Paratherochaeta augeneri, Salazar-Vallejo, 2013

Salazar-Vallejo, Sergio I., 2013, Revision of Therochaeta Chamberlin, 1919 (Polychaeta: Flabelligeridae), Zoosystema 35 (2), pp. 227-263 : 250-251

Paratherochaeta augeneri n. sp.

( Fig. 9 )

Stylarioides scutigeroides Augener, 1918: 444-447 , pl. 6, figs 155, 185 (partim). — Tebble 1955: 127-128 (partim, not Stat. 55), fig. 28. — Kirkegaard 1959: 43 (partim).

Stylarioides (?) scutigeroides – Amoureux 1973: 61 (non Augener 1918).

Pherusa scutigeroides – Intes & leLoeuff 1977: 236 (non Augener 1918).

TYPE MATERIAL. — Tropical Eastern Atlantic Ocean. Holotype ( ZMUC 1786 ) and paratype (ZMUC 1787), off Monrovia (06°18’48”N, 10°48’05”W), Liberia, R/V Atlantide, Stat. 52 (no coordinates), 11 m, 3.I.1946 (paratype is an anterior fragment, damaged, 8 mm long, 3 mm wide, cephalic cage (broken) 1.5 mm, 15 chaetigers).

ADDITIONAL MATERIAL. — Tropical Eastern Atlantic Ocean.Four specimens ( BMNH 1953.3.1.904), damaged, partially dehydrated, two complete, off Accra, Ghana, Stat. 69, 14 km WSW Accra Lighthouse, 22 m, 22.I.1951, R. Bassindale coll. (5.0- 5.5 mm long, 1.0- 1.5 mm wide, cephalic cage 2 mm long, 17-19 chaetigers).

ETYMOLOGY. — This species is named after Hermann Augener, who made many monographic papers on polychaetes, including the now famous one on Western Africa. In most of his publications, he attempted to examine type material to confirm previous descriptions. Regretfully, this legacy is not yet a widespread practice among polychaete taxonomists.

TYPE LOCALITY. — Off Monrovia, Liberia, Western Africa.

DISTRIBUTION. — Tropical and subtropical Western Africa, from Morocco to Angola, in shallow water (3-50 m).

DESCRIPTION

Holotype and paratype completely covered by sediment grains ( Fig. 9A ), becoming less abundant posteriorly. Body medially swollen, anteriorly and posteriorly tapered. Tunic thick, with sediment particles forming sediment tubercles (holotype sediment cover removed). Holotype 15 mm long, 3 mm wide, cephalic cage (broken) 3 mm long, 47 chaetigers. Anterior end not dissected to avoid further damage.

Cephalic cage damaged, chaetae about as long as body width (before removing the sediment cover). Chaetigers 1-2 involved in cephalic cage; chaetiger 3 with chaetae twice as long as those in chaetiger 4, but not contributing to cage. Cephalic cage chaetae arranged in short series, surrounding anterior end. Chaetiger 1 with three noto- and two neurochaetae per bundle; chaetiger 2 with about six chaetae per bundle.

Anterior dorsal margin of first chaetiger depressed, without lobes (ventrally with two triangular blunt lobes, Fig. 9B ). Anterior chaetigers with long papillae in chaetal lobes; in chaetigers 3-4 papillae arranged in single transverse bands per segment; each papillae making a large tubercle, fusing to form a crown. Chaetigers 1-2 elongating posteriorly; constriction in chaetigers 2 and 3.

Sand cemented anterior shield surrounding chaetigers 1-4, stiff; following chaetigers with sediment cover continued but flexible, not stiff. No chaetal transition from cephalic cage to body chaetae; all neurochaetae multiarticulated capillaries. Gonopodial lobes in chaetiger 4 ( Fig. 9B [arrows]).

Parapodia better developed in anterior chaetigers, foliose lobes; other parapodia reduced, chaetae emerging from body wall. Parapodia lateral; median neuropodia ventrolateral. Noto- and neurochaetae low lobes; without long papillae, two interramal long papillae. Noto- and neuropodia distant to each other.

Median notochaetae arranged in short longitudinal series; all multiarticulate capillaries, five-six per bundle, about as long as 1/5 body width (with sediment cover) or about 1/3 body width (without sediment cover). Neurochaetae all multiarticulated aristate capillaries, reddish basally, articles medium-sized continued to tip, four in anterior chaetigers, up to nine in posterior chaetigers ( Fig. 9C ), arranged in a ∪-pattern.

Posterior end with sediment particles over body wall, becoming less abundant towards pygidium; anus terminal, no anal cirri ( Fig. 9D ).

REMARKS

Paratherochaeta augeneri n. sp. belongs to Paratherochaeta n. gen. because it lacks pseudocompound hooks; P. augeneri n. sp. is the only species of the genus having a tunic with large sediment tubercles and multiarticulated capillaries in all neuropodia, as originally illustrated by Tebble (1955: 129, fig. 28).

Figures

FIG. 9. — Paratherochaeta augeneri n. sp.; A, paratype (ZMUC 1787),left,and holotype (ZMUC 1786),right,dorsal views;B-D, holotype, sediment tubercles removed (arrow points gonopodial lobes); C, chaetiger 16, right parapodium, neurochaetae; D, posterior region. Scale bars: A, 0.5 mm; B, 1.3 mm; C, 60 µm; D, 0.8 mm.