Laeonereis culveri ( Webster, 1879 )

Conde-Vela, Víctor M., 2021, Revision of Laeonereis Hartman, 1945 (Annelida: Phyllodocida: Gymnonereidinae), with a review of shaft morphology in nereidids, Journal of Natural History 55 (7 - 8), pp. 381-455 : 410-414

Laeonereis culveri ( Webster, 1879)

( Figures 5 (e,h), 6, 13(a–n), and 14(a–m))

Nereis culveri Webster 1879: 111–113 , pl. 3, figs 23–30, pl. 4, figs 31–32. Webster 1886:

140–142, pl. 3(6), figs 23–30, pl. 4(7), figs 31–32. Laeonereis culveri Hartman 1945: 21 . Pettibone 1971: 14–19, figs 5a, b, 6a–l (partim). de

Jesús-Flores et al. 2016: 207–209, fig. 1A–F.

Type material

Northwestern Atlantic Ocean, United States. Syntypes of Nereis culveri USNM 541 (10), Great Egg Harbour, New Jersey, Coll . H .E. Webster . USNM 28178 (11), Beaufort, North Carolina, Coll . C .L. Culver.

Additional material

Northwestern Atlantic Ocean, United States. AMNH 2172 (48), Beaufort, North Carolina, 1934, Coll . A .S. Pearse.

Gulf of Mexico, United States. USNM 22093 (5), Ocean Springs, David Bay, Mississippi, 17 August 1949, Coll . Gulf Coast Research Laboratory . USNM 22243 (3), Sand Beach, Grand Isle, Louisiana, 12 August 1942, Coll . E .H. Behre.

Type locality

Beesley’s Point, Great Egg Harbour, New Jersey.

Description

Syntypes complete, intact and well preserved; one specimen selected for dissection, complete, 48 mm long, 1.8 mm wide, 105 chaetigers ( Figure 13 (a–i)); another one complete, 40 mm long, 1.5 mm wide at chaetiger 10, 115 chaetigers ( Figure 14 (a–d)). Body pale, without pigmentation; greenish glandular masses very conspicuous on both dorsal and ventral sides of body, forming a distinct pattern as follows. In anterior chaetigers, 3–4 well-defined glands on notopodial ligules, one gland on ventral base of parapodium ( Figure 13 (d–e)). In middle chaetigers, 3 well-defined glands on notopodial ligule and a short line on the beginning of parapodium, 1 gland very reduced on ventral base of parapodium, almost inconspicuous ( Figure 13 (f,g)). In posterior chaetigers, 2–3 slightly dispersed glands and three long lines forming a row and crossing each chaetiger, 1 gland reduced on ventral base of parapodium, glands progressively reduced towards posterior end ( Figure 13 (h,i)).

Prostomium as long as wide, anterior margin slightly incised, medial groove present along middle prostomium, reaching posterior pair of eyes ( Figure 13 (a,b)); antennae conical, half as long as prostomium, shorter than palps; eyes sometimes faded ( Figures 13 (a), 14(a)), or with pigment dispersed ( Figure 13 (b)). Achaetous ring 1.5 times longer than first chaetiger ( Figures 13 (a,b), 14(a,c)); four pairs of anterior cirri, cirrophores conspicuous, longest pair reaching chaetiger 4 ( Figures 13 (c), 14(d)).

Pharynx dissected. Jaws brown, cutting edge completely dentate, 10 teeth, some basal teeth ensheathed ( Figure 5 (h)). Maxillary ring: I = 1–1 tuft of verticillate rod-like papillae; II = 1–1 tuft of verticillate rod-like papillae; III = 3 tufts of verticillate rod-like papillae; IV = 1–1 tuft of verticillate rod-like papillae ( Figure 5 (e)). Oral ring: V = 0; VI = 1–1 triangular papilla; VII–VIII = one ridge row with 5 rounded papillae, 1 papilla on each A–C region.

Pattern of pedal glands ( Figure 6 ). UpG subconical and slightly shorter than MeG in anterior chaetigers, becoming oblong and as wide as MeG in middle chaetigers. LoG elliptical and subequal to UpG in anterior chaetigers, dissapearing towards middle chaetigers. MeG elliptical and twice larger than PoG in anterior chaetigers, becoming rounded in middle chaetigers. PoG becoming shorter than middle chaetigers.

