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

http://doi.org/ 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 6–8 View FIGURE 6 View FIGURE 7 View FIGURE 8 , 32 View 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, UANL 8046 View Materials : Puerto Ingeniero White , Bahía Blanca, 38°46′S, 62°16′W, 28 October 1968, intertidal, on dock pilings, coll. S. Valentinuzzi, 5 specimens GoogleMaps   . Campana SAO I: UANL 8047 View 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 specimen GoogleMaps   ; 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, UANL 8049 View Materials : Golfo de San Matías , St. 103, 40°59’S, 64°23’W, 64 m depth GoogleMaps   , 4 May 1971, 1 fragment undergoing hystolisis. Campaña SAO V, UANL 8050 View 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, UANL 8051 View 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 abdomen GoogleMaps   ; UANL 8052 View 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 specimen GoogleMaps   . Campaña Goyena II, UANL 8053 View Materials : Mar del Plata , St. 12, 38°03.9’S, 57°22’W, coarse sand, shell, 12 specimens GoogleMaps   ; UANL 8054 View Materials : Bahía San Blas, 40°33’S, 62°14’W, February 1982, intertidal, coll. A. Moguilevsky, 1 specimen complete but with histolysis in branchial crown GoogleMaps   . 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. 7 View FIGURE 7 D). Branchial crown length 6–12 mm, with semicircular radiolar lobes fused dorsally, bearing 12–17 pairs of radioles ( Fig. 7 View 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. 6 View FIGURE 6 I); radioles with longest pinnules distally ( Figs 6 View FIGURE 6 I, 7F). Dorsal lips small, with radiolar appendages located in inner margin of each dorsal lip ( Fig. 8 View 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 8 View 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 6 View FIGURE 6 A, B, D, E; 7A, B). Anterior peristomial ring with triangular ventral lobe, distally entire ( Fig. 6 View FIGURE 6 B); laterally with shallow notch ( Fig. 6 View FIGURE 6 D, E). Narrow glandular ridge on chaetiger 2 ( Fig. 7 View 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. 7 View 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. 7 View 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. 6 View FIGURE 6 G, H), with avicular uncini with one row of two teeth above main fang, breast well developed and handle minute ( Fig. 7 View FIGURE 7 J). Pygidium triangular ( Fig. 6 View 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. 8 View 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. 8 View 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: 122
Ehlers 1912: 29
1912