Cirrophorus nikebianchii Langeneck, Barbieri, Maltagliati and Castelli, 2017

Erdoğan-Dereli, Deniz, Çinar, Melih Ertan & Dağli, Ertan, 2017, Cirrophorus species (Annelida: Polychaeta: Paraonidae) in the Sea of Marmara, with description of a new species, Zootaxa 4347 (1), pp. 137-150 : 138-142

Cirrophorus nikebianchii Langeneck, Barbieri, Maltagliati and Castelli, 2017

Figures 2–4

Cirrophorus nikebianchii Langeneck et al., 2017: 872 –878, fig. 1.

Cirrophorus furcatus ; Çinar et al., 2014: 747 (in part) (non Hartman, 1957)

Material examined. ESFM-POL /2013-1326, Sea of Marmara, Turkey, 13 June 2013, Y24, 41°03'55''N, 28°09'12''E, 10 m, sandy mud with shell fragments ; ESFM-POL/2012-293, 0 6 October 2012, K3, 40°08'00''N, 26°21'25''E, 0–5m, Z ostera marina Linnaeus , 5 specimens; ESFM-POL/2012-292, 26 September 2012, K2, 40°17'29''N, 26°36'56''E, 0–5 m, Zostera marina , 7 specimens; ESFM-POL/2013-1308, 6 June 2013, Y1, 40°00'27''N, 26°13'24''E, 10 m, mud, 6 specimens; ESFM-POL/2013-1309, 6 June 2013, Y2, 40°06'28''N, 26°22'51''E, 10 m, mud with shell fragments, 60 specimens; ESFM-POL/2013-1310, 6 June 2013, Y2, 40°06'32''N, 26°22'31''E, 25m, mud with pebble, 2 specimens; ESFM-POL/2013-1311, 6 June 2013, Y3, 40°12'052''N, 26°26'350''E, 10 m, mud with shell fragments, 6 specimens; ESFM-POL/2013-1312, 7 June 2013, Y4, 40°17'36''N, 26°35'51''E, 10 m, mud with shell fragments, 1 specimen; ESFM-POL/2013-1313, 7 June 2013, Y4, 40°18'09''N, 26°35'15''E, 50 m, sand, 3 specimens; ESFM-POL/2013-1314, 7 June 2013, Y10, 40°31'28''N, 26°54'12''E, 10 m, sand, 5 specimens; ESFM-POL/2013-1315, 7 June 2013, Y10, 40°30'38''N, 26°54'58''E, 25 m, maerl bed, 7 specimens; ESFM-POL/2013-1316, 10 June 2013, Y13, 40°44'59''N, 27°20'16''E, 10 m, muddy sand with shell fragments, 150 specimens; ESFM-POL/2013-1318, 10 June 2013, Y18, 40°58'01''N, 27°31'26''E, 10 m, sandy mud with Ulva sp., 1 specimen; ESFM-POL/2013-1319, 12 June 2013, Y19, 40°58'36''N, 27°42'39''E, 25 m, maerl bed, 10 specimens; ESFM-POL/2013-1320, 13 June 2013, Y24, 41°03'55''N, 28°09'12''E, 10 m, sandy mud with shell fragments, 43 specimens; ESFM-POL/2013-1322, 13 June 2013, Y24, 41°03'08''N, 28°08'44''E, 25 m, maerl bed, 1 specimen; ESFM-POL/2013-1323, 14 June 2013, Y31, 40°01'44''N, 28°26'31''E, 10 m, sand, 26 specimens; ESFM-POL/2013-1324, 14 June 2013, Y31, 40°56'40''N, 28°25'15''E, 100 m, sandy mud with shell fragments, 11 specimens; ESFM POL/2013-1325, 14 June 2013, Y31, 41°01'25''N, 28°26'23''E, 25 m, maerl bed, 5 specimens; ESFM-POL/2013-1330, 0 6 June 2013, Y2, 40°06'59''N, 26°22'04''E, 50 m, muddy sand, 2 specimens; ESFM-POL/ 2013-1331, 0 6 June 2013, Y3, 40°12'15''N, 26°26'12''E, 25 m, mud, 1 specimen; ESFM-POL/2013-1332, 0 6 June 2013, Y3, 40°13'10''N, 26°25'45''E, 50 m, sand, 2 specimens; ESFM-POL/2013-1333, 0 7 June 2013, Y4, 40°17'49''N, 26°35'44''E, 25 m, maerl bed, 4 specimens; ESFM-POL/2013-1334, 0 7 June 2013, Y4, 40°18'09''N, 26°35'15''E, 50 m, sand, 3 specimens; ESFM-POL/2013-1335, 0 7 June 2013, Y5, 40°20'55''N, 26°40'38''E, 25 m, mud, 2 specimens; ESFM-POL/2013-1336, 0 7 June 2013, Y5, 40°21'21''N, 26°39'59''E, 50 m, mud, 1 specimen; ESFM-POL/2013-1337, 0 7 June 2013, Y6, 40°26'10''N, 26°41'51''E, 10 m, mud, 5 specimens; ESFM-POL/2013- 1340, 0 8 June 2013, Y11, 40°34'50''N, 27°05'59''E, 50 m, mud, 1 specimen; ESFM-POL/2013-1341, 0 8 June 2013, Y12, 40°40'38''N, 27°16'25''E, 10 m, sand, 1 specimen; ESFM-POL/2013-1343, 0 8 June 2013, Y14, 40°24'22''N, 27°20'48''E, 25 m, mud, 2 specimens; ESFM-POL/2013-1344, 0 9 June 2013, Y16, 40°24'13''N, 27°39'47''E, 41 m, mud, 5 specimens; ESFM-POL/2013-1345, 10 June 2013, Y18, 40°54'28''N, 27°33'24''E, 25 m, maerl bed, 1 specimen; ESFM-POL/2013-1347, 17 June 2013, Y30, 40°36'37''N, 28°56'19''E, 50 m, mud, 1 specimen; ESFM- POL/2013-1349, 19 June 2013, Y40, 40°41'22''N, 29°20'58''E, 25 m, sandy mud, 6 specimens.