First two chaetigers with neuroaciculae only; remaining ones with both noto- and neuroaciculae. In first two chaetigers ( Figures 13 (j), 14(e)), dorsal cirri digitiform. Dorsal ligules subconical, as long as wide, twice as long as dorsal cirri, 1.5 times longer than neuropodial postchaetal lobes. Neuroacicular ligules rounded, as long as wide; postchaetal lobes digitiform, 2–3 times longer than neuroacicular ligules, twice as long as neuropodial ventral ligules; neuropodial ventral ligules subconical, 1.8 times wider than long, twice as long as ventral cirri. Ventral cirri digitiform.

In anterior chaetigers ( Figures 13 (k), 14(f)), dorsal cirri linguiform. Notopodial dorsal ligules lanceolate, twice as wide as long, 6–7 times longer than dorsal cirri, 2.2 times longer than prechaetal lobes, 1.8–2.0 times longer than notopodial ventral ligules; prechaetal lobes digitiform, as long as wide; notopodial ventral ligules digitiform, 1.5 times longer than wide, 1.3 times longer than prechaetal lobes, 1.2 times longer than neuropodial postchaetal lobes. Neuroacicular ligules subconical, blunt, as long as wide, as long as neuropodial ventral ligules; postchaetal lobes digitiform, 1.2 times longer than wide, 1.5 times longer than neuroacicular ligules; neuropodial ventral ligules subconical, blunt, 1.5 times wider than long, 1.7 times longer than ventral cirri. Ventral cirri cirriform.

In middle chaetigers ( Figures 13 (l), 14(g–h)), dorsal cirri linguiform. Notopodial dorsal ligules digitiform, 1.0–1.5 times wider than long, 7–8 times longer than dorsal cirri, 1.2 times longer than notopodial ventral ligules; prechaetal lobes absent; notopodial ventral ligules subconical, 1.2 times wider than long, as long as neuroacicular ligules. Neuroacicular ligules subconical, 2.5 times wider than long, 1.7 times longer than neuropodial ventral ligules; postchaetal lobes absent; neuropodial ventral ligules subconical, as long as wide, 3 times longer than ventral cirri. Ventral cirri digitiform.

In posterior chaetigers ( Figures 13 (m–n), 14(i–j)), dorsal cirri linguiform. Notopodial dorsal ligules subconical, 1.5–1.7 times wider than long, 5 times longer than dorsal cirri, 1.2 times longer than notopodial ventral ligules; prechaetal lobes absent; notopodial ventral ligules subconical, 1.5 times longer than wide, 1.7 times longer than neuroacicular ligules. Neuroacicular ligules subconical, 1.3 times wider than long, twice as long as neuropodial ventral ligules; neuropodial ventral ligules digitiform, 3 times wider than long, 3 times longer than ventral cirri. Ventral cirri digitiform.

In posteriormost chaetigers ( Figure 14 (k,l)), dorsal cirri lanceolate to digitiform. Notopodial ligules absent in posteriormost chaetigers, appearing towards anterior end; notopodial ventral ligules digitiform, twice as long as wide, 2–3 times longer than dorsal cirri. Neuroacicular ligules digitiform, as long as wide, 1.0–1.2 times longer than neuropodial ventral ligules; neuropodial ventral ligules digitiform, 2.5 times wider than long, 1.2 times longer than ventral cirri. Ventral cirri digitiform.

Notochaetae homogomph spinigers. Neurochaetae homogomph spinigers in both supra- and sub-acicular fascicles, few homogomph falcigers in sub-acicular fascicles in middle and posterior chaetigers ( Figure 14 (m)); sub-acicular homogomph falcigers absent in anterior chaetigers.

Neuropodial sub-acicular homogomph falcigers with minute teeth, blades 13–14 times longer than wide, distal tooth hook-like.

Pygidium funnel-shaped; anal cirri cirriform, 3 times longer than the width of pygidium ( Figures 13c , 14d ).

Remarks

Syntypes are very large specimens and have a greenish glandular pattern in both dorsal and ventral sides of the body. The glandular pattern and parapodial morphology are almost identical in the additional material examined; only the body size differs among them, and in some specimens, the greenish glandular pattern is slightly faded out. Specimens have different grades of contraction and their widths vary widely, especially in anterior segments; however, parapodial proportions are consistent in all cases, making misidentification difficult. Mazurkiewicz (1975, 2009) detailed the early development and ontogeny of parapodia and chaetae of this species, it being the only one in the genus with information available in these areas.

