Kirkegaardia papaveroi, Freitas & Ribeiro & Ruta, 2022

Freitas, Roberta, Ribeiro, Rannyele Passos & Ruta, Christine, 2022, Kirkegaardia Blake, 2016 (Annelida: Cirratulidae) from Southeastern Brazil with description of nine new species, PLoS ONE (e 0265336) 2016 (5), pp. 1-27 : 19-20

Kirkegaardia papaveroi sp. nov.

urn:lsid:zoobank.org:act:A21CC609-BAFF-4B0E-AC2F-9A2B5C2F2101 .

Fig 10

Material examined. BRAZIL: Campos Basin – Holotype – -19.78693056˚S -39.92095000˚W, 14 m, 16/07/2011, one ind., ( MNRJP-003008 );– Paratypes – -19.79245278˚S -39.72085556˚W, 34 m, 15/08/2010, one ind., ( MNRJP-003009 ); -19.87652222˚S -39.81823056˚W, 42 m, 16/12/ 2010, one ind., ( MNRJP-003010 ); -19.70894722˚S -39.64926667˚W, 35 m, 14/12/2010, one ind., ( MNRJP-003011 ); -19.92907222˚S -39.76075000˚W, 46 m, 16/12/2010, one ind., ( MNRJP-003012 ); -19.74557222˚S -39.77555833˚W, 29 m, 15/07/2011, two ind., ( MNRJP-003013 ); -19.87490556˚S -39.81891667˚W, 41 m, 16/07/2011, one ind., ( MNRJP-003014 ); -19.69027500˚S -39.52233889˚W, 44 m, 13/07/2011, 15 ind., ( MNRJP-003015 ); -19.60143611˚S -39.17581389˚W, 145 m, 21/04/2012, one ind., ( MNRJP-003016 ).

Diagnosis. Peristomium elongated, with two lateral grooves producing rings. Peristomial dorsal crest present. Neurosetae with denticles; with serrated edge of fibrils along shaft from about 20 abdominal setigers. Pre-pygidial region expanded.

Description. Holotype with 63 setigers, 2.4 mm long, thoracic region 0.09 mm wide, 0.1 mm high, abdominal region 0.06 mm wide. Prostomium short, triangular, bluntly rounded on anterior margin ( Fig 10A ). Eyes absent. Peristomium elongated, with one lateral groove producing two rings, peristomial dorsal crest present ( Fig 10A ). Dorsal tentacles on posterior margin of peristomium. First pair of branchiae posterolateral to dorsal tentacles at boundary with setiger 1 ( Fig 10A ), branchiae rarely present in abdominal segments. Thoracic setigers about as wide as long for first nine or ten setigers, with parapodia shifted dorsally and elevated above mid-dorsal surface, forming distinct mid-dorsal groove on thoracic segments ( Fig 11A ), thoracic crest present ( Figs 10A and 11A ). Abdominal segments becoming longer and narrower and with parapodia located laterally ( Fig 11B ). Thoracic parapodia with smooth capillaries numbering about 4–6 in notopodia and neuropodia. Anterior abdominal segments with smooth capillaries in noto- and neuropodia gradually replaced by denticulate capillaries, fascicles reduced to 3–5 setae in abdominal setigers. Noto- and neurosetae heavily serrated or denticulated ( Fig 10B and 10C ). Neurosetae with denticles and serrated edge of fibrils along shaft from about 20 abdominal setigers ( Fig 10C ). Pre-pygidial region expanded with dorsal groove ( Fig 10D ). Pygidium formed by a simple ventral lobe ( Fig 10D ).

Remarks. The presence of a peristomial crest brings Kirkegaardia papaveroi sp. nov. as well as Kirkegaardia jongo sp. nov., and Kirkegaardia goytaca sp. nov. into the group of species termed Kirkegaardia dorsobranchialis-heterochaeta by Blake [ 27] which includes the species: K. annulosa , K. cristata K. kladara and K. hampsoni . K. annulosa differs from K. papaveroi sp. nov. by having unusual spike like serrated neurosetae in addition to denticulated capillaries. Among these species, K. hampsoni and K. jongo sp. nov. differs from K. papaveroi sp. nov. by lacking the thoracic dorsal crest. Kirkegaardia papaveroi sp. nov. it differs from K. cristata in that it does not have a prominent ventral sulcus in the first abdominal setigers, in that it has 0–2 distinct rings in the peristomium instead of three. Kirkegaardia papaveroi sp. nov. differs from K. kladara by the branchiae arising lateral to the dorsal tentacles on the peristomium instead of setiger 1. K. goytaca sp. nov. differs from K. papaveroi sp. nov. by having the thoracic region extremely narrow. For all these differences, K. papaveroi was considered as new to science.

Etymology. This species is named in honor of Dr. Nelson Papavero for his important contribution to zoology in Brazil.

Figures

Fig 10. Kirkegaardia papaveroi sp. nov. (A) Anterior end, lateral view; (B) notopodial capillary denticulated; (C) neuropodial capillary denticulated; (D) posterior end, dorsal view. https://doi.org/10.1371/journal.pone.0265336.g010

Fig 11. Kirkegaardia papaveroi sp. nov. (A) Anterior end, lateral view; (B) abdominal segments, dorsal view. A and B (MNRJP-003008). Type locality. Atlantic Ocean: Campos Basin (Brazil).Habitat. Sandy sediments, 14 and 145 m depth. Distribution. Presently known only from Atlantic Ocean: Campos Basin (Brazil). Methyl Green. No pattern, stain not retained. https://doi.org/10.1371/journal.pone.0265336.g011