Myxicola sulcata Ehlers, 1912

Tovar-Hernández, María Ana, León-González, Jesús Ángel De & Bybee, David R., 2017, Sabellid worms from the Patagonian Shelf and Humboldt Current System (Annelida, Sabellidae): Phyllis Knight-Jones’ and José María Orensanz’s collections, Zootaxa 4283 (1), pp. 1-64: 17-21

publication ID

10.5281/zenodo.828032

publication LSID

lsid:zoobank.org:pub:E62F2AD9-112F-40F0-B8E4-6FF79D27C8B2

persistent identifier

http://treatment.plazi.org/id/EE3E87C6-FFBB-A358-FF7F-DD29FBA85C75

treatment provided by

Plazi

scientific name

Myxicola sulcata Ehlers, 1912
status

 

Myxicola sulcata Ehlers, 1912  , redescription

( Figs 6–8View FIGURE 6View FIGURE 7View FIGURE 8, 32View FIGURE 32 A)

Myxicola sulcata Ehlers, 1912: 29  –30, pl. 3, figs 5–12.— Hartman 1966: 122, pl. 40, figs 4–7 (redrawn from Ehlers 1912).— Tovar-Hernández 2010: 17.

Material examined. ARGENTINA, UANLAbout UANL 8046View Materials: Puerto Ingeniero White , Bahía Blanca, 38°46′S, 62°16′W, 28 October 1968, intertidal, on dock pilings, coll. S. Valentinuzzi, 5 specimensGoogleMaps  . Campana SAOAbout SAO I: UANLAbout UANL 8047View Materials: Golfo de San Matías , St. 9a, 41°01’30”S, 64°11’W, 18 m depth, sedimentary rock, 14 February 1971, coll. J.M. Orensanz, 1 specimenGoogleMaps  ; UANL 8048: St. 53, 41°00’S, 65°06’W, 38 m depth, gravel & shell, 17 February 1971, coll. J.M. Orensanz, 1 specimen. Campaña SAO II, UANLAbout UANL 8049View Materials: Golfo de San Matías , St. 103, 40°59’S, 64°23’W, 64 m depthGoogleMaps  , 4 May 1971, 1 fragment undergoing hystolisis. Campaña SAO V, UANLAbout UANL 8050View Materials: Golfo de San Matías, St. 230, off Bajo Oliveira , 18.2 m depth, sand, 5 March 1973, coll. J.M. Orensanz, 1 specimen  . Campaña, 1, UANLAbout UANL 8051View Materials: Golfo de San José, off El Riacho , subtidal, 42°24’S, 64°35’W, May 1976, coll. J.M. Orensanz, 2 specimens, one female with oocytes in abdomenGoogleMaps  ; UANLAbout UANL 8052View Materials: Golfo de San José, dredge haul 5, E of Tehuelche , 3 miles offshore, 42°22’S, 64°16’W, 47,5 m depth, coll. J.M. Orensanz, 11 May 1976, 1 specimenGoogleMaps  . Campaña Goyena II, UANLAbout UANL 8053View Materials: Mar del Plata , St. 12, 38°03.9’S, 57°22’W, coarse sand, shell, 12 specimensGoogleMaps  ; UANLAbout UANL 8054View Materials: Bahía San Blas, 40°33’S, 62°14’W, February 1982, intertidal, coll. A. Moguilevsky, 1 specimen complete but with histolysis in branchial crownGoogleMaps  . URUGUAY, Campaña Akademik Knipovich, UANL 8055: St. 250, 34°51’S, 52°35’W, 83 m depth, 1965, 1 specimen. Campaña Atlantis II, UANL 8056: St. 284, 36°08.3’S, 53°42.3’W, 98 m depth, 1971, 1 specimen.