This species has been often confused with other Laeonereis species , after Pettibone (1971), and recorded from several localities. Hartman (1948) compared Laeonereis with Neanthes Kinberg, 1865 in terms of having homogomph spinigers in notopodia and homogomph spinigers and both homogomph and heterogomph falcigers in neuropodia. This idea led Hartmann-Schröder (1959) to propose a new genus for her new species L. brunnea ; however, no heterogomph falcigers were found in the species revised in the present study. Differences among L. culveri and the remaining species of the genus had been pointed out by other authors (e.g. de Jesús-Flores et al. 2016; de León-González et al. 2017), and are noted here in the Remarks section for each species.

Material illustrated by Pettibone (1971) for Sapelo Island, Georgia ( USNM 33294 ), and regarded as L . culveri, displays several differences from the type material examined. The main differences are focused on the distinct glandular pattern ( Figure 6 ) and the relative size of notopodial dorsal ligules along the body . Therefore , the specimens from Georgia are here considered a distinct species, Laeonereis longula sp . nov. Records of L . culveri from the Caribbean Sea (Dean 2012) deserve a new evaluation to confirm that they belong to this species .

Figures

Figure 5. Foregut, papillae and jaws in Laeonereis species. (a) non-type specimen of L. acuta (ECOSUR- P3102), ventral dissection; (b) non-type specimen of L. pandoensis (ECOSUR-P3103), dorsal dissection; (c) and (d) rounded papillae in area VIII from paratype of L. orensanzi comb. nov. (UANL 7840); (e) rodlike, verticillate papillae from syntype of L. culveri from area IV (USNM 541); (f) everted pharynx from paratype of L. longula sp. nov. (USNM 1490792), labels indicate papillae on the pharyngeal areas; (g) left jaw of the paratype of L. brunnea (USNM 43404), dorsal view; (h) left jaw of the syntype of L. culveri (USNM 541), dorsal view; (i) left jaw of the paratype of L. longula sp.nov. (USNM 1490792), dorsal view; (j) left jaw of L. orensanzi comb. nov. (UANL 7840), dorsal view; (k) left jaw of non-type of L. pandoensis (ECOSUR-P3103), dorsal view. Dark areas in (a) and (b) are due to remnants of Shirlastain staining; (f) is stained with methyl green. Scale bars: a, b = 0.5 mm; c–e, j = 25 µm; f–i, k = 0.1 mm. Abbreviations:Es, oesophagus; Jw, jaw; Pa, papilla; Ph, pharynx; Pp, palpophore; Ps, palpostyle.

Figure 6. Arrangement of pedal glands in Laeonereis species. Abbreviations: DoG = dorsal gland; LoG = lower distal pedal gland; MeG = medial pedal gland; PrG = proximal pedal gland; UpG = upper distal pedal gland.

Figure 13. Laeonereis culveri (Webster, 1879). (a–n), syntypes of Nereis culveri (USNM 541). (a) anterior end, dorsal view; (b) anterior end, dorsal view; (c) posterior end, dorsal view; (d) anterior chaetigers, dorsal view; (e) same, ventral view; (f) mid chaetigers, dorsal view; (g) same, ventral view; (h) midposterior chaetigers, dorsal view; (i) same, ventral view; (j) chaetiger 2, right parapodium; (k) chaetiger 10, right parapodium; (l) chaetiger 41, right parapodium; (m) chaetiger 82, right parapodium; (n) chaetiger 102, right parapodium. Scale bars: a–b = 2 mm; c–i = 1 mm; j–n = 0.3 mm.

Figure 14. Laeonereis culveri (Webster, 1879). (a–m), syntypes of Nereis culveri (USNM 541). (a) anterior end, dorsal view; (b) posterior end, dorsal view; (c) anterior end, dorsal view; (d) posterior end, dorsal view; (e) chaetiger 2, right parapodium; (f) chaetiger 10, right parapodium; (g) chaetiger 30, right parapodium; (h) chaetiger 52, right parapodium; (i) chaetiger 80, right parapodium; (j) chaetiger 100, right parapodium; (k) chaetiger 109, right parapodium; (l) chaetiger 111, right parapodium; (m) subacicular homogomph falciger, chaetiger 30. Scale bars: a–d = 0.5 mm; e, j–l = 0.1 mm; f– i = 0.2 mm; m = 10 µm.