Lepidonopsis humilis ( Augener, 1922 )

Salazar-Silva, Patricia & Carrera-Parra, Luis Fernando, 2014, Revision of Lepidonopsis humilis (Augener, 1922) and description of L. barnichae sp. nov. (Annelida: Polychaeta: Polynoidae) based upon morphological and molecular characters, Zootaxa 3790 (4), pp. 555-566 : 557-561

Lepidonopsis humilis ( Augener, 1922)

Figures 1–3

Lepidonotus humilis Augener, 1922: 40 ; Augener 1933: 194 –195; Hartman 1944: 9.

Lepidonopsis humilis .— Pettibone 1977: 50 –54, figures 5a–f (partim); Jiménez-Cueto & Salazar-Vallejo 1991:148.

Material examined. Type material: Syntype ZMB 6262, Dry Tortugas, Florida, USA, coll. Hartmeyer, one spm. Syntype ZMB 6263, Kingston, Jamaica, coll. Kükenthal and Hartmeyer, one spm.

Additional material. Northwestern Atlantic Ocean: North Carolina: 56 mi South Beaufort, mouth of New River, Black Rocks reefs, 34°30′36″ N 77° 19′ 36″ W, 3.6 – 7 m, coll. A.S. Pearse, 19 Jun. 1949, as Lepidonotus variabilis Webster, 1879 , LACM-AHF Poly 6202, 2 spm. Black Rocks off New River, 34°30′36″ N 77° 19′ 36″ W, 6 mi off shore, 13.7 m, coll. A.S. Pearse, 9 Aug. 1959, as L. variabilis Webster, 1879 , LACM-AHF Poly 6203, 1 spm. Black Rocks off New River, 34°30′36″ N 77° 19′ 36″ W, coll. A.S. Pearse, 22 Jul. 1949, as L. variabilis Webster, 1879 , LACM-AHF Poly 6204, 1 spm. Bogue Sound, near Morehead City, 34°43′38″ N 76°40′ 33″ W, 15 Jun. 1940, as L. variabilis , LACM-AHF Poly 6209, 1 spm. Gulf of Mexico, Florida: Thornton Island, near Englewood, 26°53′32″ N 82°20′ 20″ W, in crevices on outer side, 15 Jun. as L. variabilis Webster, 1879 , LACM- AHF Poly 6205, 1 spm. Lemon Bay, 26°54′50″ N 82° 20′ 26″ W, trawled from ascidians bed, in 0.3 m of water, 24 Jan. 1938, as L. variabilis Webster, 1879 , LACM-AHF Poly 6206, 10 spm. Thornton Island, 26°53′32″ N 82°20′ 20″ W, 25 Jan. 1938, as L. variabilis Webster, 1879 , LACM-AHF Poly 6207, 1 spm. Colombia: 11 miles southwest of Cape la Vela, 12°04′30″ N 72°14′ 45″ W, 7 Apr. 1937, Velero III, as Lepidonotus humilis Augener 1922 , LACM-AHF-Poly 6208, 1 spm. Yucatan, Mexico: Celestun, CEL-5, over dock pillings. coll. S.I. Salazar- Vallejo and R. Bastida, 17 Feb. 1999, ECOSUR-P1374, 1 spm. San Felipe, 21°35′9.9″ N 88°13′ 55″ W, 500 m off Punta San Felipe, in coralline rock, 2.5 m, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 16 Jun. 2009, ECOSUR- OH-P634, 1 spm. Ría Lagartos, LAG-1, 1.5 km off Ría Lagartos, in coralline rock, 2–4 m, coll. S.I. Salazar-Vallejo and R. Bastida, 18 Feb. 1999, ECOSUR-P1387, 1 spm. Ría Lagartos, LAG-1, 1.5 km off Ría Lagartos, in coralline rock, 2–4 m, coll. S.I. Salazar-Vallejo and R. Bastida, 18 Feb. 1999, ECOSUR-P1373, 2 spm. Ria Lagartos, Yucatan, Mexico 21°37′50.11″ N 88°9′ 5.7″ W, 1 km off Rio Lagarto Beach, in rock, 3 m, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 14 Jun. 2009, ECOSUR-OH-P619, 1 spm. Ria Lagartos, 1 km off Rio Lagartos Beach, 21°37′50.11″ N 88°9′ 5.7″ W, in rock, 3 m, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 14 Jun. 2009, ECOSUR- OH-P567, 1 spm. Ria Lagartos, 1 km off Rio Lagartos beach, 21°37′50.11″ N 88°9′ 5.7″, in rock, 3 m, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 14 Jun. 2009, ECOSUR-OH-P556, 1 spm. Ria Lagartos, 1 km off Ria Lagartos beach, 21°37′50.11″ N 88°9′ 5.7″, in rock, 3 m, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 14 Jun. 2009, ECOSUR-OH-P536, 1 spm. Quintana