Nereis callaona Grube & Kröyer

Salazar-Vallejo, Sergio I., León-González, Jesús Angel De & Conde-Vela, Víctor M., 2021, Revision of the species confused with “ Nereis falsa ” de Quatrefages, 1866 (Annelida, Nereididae), European Journal of Taxonomy 779, pp. 1-70 : 20-23

Nereis callaona Grube & Kröyer in Grube, 1857

Fig. 7

Nereis (Nereilepas) callaona Grube & Kröyer in Grube, 1857: 165–166.

Nereis robusta Kinberg, 1866: 168–169 .

Nereis pseudonereis Hartman, 1940: 223–224 , pl. 36 figs 63–64, pl. 37 figs 65–66.

Nereis callaona – Ehlers 1901b: 108–110, pl. 13 figs 13–20. — Hartman 1940: 227. — Fauvel 1943: 15. — Reish 1954: 104–105, pl. 24 figs 13–14 (synonymy). — Hartmann-Schröder 1960: 19–20, figs 38–39; 1962a: 399–400; 1962b: 107. — Wesenberg-Lund 1962: 297; 75, fig. 28. — Rozbaczylo & Bolados 1980: 209–212, fig. 2 (synonymy). — Salazar-Vallejo & Eibye-Jacobsen 2012: 1396 (gave incorrect publication year).

Nereis robusta – Kinberg 1910: 50, pl. 20 fig. 1. — Hartman 1948: 64–66, pl. 10 figs 10–11.

Nereis falsa – Berkeley & Berkeley 1964: 129 (non de Quatrefages, 1866).

Diagnosis

Nereis with posterior eyes completely exposed; tentacular belt 1.5 × as long as first chaetiger; tentacular cirri short, reaching chaetigers 4–5; jaws with 4 teeth; pharyngeal area II with 11 paragnaths in 2 rows, areas VII–VIII with 2–3 transverse rows of paragnaths; anterior chaetigers with notopodial ligules short, globose; ventral ligules in median and posterior chaetigers markedly longer than neuracicular ligules.

Material examined

Holotype

PERU • adult; Callao; 18 Sep. 1848; Kröyer leg. (according to Salazar-Vallejo & Eibye-Jacobsen 2012: 1396; no specimens in Berlin or Wroclaw ( Hartwich 1993; Wiktor 1980)); NHMD 109278 (previously ZMUC POL-1495).

Holotype of Nereis pseudonereis ECUADOR • Galapagos Islands, “Albemarle Island” [now Isabela Island], Tagus Cove ; 00°16′26″ S, 91°22′42″ W; R/V Velero III, stn 326-34; sand, bryozoans; 27 m depth; 10 Dec. 1934; Allan Hancock Foundation leg.; LACM 824 (not seen).

Description

BODY. Holotype ( NHMD 109278 ) atoke, complete, 43 mm long, 2.5 mm wide including parapodia, with 75 chaetigers. All parapodia with dark brown glandular masses.

PROSTOMIUM. Pyriform, longer than wide; eyes round, of similar size, in trapezoidal arrangement, posterior eyes closer to each other ( Fig. 7A ). Antennae swollen basally, as long as palps, without gap between them. Palpophores globose, 1.5× as long as wide, palpostyles rounded.

TENTACULAR BELT. 1.5× as long as first chaetiger, anterior margin not covering posterior eyes. Tentacular cirri smooth, longest ones reaching chaetiger 4 ( Fig. 7A ).

PHARYNX. Everted. Jaws brown with 4 teeth ( Fig. 7A, C ). Paragnath formula: I: 2 in tandem; II: 11 in two rows; III: 40 in 4 rows, forming almost oval group; IV: 25–30 in crescent-shaped groups; V: 0; VI: 4 in diamond; VII–VIII: two rows, anterior row with 29 large cones, almost in zig-zag arrangement, posterior row with 29 small cones in a row ( Fig. 7A–C ).

PATTERN OF PARAPODIAL LIGULES. Anterior chaetigers with ligules blunt, globose, as long as wide, becoming digitate, 2–3× as long as wide in median and posterior chaetigers; ventral ligule slightly longer than neuracicular ligules in anterior chaetigers, in median and posterior ones markedly longer than them.

CHAETIGERS 1–2. With neuraciculae only; with both noto- and neuraciculae thereafter.

ANTERIOR PARAPODIA ( Fig. 7D ). With dorsal cirrus inserted medially, longer than ventral ones; dorsal and median ligules rounded, subequal; dorsal ligule 1.7× as long as wide; median ligule as long as wide, 2 × as long as neuracicular ligule; prechaetal lobe rounded, small. Neuracicular ligule rounded, as long as wide; ventral ligule digitiform, 1.6× as long as wide, 2 × as long as neuracicular ligule, longer than ventral cirrus. Notochaetae 10–11 homogomph spinigers. Supracicular neurochaetae: 7 homogomph spinigers and 4 thick heterogomph falcigers with blades 4 × as long as wide, denticulate along cutting edge, distal tooth incurved, fused to blade ( Fig. 7G ); subacicular neurochaetae: 3 heterogomph spinigers and 10 heterogomph falcigers with blades 6× as long as wide, distal tooth incurved, fused to blade ( Fig. 7H ).