Description. Complete specimens 8–15 mm long, 0.24–0.42 mm wide, with 84–156 chaetigers. Colour in alcohol with different colour pattern; anterior part (i.e. first 30 chaetigers) pale yellow, posterior part dark brownish red; or whole body pale yellow with dark brownish irregular speckles or dark-brownish red. Body cylindrical; widths of prebranchial and branchial regions nearly same; in postbranchial region body gradually tapering to posterior end ( Fig. 2A ). Anterior part of prostomium rounded; prostomium longer than wide (length/width: 1.25) ( Figs. 2B–C ). Buccal lips with eight longitudinal folds extending to anterior margin of chaetiger 1 ( Fig. 2C ). Eyes absent. Peristomium fused with prostomium, not discernible on dorsal side. Antenna minute, cirriform ( Figs. 2B , 4A–B ), 8–41 µm in specimens, measuring about 1/10 of prostomial length. One pair of nuchal organs, like deep nuchal slits, dorso-laterally placed on posterior part of prostomium. Parapodia biramous. Notopodial postchaetal lobes starting from chaetiger 1, short, finger-like, increasing in length after chaetiger 3; gradually getting longer in anterior part of branchial region; becoming thin, short, cirriform in posterior part of branchial region and postbranchial region; thin, long, filiform in preanal segments ( Figs. 2A–B , 4C ). Neuropodial postchaetal lobes absent. Branchiae 39–89 pairs, beginning on chaetiger 4 (in three specimens, starting from chaetiger 3). First 17 pairs of branchiae flattened and conical with rounded tip (length/width mostly between 2–5; maximum length: 143 µm), with densely arranged cilia. Remaining branchiae short (length/width mostly between 2–4; maximum length: 107 µm), not-flattened, finger-like and mostly without cilia ( Figs. 2A–B , 4A ).

Noto- and neurochaetae on chaetiger 1 with limbate (hirsute) chaetae only. Notopodia from chaetiger 2 to chaetiger 25 with limbate, capillary and lyrate chaetae; notopodia from chaetiger 26 to end of body with capillary and lyrate chaetae only. Neuropodia from chaetiger 2 to chaetiger 26 with limbate and capillary chaetae only; neuropodia from chaetiger 26 to 41 with only capillary chaetae; neuropodia from chaetiger 41–50 to end of body with modified and capillary chaetae. In anterior part of body, notopodial limbate and capillary chaetae (almost 150 µm) always longer than neuropodial limbate (120 µm) and capillary (80 µm) chaetae; in middle part, modified neurochaetae (330 µm) usually longer than notopodial (235 µm) and neuropodial (168 µm) capillary chaetae. Modified chaetae (113 µm) on neuropodia in posterior part almost 4 times longer than capillary chaetae.

