger 14 ( Figs 13F ; 15A, C ). Lateral sense organs present, from chaetiger 1 to end of branchial chaetigers; located between notopodia and neuropodia, just posterior to notopodial postchaetal lobes; each sense organ in a straight line with regularly clustered pores; with 25–27 pores in prebranchial region (long axis of organ: 7–8 μm), and about 50–52 pores (long axis: 16–17 μm) in branchial region; with flexible cilia distinctly protruding from opening or embedded into pores ( Fig. 16 A–D). Two main types of chaetae present in chaetigers; capillary and modified neurochaetae ( Figs 13D, F ; 15 B–D; 16B). Capillary chaetae arranged in bundles, present on both neuropodia and notopodia of all chaetigers ( Figs 15 B–D; 16B); approximately 355 μm long in anterior region, 494 μm long in middle region, 655 μm long in posterior region. Anterior notopodia with 22–34 capillary chaetae; middle notopodia with 28–37 capillary chaetae; posterior notopodia with 10–14 capillary chaetae. Anterior neuropodia with 28–37 capillary chaetae; middle neuropodia with 35–41 capillary chaetae; posterior neuropodia with 9–12 capillary chaetae. Modified neuropodial chaetae robust, long, with a slightly curved subterminal region ( Fig. 13D ); present from chaetiger 57 to posterior end, numbering 12–15; superior chaetae longer (about 115 μm). Pygidium missing. Remarks. The specimens of Aricidea simonae from the Sea of Marmara had interramal lobes between the noto- and neuropodia. These were not been mentioned in the original and subsequent descriptions of this species ( Laubier & Ramos 1974 ; Hartmann-Schröder 1996 ; Aguirrezabalaga 2012 ; Kurt-Şahin et al . 2019 ). Although not described, Laubier & Ramos (1974) illustrated this character in the cross-section of a chaetiger from the branchial region (see Figure 10B ). FIGURE 13 . Aricidea ( Acmira ) simonae . A, General view of dorso-lateral side of anterior end (ESFM-POL/2013-1145); B, Dorso-lateral view of anterior end (ESFM-POL/2013-1145); C, Lateral view of chaetiger 7, stained with Shirlastain-A (ESFM-POL/2013-1148); D, Modified neurochaetae with capillary chaetae of chaetiger 62 (ESFM-POL/2013-1148); E, Dorsal view of prostomium (ESFM-POL/2013-1145); F, Cross section of chaetiger 8 (ESFM-POL/2013-1148). Abbreviations: irl, interramal lobe; ntpcl, notopodial postchaeetal lobe; vl: ventral lobe. Scale bar: A, 1166 µm; B, 500 µm; C, 101 µm; D, 30 µm; E, 130 µm; F, 210 µm. FIGURE 14 . Aricidea ( Acmira ) simonae (ESFM-POL/2013-1142). A, Dorsal view of anterior end; B, Lateral view of anterior end; C, Dorsal view of prostomium with first two chaetigers. Abbreviations: clcb, crown-like ciliary band; cb, ciliary band; dcb, dorsal ciliary band; ep, eversible palpode; irl, interramal lobe; no, nuchal organ. Scale bar: A, 625 µm; B, 341 µm; C, 388 µm. FIGURE 15 . Aricidea ( Acmira ) simonae (ESFM-POL/2013-1142). A, Dorso-lateral view of anterior end; B, Notopodia of mid-branchial chaetigers; C, Lateral view of mid-branchial chaetigers; D, Parapodia of posterior chaetigers. Abbreviations: irl, interramal lobe; ntpcl, notopodial postchaeetal lobe; vl, ventral lobe. Scale bar: A, 590 µm; B, 76 µm; C, 161 µm; D, 104 µm. FIGURE 16 . Aricidea ( Acmira ) simonae (ESFM-POL/2013-1142). A, Lateral sense organ of chaetiger 1; B, Notopodium and neuropodium of chaetiger 8; C, Lateral sense organ of chaetiger 8; D, Detail from figure C, lateral sense organ. Abbreviations: bran, branchia; irl, interramal lobe; lso, lateral sense organ; ntpcl, notopodial postchaeetal lobe. Scale bar: A, 17 µm; B, 107 µm; C, 16 µm; D, 6 µm. In contrast to other Aricidea species found in the study area, which have more or less convex-shaped nuchal organs, Aricidea simonae has long concave-shaped nuchal organs (see Figs. 3C ; 6D ; 11C ; 20B ; 26F ; 31B ; 34C ; 40B ; 44C ; 48A ). This type of nuchal organ was previously illustrated on the prostomium of A. simplex Day, 1963 ( Day 1963 ; Strelzov 1979 ; Blake 1996 ), A. longicornuta Berkeley & Berkeley, 1950 ( Berkeley & Berkeley 1950 ), A. mirifica Strelzov, 1973 and A. pulchra Strelzov, 1973 ( Strelzov 1979 ) , and A. neosuecica nipponica Imajima, 1973 ( Imajima 1973 ) . Among the other species found in the present study, the M-shaped ciliary band on the prostomium is unique for A. simonae and A. cerrutii . However, unlike A. cerrutii , this ciliary band is associated with the nuchal organs in A. simonae . Habitat and Distribution. Aricidea simonea was found in soft substrata and Mytilus galloprovincialis biotope at depths ranging from 0.5 m to 100 m in the Sea of Marmara. The species was previously reported on similar habitats between 2 and 1113 m depths in the north-east Atlantic Ocean (Gil & Sard 1999; Aguirrezabalaga & Gil 2009 ), eastern ( Çinar et al. 2014 ) and western Mediterranean Seas ( Laubier & Ramos 1974 ; Katzmann & Laubier 1975 ), and the Black Sea ( Kurt-Sahin et al. 2019 ).