Notaulax tilosaula ( Schmarda, 1861 ) Schmarda, 1861

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 : 21-24

Notaulax tilosaula ( Schmarda, 1861) , new combination

( Figs 9 , 10 , 32 B)

Sabella tilosaula Schmarda, 1861: 34 , pl. 23, fig. 191, text fig. a–d.— Ehlers 1901: 216.— Perkins 1984: 328.

Material examined. CHILE, ( UANL 8057, 8058 ), Puerto de Valparaíso , Chile, 33°02’09.76’’S, 71°37’37.30’’W, dock fouling, 13 m depth, 19 April 2005, coll. E. Schwindt & L. Prado, 2 specimens . PERU, UANL 8059 , Callao, Crab trap, 25 August 1977, 1 specimen. Sabella phaeotaenia Schmarda, 1861 , syntype , NHMW 1902, only trunk, branchial crown not preserved. Sabella tilosaula Schmarda, 1861 , NHMW 1733, labelled as type but instead a member of Terebellidae .

Redescription (based on specimens from Valparaíso). Trunk length 7.6 – 8 cm, width 3 – 4 mm. Branchial crown length 15 – 18 mm, with 18 pairs if radioles. Eight to 15 thoracic chaetigers, number of abdominal segments not determined (posterior abdomen inside tubes). Branchial lobes joined mid-dorsally. Basal lamina as long as length of collar segment in lateral view ( Fig. 9 B). Base of branchial crown with flanges; dorsal ones prominent ( Fig. 9 A, D), triangular in side view ( Fig. 9 B), ventral flanges reduced. Radioles arranged in two semicircles, not involuted mid-ventrally and joined by palmate membrane extending 1/4 length of branchial crown. Outer margins of radioles flat, with broad flanges extending only from distal-most eyes to radiolar tips. Radiolar tips short, occupying space of three pinnules width ( Fig. 10 D). Two rows of 30 – 38 lensed eyes, beginning above palmate membrane and extending 1/2 branchial crown length, present on all radioles ( Fig. 9 E, F). Dorsal lips long, extending to end of palmate membrane, triangular with radiolar appendage. Ventral lips short, rounded lobes. Ventral radiolar appendages and dorsal radiolar appendages all absent. Parallel lamellae and ventral sacs present, between branchial lobes. Dorsal margins of collar diagonal, fused to faecal groove ( Fig. 9 A, D). Lateral collar margins oblique (or V-shaped) ( Fig. 9 B). Ventral collar lappets triangular, distal margins rounded with short incision, not longer than 1/4 ventral length of collar ( Fig. 9 C); below incision, a pair of small diagonal lines of cilia is present. Ventral shield of chaetiger 1 divided transversely in two rectangular glandular areas with diagonal lateral margins, anterior glandular area narrower than posterior ( Fig. 9 C). Subsequent ventral shields entire, nearly trapezoidal, laterally indented by neuropodial tori ( Fig. 9 C). Chaetiger 1 with pair of long, slightly oblique longitudinal row of more than 45 spine-like notochaetae. Remaining thoracic notopodia with superior broadly hooded chaetae ( Fig. 10 E), inferior paleate, without mucros ( Fig. 10 E, F). Neurochaeta avicular uncini, with medium-sized handles, developed breast and several rows of minute, similar-size teeth above main fang; neuropodial companion chaetae with rounded denticulate head and long, gently tapering asymmetrical membrane ( Fig. 10 G). Abdominal segments with interramal eyespots ( Fig. 10 C). Avicular abdominal uncini similar to thoracic; neuropodial tori with five abdominal paleate neurochaetae with long mucros ( Fig. 10 H) and 5 needle-like chaetae, posterior to paleae, two times longer than paleae. Pygidial eyespots not observed. Tubes fibrous, with rough outer surfaces ( Fig. 10 A, B), 10 – 13 cm long, 3 mm wide in distal portion, narrower towards basal region. Tube walls composed of several layers, externally brown, internally olive-green. One specimen male (UANL 8057) with a dense spermatic mass in the abdomen, as well as patches of sperm attached to the interior sides of the tube, spermatozoa have rounded heads and long flagella. The additional specimen fromValparaíso (UANL 8058) is a female with an abdomen full of oocytes.

Type locality. Chile (no more information provided by Schmarda 1861).

Remarks. Notaulax tilosaula was described from the Chilean coast and illustrated by Schmarda (1861: pl. 23, fig. 191, text fig. a–d). The specimen reported by Kinberg (1867: 354) as Demonax tilosaulus (not Sabella tilosaula Schmarda, 1861 ) is a Chone species according to Hartman (1959: 514). Hartman (1959: 565) stated that N. tilosaula is possibly Sabella phaeotaenia Schmarda (currently recognized in Notaulax ), a species described from Ceylon, but Perkins (1984) recognized them as different valid species, as is shown herein. In 2010, one of us (MAT-H) examined one specimen labeled as the type of Sabella tilosaula Schmarda (NHMW 1733), which was determined to be a member of the Terebellidae . The specimens reviewed here fits completely the original description and illustrations by Schmarda for N. tilosaula , and it has a set of unique features that allow a clear separation from N. phaeotaenia .

The syntype of Notaulax phaeotaenia revised in this study (NHMW 1902) has a very long basal lamina (as long as the thorax) and the ventral margins are entire, very shallow, angle almost horizontal, while in N. tilosaula the basal lamina is short (as long as the collar segment) and the ventral margins are incised, long, projected. The lateral collar margin in N. phaeotaenia is even (V-shaped in N. tilosaula ). Live color of both species are different: N. phaeotaenia has a red branchial crown with alternating yellow bands, while in N. tilosaula the crown is entirely red. Although chaetae and uncini of both species were not compared, the differences stated above are sufficient to consider both species separately.

There are some records of N. phaeotaenia in South America, particularly from Patagonia ( Hartmann-Schröder 1983; Montiel et al. 2004, 2011; Rios et al. 2005), but these might be erroneous since the type locality (Ceylon, current Sri Lanka) has environmental conditions completely different from those in Patagonia and specimens have never been properly compared. A reexamination of these specimens is recommended.

The presence of interramal eyespots ( Fig. 10 C) has never been described among members of Notaulax . In the current study, these structures are reported for N. tilosaula .

Figures

FIGURE 9. Notaulax tilosaula (Schmarda, 1861). A) Base of branchial crown and anterior thoracic segments, dorsal view, B) same, lateral view, C) same, ventral view showing the ventral shield of chaetiger 1 (arrow), D) collar and base of branchial crown, E) palmate membrane (arrow), F) distribution of lensed eyespots. Arrows in A, B pointed to dorsal flanges. Scale bars: A – D 2 mm, E, F 1.0 mm. Specimen: A – F UANL 8057.

FIGURE 10. Notaulax tilosaula (Schmarda, 1861). A, B) Tree bark appearance of tubes, C) abdominal interramal eyespots, D) pinnules and radiolar tip, E) thoracic broadly hooded notochaetae, F) thoracic paleate notochaetae, G) companion chaeta, H) abdominal paleate neurochaetae. Scale bars: A, B 4.2 mm, C 0.8 mm, D 1 mm, E, F 50 µm, G 20 µm, H 100 µm. Specimens: A, B UANL 8058, C – H UANL 8057.

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).