Lyrate chaetae numbering 2–4, almost 60 µm long; with unequal branches; width of branches equal, longer branch 2 times longer than smaller one; teeth discernible. The teeth of lyrate chaeta on the longer branch long, thick and more numerous whereas the smaller branch’s teeth short, thin and less abundant ( Fig. 3C ). Last 7 chaetigers devoid of lyrate chaetae in all specimens. Modified neurochaeta starting from chaetiger 39 to 50, numbering 12–13 in middle and posterior part of body; similar in shape to those typical of subgenus Strelzovia (thick, long and striped longitudinally, abruptly tapering near tip). Convex portion of chaetae with finely pilose area ( Figs. 3A–B , 4D–F ). Modified neurochaetae ( Strelzovia - type modified chaeta) in superior fascicles longer than those in inferior fascicles ( Fig. 4D )

Pygidium much wider than long, bilobated with three anal cirri; two ventro-lateral cirri (thin, digitiform) and one mid-ventral cirri (thick). Anal aperture on dorsal side ( Figs. 2D , 4C ).

Remarks. The specimens of Cirrophorus nikebianchii from the Sea of Marmara differ from the original description by having limbate chaetae, short (width of segment/length of notopodial postchaetal lobes: 2.8) notopodial postchaetal lobes in postbranchial region (distinctly longer in the original description) and bi-lobated pygidium (rounded pygidium in the original description). Unlike as stated in the original description “modified chaetae are thickened capillaries, slightly curved, with or without tapered tips, not always easy to identify”, the neuropodial modified chaeta in C. nikebianchii is not a thickened capillary, but it is an extremely long (2–4 times longer than capillary), thick, chaeta that is striped longitudinally and finely pilose on the convex side, resembling modified chaeta present in the subgenus Strelzovia . The presence of finely pilose area on the convex side was not mentioned in the original description. The other differences between the Sea of Marmara’s specimens and the original description were the number of the Strelzovia - type modified chaetae (8–21 in our specimens vs. 1–7 in the Langeneck et al. (2017) specimens); the length of the Strelzovia - type modified chaeta in posterior parapodia (almost 4 times longer than capillary chaetae in our specimens vs. 2 times shorter than capillary chaetae in the Langeneck et al. (2017) specimens); and the number of branchiae (maximally 89 in our specimens vs. maximally 72 in the Langeneck et al. (2017) specimens). These differences might be attributed to the larger size of the Sea of Marmara’s specimens (maximally 15 mm long); potential misinterpretation of some characters (neuropodial capillary chaetae) by Langeneck et al. (2017); and, possibly, poor condition of the Langeneck et al. (2017) specimens (i.e., broken modified chaetae).

Habitat. Soft substrata, Zostera marina , Posidonia oceanica , maerl bed.

Distribution. Western Mediterranean Sea, Adriatic Sea, Sea of Marmara, Aegean Sea, Levantine Sea, between 0.5 to 100 m depths.

Figures

FIGURE 2. Cirrophorus nikebianchii. A, overview (ESFM-POL / 2013 - 1326); B, anterior end, dorsal view (ESFM-POL / 2013 - 1317); C, anterior end, ventral view (ESFM-POL / 2013 - 1326); D, posterior end, lateral view (ESFM-POL / 2013 - 1326). Scale bar: A = 260 µm, B = 78 µm, C = 180 µm, D = 107 µm.

FIGURE 3. Cirrophorus nikebianchii. A, modified neurochaetae, chaetiger 124 (ESFM-POL / 2013 - 1310); B, modified neurochaeta, chaetiger 124 (ESFM-POL / 2013 - 1310); C, lyrate chaeta (ESFM-POL / 2013 - 1316). Scale bar: A = 20 µm, B = 10 µm, C = 11 µm.

FIGURE 4. Cirrophorus nikebianchii. A, overview (ESFM-POL / 2013 - 1308); B, anterior end, lateral view (ESFM-POL / 2013 - 1308); C, pygidium, ventral view (ESFM POL / 2013 - 1321); D, neuropodium, chaetiger 122 (ESFM POL / 2013 - 1310); E, lyrate chaetae, chaetiger 93 (ESFM POL / 2013 - 1310); F, modified neurochaeta, chaetiger 145 (ESFM POL / 2013 - 1311). Scale bar: A = 143 µm, B = 125 µm, C = 195 µm, D = 170 µm, E = 38 µm, F = 207 µm.