Redescription. Trunk length 9–35 mm, width 2.5– 4 mm, cylindrical in cross section ( Fig. 7View FIGURE 7 D). Branchial crown length 6–12 mm, with semicircular radiolar lobes fused dorsally, bearing 12–17 pairs of radioles ( Fig. 7View FIGURE 7 C). Eight thoracic and 35–72 abdominal segments. Dorsal and ventral basal flanges absent. Palmate membrane between radioles along 3/4 of their length; radioles with broad radiolar flanges, and long, filiform bare tips ( Fig. 6View FIGURE 6 I); radioles with longest pinnules distally ( Figs 6View FIGURE 6 I, 7F). Dorsal lips small, with radiolar appendages located in inner margin of each dorsal lip ( Fig. 8View FIGURE 8 B, C), adjacent to mouth. Ventral lips well developed, broadly rounded, extending from dorsal-most edges of inner branchial lobe margins to ventral-most edges ( Figs 8View FIGURE 8 A–C); dorsal pinnular appendages absent and ventral radiolar appendages all absent. Parallel lamellae and ventral sacs absent. Posterior peristomial ring collar absent ( Figs 6View FIGURE 6 A, B, D, E; 7A, B). Anterior peristomial ring with triangular ventral lobe, distally entire ( Fig. 6View FIGURE 6 B); laterally with shallow notch ( Fig. 6View FIGURE 6 D, E). Narrow glandular ridge on chaetiger 2 ( Fig. 7View FIGURE 7 A, B). Ventral shields absent throughout. Interramal eyespots absent but perhaps they fade. First notopodia with thin elongate-narrowly hooded chaetae. Following thoracic chaetigers with almost inconspicuous notopodia, with 10–20 thin, elongate narrowly-hooded chaetae arranged in transverse rows anterior to uncini ( Fig. 7View FIGURE 7 G). Thoracic neuropodia with acicular uncini with curved tips as hooks, each equipped with narrow tooth above main fang (unidentate), hood absent ( Fig. 7View FIGURE 7 G–I), handle broad medially, then thickened to basal end. Companion chaetae absent. Abdominal neurochaetae narrowly-hooded, on almost inconspicuous neuropodia. Abdominal notopodial tori forming almost complete cinctures around body, except for faecal groove ( Fig. 6View FIGURE 6 G, H), with avicular uncini with one row of two teeth above main fang, breast well developed and handle minute ( Fig. 7View FIGURE 7 J). Pygidium triangular ( Fig. 6View FIGURE 6 C, F), pygidial cirrus absent. Tubes not preserved.

Type locality. Antarctic, Ross Sea, Winter Quarters.

Remarks. Rullier & Amoreux (1979) reported Myxicola aesthetica  , a species described from Italy, near Cabo Polonio ( Uruguay), 25 m depth, but in that contribution neither figures nor description were provided.

Orrhage (1980) and Fitzhugh (1989) reported the genus Myxicola  as lacking ventral lips but in later studies this was modified. Fitzhugh (2003) and Capa et al. (2011) corroborated the presence of ventral lips extending dorsoventrally along the entire interior margin of the branchial lobes (wrap around dorsal lips), as opposed to only adjacent to the ventral half of radioles, as in all other sabellid genera.

When branchial lobes were opened dorsally using forceps to describe dorsal lips morphology in M. sulcata  , a pair of broadly rounded lips were visible ( Fig. 8View FIGURE 8 A, also see Giangrande et al. 2012: fig. 11F for M. infundibulum  ). Each lip presented a finger-like radiolar appendage on its inner margin, which is surrounded partially by the ventral lip ( Fig. 8View FIGURE 8 B, C). This appendage would represent the dorsal lip. According to Fitzhugh (2003) and Capa et al. (2011), these enveloping lips are ventral, instead of the dorsal lips. The digitiform processes of dorsal lips were interpreted by Fitzhugh (2003) as a combination of dorsal lips and radiolar appendages, and the overall structures that essentially surround the dorsal lips were therefore considered as the ventral lips.

UANL

Universidad Autonoma de Nuevo Leon

SAO

Sammlung Oberli

Kingdom

Animalia

Phylum

Annelida

Class

Polychaeta

Order

Sabellida

Family

Sabellidae

Genus

Myxicola

Loc

Myxicola sulcata Ehlers, 1912

Tovar-Hernández, María Ana, León-González, Jesús Ángel De & Bybee, David R. 2017

2017
Loc

Myxicola sulcata

Hartman 1966: 122Ehlers 1912: 29

1966