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

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 : 24-27

Notaulax salazari sp. nov.

( Figs 11 , 12 , 32 B)

Material examined. Type material: ARGENTINA, Holotype ( UANL 8060 ), two paratypes ( UANL 8061 ), Puerto Deseado , Provincia de Santa Cruz, fouling, 0 m depth at low tide, 18 October 2005, coll. E. Schwindt. Additional material: ARGENTINA, Campaña R / V Walther Herwig 15, UANL 8062 : St. 383, 40°22’S, 59°02’W, 90 m depth, 19 July 1966, 1 specimen .

Description. Trunk length 29 mm (18 – 29 mm), width 1.5 mm (1.2 – 1.5 mm). Branchial crown length 11 mm (8 mm), with 14 pairs of radioles. Eight thoracic and 58 abdominal segments (28 – 44, but types lack posterior ends). Branchial lobes joined mid-dorsally. Basal lamina longer than collar segment ( Fig. 11 B). Bases of branchial crown with flanges: dorsal ones prominent ( Fig. 11 A, B, D, E), ventral flanges reduced. Radioles arranged in two semicircles (13–14 pairs), not involute mid-ventrally and joined by palmate membrane extending 1/3 branchial crown length. Outer margins of radioles flat with broad flanges extending to radiolar tips. Radiolar tips of dorsal and lateral radioles long, occupying space of 10 pinnules ( Fig. 12 B), most ventral radioles with short tips (space of 4 pinnules, Fig. 12 C). Two rows of lensed eyes per radiole located at 3/4 branchial crown length, separate from palmate membrane, each row with 7–8 eyes ( Fig. 12 A). Dorsal lips long, one-half branchial crown length, triangular with radiolar appendage. Ventral lips short, rounded lobes. Radiolar appendages fused to dorsal or ventral lips absent. Parallel lamellae and ventral sacs present, between branchial lobes. Dorsal margins of collar Vshaped, fused to faecal groove ( Fig. 11 A, D). Lateral collar margins oblique; anterior peristomial ring not exposed ( Fig. 11 B, C, E). Ventral collar lappets triangular, distal margins rounded, with medium incision, 1/2 ventral length of collar ( Fig. 11 C, F). Ventral shield of chaetiger 1 rectangular, entire and one- half as wide as adjacent shields ( Fig. 11 C, F). Subsequent ventral shields entire, trapezoidal, laterally indented by neuropodial tori ( Fig. 11 C, F). Chaetiger 1 with long, slightly oblique longitudinal rows of more than 45 spine-like chaetae. Chaetigers 2 – 8 with notopodia and neuropodia. Superior notochaetae spine-like ( Fig. 12 D); inferior notochaetae paleate, without mucro ( Fig. 12 D, E). Thoracic uncini avicular, with medium-size handles, developed breast and several rows of minute, similar-size teeth above main fang; companion chaetae with rounded denticulate heads and long, gently tapering asymmetrical membranes. Abdominal interamal eyespots absent. Abdominal tori located anterior to intersegmental lines. Avicular abdominal uncini similar to thoracic; five abdominal paleate neurochaetae with long mucros, and five needle-like chaetae posterior to paleae, two times longer than paleae ( Fig. 12 F). Pygidial eyespots unknown. Tubes unknown.

Type locality. Puerto Deseado , Provincia de Santa Cruz, fouling, 0 m depth at low tide.

Etymology. The species is named after Dr. Sergio I. Salazar-Vallejo, in recognition for his vast knowledge and research on polychaetes. His many publications on polychaetes, importance of taxonomy, his dedication to his students, criticism, simplicity and remarkable generosity are part of his legacy. He also made possible the shipment of additional sabellid samples from Argentina to Mexico.

Remarks. As stated above, only one species of Notaulax has been described from South America, N. tilosaula , from the Chilean coast, and there are some records for N. phaeotaenia ( Schmarda, 1861) in southern waters (see remarks on N. tilosaula ), as well as N. occidentalis ( Baird, 1865) by Nonato & Luna (1970) and Rullier & Amoureux (1979), as Hypsicomus elegans ( Webster, 1884) and Costa-Paiva & Paiva (2007).

Notaulax salazari sp. nov., differs from N. phaeotaenia and N. tilosaula in several features: the ventral margins of collar are entire in N. phaeotaenia and incised in N. tilosaula , for about 1/4 the length of ventral lappets, while in N. salazari sp. nov., there is an incision about 1/2 the length of ventral lappets. In N. salazari sp. nov. dorsal collar margins are V-shaped (oblique in N. tilosaula and N. phaeotaenia ) and angle of lateral collar margins diagonal (V-shaped in N. tilosaula and even in N. phaeotaenia ). The ventral shield of the collar is entire in N. salazari sp. nov., and divided in two areas in N. tilosaula and N. phaeotaenia .

Notaulax occidentalis have a single row of 10–30 radiolar eyes beginning just above the palmate membrane and extending for up to slightly more than 1/2 the free length of radioles ( Perkins 1984; Tovar-Hernández & Salazar-Vallejo 2006). Notaulax salazari sp. nov., presents two rows of lensed eyes per radiole, located at 3/4 of the branchial crown length, separated from the palmate membrane, each row with only 7–8 eyes. Notaulax tilosaula has two rows of 30–38 lensed eyes located above palmate membrane and extending to 1/2 of the branchial crown length, the radiolar tips are twice as long as those in N. tilosaula , and interramal eyespots are present in N. tilosaula and absent in N. salazari sp. nov.

Notaulax midoculi ( Hoagland, 1919) , a species described from Florida, also has a lower number of radiolar eyes, as in N. salazari sp. nov., (6 versus 7–8 in N. salazari ). However, these species differ in the shape of ventral lappets of the collar, rounded in N. midoculi , triangular in N. salazari sp. nov., and in the location of radiolar eyes, mid-region in M. midoculi , 3/4 of the branchial crown length in N. salazari sp. nov.

Figures

FIGURE 11. Notaulax salazari sp. nov. A, D) Base of branchial crown and dorsal flanges (arrows), B, E) same, lateral view, C, F) same, ventral view showing the ventral shield of chaetiger 1 (arrow). Scale bars A – F 1.5 mm. Stain: A – C Shirla, D – F methyl green. Specimen: A – F holotype, UANL 8060.

FIGURE 12. Notaulax salazari sp. nov. A) Rows of radiolar eyespots, B) radiolar tip from dorsal radiole, C) radiolar tip from ventral-most radiole, D) thoracic notochaetae, E) thoracic paleate notochaetae, F) abdominal neurochaetae. Scale bars: A 0.5 mm, B, C 0.25 mm, D, E 50 µm, F 100 µm. Specimen: A – F holotype, UANL 8060.

FIGURE 32. Distribution of some sabellid species in South America. A) Myxicola sulcata Ehlers, 1912, B) Notaulax tilosaula (Schmarda, 1861) (star) and Notaulax salazari sp. nov. (circle), C) Parasabella columbi (Kinberg, 1867) (circles) and Parasabella yonowae sp. nov. (star denotes type locality and triangle indicates additional records).