MEDIAN PARAPODIA ( Fig. 7E ). With dorsal cirrus longer than ventral one, both slightly thin, dorsal cirrus 2 × as long as dorsal ligule; dorsal and median ligules subequal, digitiform, 1.3× as long as wide, 3× as long as neuracicular ligule. Neuracicular ligule subconical, 2 × as wide as long; ventral ligule 2.5 × as long as wide, 3× as long as neuracicular ligule, subulate. Notochaetae: 3 homogomph spinigers and 1 homogomph falciger, slightly denticulate along cutting edge, distal tooth incurved and fused to blade. Supracicular neurochaetae: 4 homogomph spinigers and 3 heterogomph falcigers with blades 4× as long as wide, distal tooth incurved, fused to blade; subacicular neurochaetae: 1 heterogomph spiniger and 5 heterogomph falcigers with blades 4× as long as wide, distal tooth incurved, fused to blade ( Fig. 7I ).

POSTERIOR PARAPODIA ( Fig. 7F ). With dorsal cirrus inserted medially, longer than ventral one; dorsal ligule basally swollen, distally digitiform, 4× as long as wide, 1.5 × as long as median one; median ligule digitiform, 3 × as long as wide, 3.2× as long as neuracicular ligule. Neuracicular ligule subconical; ventral ligule digitiform, 3 × as long as neuracicular ligule. Notochaetae: 1 homogomph spiniger and 2 homogomph falcigers, 6.5× as long as wide ( Fig. 7K ), similar to those of median parapodia. Supracicular neurochaetae: 5 homogomph spinigers and 1 heterogomph falciger with blade 3.4× as long as wide, distal tooth incurved, fused to blade, cutting edge with a few denticles ( Fig. 7J ); subacicular neurochaetae: 4 heterogomph falcigers with blades 4× as long as wide, distal tooth incurved and fused to blade.

POSTERIOR REGION. Tapered. Pygidium with terminal anus and two anal cirri.

Remarks

Nereis callaona was described based on specimens from El Callao port, Peru. It differs from other species in the group by the presence of massive, dark glands in parapodial ligules throughout the body. The record by Augener (1918) for West Africa resembles typical specimens because it has the posterior eyes exposed, pharyngeal areas VII–VIII with 2–3 rows of denticles and pigmented glandular areas in posterior parapodia. They differ, however, because the Eastern Pacific species has 11 paragnaths in two rows in pharyngeal area II, whereas the West African form has 28 paragnaths in three rows in the same area. Reish (1954) regarded N. pseudonereis Hartman, 1940 , described from the Galapagos and Peru, as a junior synonym of N. callaona after a comparison of the type specimens (see above). We follow Reish’s conclusion.

Nereis callaona was regarded as identical to N. falsa by Berkeley & Berkeley (1964), probably following Hartman (1940: 224), who indicated some affinities of her N. pseudonereis , a junior synonym of N. callaona (as indicated above), with N. falsa . However, the status of this latter species has been confused, because it belongs in Hediste Malmgren, 1867 (see above).

Further confusion was introduced by Ehlers (1913) by recording N. splendida Grube, 1840 from Southern Africa. However, N. callaona differs from N. splendida by having dark glandular masses in the parapodial ligules. Augener (1918) recorded N. callaona , from Western Africa, and although specimens of this latter region were not seen, they differ in the number of paragnaths in area II. There are 11 cones in the American specimens and 28 in the African ones. On the other hand, the male epitoke reported as N. falsa by Berkeley & Berkeley (1964) has 26 chaetigers in the pre-natatory region instead of 27, as indicated for “ N. falsa ” by Fauvel (1923: 338). Their account should be referred to N. callaona , as indicated above, and not to any other species.

Distribution

Galapagos Islands, Ecuador, to northern Chile, in shallow water (0–30 m depth).

Figures

Fig. 7. Nereis callaona Grube & Kröyer in Grube, 1857, holotype (NHMD 109278). A. Anterior end, oblique dorsal view. B. Same, close-up of pharynx. C. Pharynx, oblique ventral view. D. Chaetiger 10, right parapodium, anterior view. E. Chaetiger 31, right parapodium, anterior view. F. Chaetiger 61, right parapodium, anterior view. G. Chaetiger 10, neuropodial supracicular heterogomph falciger. H. Chaetiger 10, neuropodial infracicular heterogomph falciger.I. Chaetiger 31, neuropodial subacicular heterogomph falciger. J. Chaetiger 61, neuropodial supracicular heterogomph falciger. K. Same, notopodial homogomph falciger.