Roo, Mexico: Holbox Island, 21°31′8″ N 87°22′ 26″ W, station Blanquizal, in coralline rock, 3 May. 2000, ECOSUR-P1365, 1 spm. Contoy Island, Northern point over dock pilling, Xylobiont, 21°31′43.8″ N 86°48′ 10.1″ W, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 23 Feb. 2008, ECOSUR-OH-P0261, 1 spm. Contoy Island, 21°30′8″ N 86°47′ 45″ W, in conch of Strombus gigas , coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 15 Jun. 1999, ECOSUR-P1362, 11 spm. Contoy Island, 21°30′8″ N 86° 47′ 45″ W, in coralline rock, 23 Mar. 1999, ECOSUR-P1363, 1 spm. Contoy Island, 21°30′8″ N 86°47′ 45″ W, 28 Feb. 2001, ECOSUR-P1366, 1 spm. Contoy Island, Puerto Viejo lagoon, 21°29′19″ N 86°47′ 32.1″ W, in mangrove root, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 24 Feb 2008, ECOSUR-OH P0262, 1 spm. Contoy Island, 21°30′8″ N 86°47′ 45″ W, station Camping, 1 m, in coralline rock, 1 Mar. 2001, ECOSUR-1369, 4 spm. Contoy Island, 21°30′8″ N 86° 47′ 45″ W, station Camping, in conch, coll. S. Salazar and R. Bastida, 0 1 Mar. 2001, ECOSUR-P1391, 1 spm. Contoy Island, 21°30′8″ N 86°47′ 45″, station Camping, in coralline rock, 28 Feb. 2001, ECOSUR-P1392, 1 spm. Contoy Island, Camping Beach, in sponge, 21°28′28.9″ N 86°47′ 22.5″ W, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 25 Feb. 2008, ECOSUR-OH-P0257, 1 spm. Contoy Island, 21°30′8″ N 86° 47′ 45″ W Punta Sur, in coralline rock, 28 Feb. 2001, ECOSUR-P1385, 1 spm. Contoy Island, Ixlache reef, in coralline rock, 21°26′2.5″ N 86°46′ 56.1″ W, 3 m, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 25 Feb. 2008, ECOSUR-OH-P0258, 1 spm. Contoy Island, Ixlache reef, in coralline rock, 21°26′2.5″ N 86°46′ 56.1″ W, 3 m, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, 25 Feb. 2008, ECOSUR-OH-P0256, 1 spm. Isla Mujeres, Bajo Pepito, Sta. Blanquizal, coll M. Díaz, in Udotea, Mar 1997 , ECOSUR-P1376, 1 spm. Punta Nizuc, Cancun, 21°1′23″ N 86°46′ 52″ W, in coralline rock, R4, 2.2 m, 31 Aug. 1997, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, ECOSUR- P1377, 3 spm. Punta Nizuc, Cancun, 21°1′23″ N 86°46′ 52″ W, on coralline rock, R5, 2.6 m, 31 Aug. 1997, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, ECOSUR-P1378, 1 spm. Punta Nizuc, Cancun, 21°1′23″ N 86°46′ 52″ W, on coralline rock, R8, 4 m, 1 Sept. 1997, coll. S.I. Salazar-Vallejo & L.F. Carrera-Parra, ECOSUR-P1379, 3 spm. Punta Nizuc, Cancun, 21°1′23″ N 86°46′ 52″ W, on coralline rock, R9, 4 m, 1 Sept. 1997, coll. S.I. Salazar- Vallejo & L.F. Carrera-Parra, ECOSUR-P1381, 3 spm. Cayo Valencia, Ascención Bay, in root of Rhizophora mangle , 29 Apr. 1987, coll. E. Donath & S. Jiménez, ECOSUR-P1375, 2 spm. Mahahual, 18°40′9″ N 87°43′ 1″ W, coll. S.I. Salazar-Vallejo, in conch of Strombus gigas , 18 May. 2002, ECOSUR-P1364, 1 spm. Chinchorro Bank, North Blackford Cay, R/V Edwin Link, Sta. 2780, 18°30′94″ N 87°26′ 61″ W, 61 m, ECOSUR-P2433, 1 spm.

Diagnosis. Two small nuchal lobes on the middorsal area of segment two ( Fig. 1 B), Elytra with hemispherical macrotubercles and microtubercles with protuberances on their surface ( Fig. 3 E), first three pairs of elytra with macrotubercles larger than in remaining elytra and neurochaetae with bidentate tip ( Figs. 2 F, 3F).

Description. Based on syntype ZMB 6262; complete with 26 segments, some elytra detached. Body of uniform width, length 9 mm, width 2 mm. (Syntype ZMB 6263 broken in two fragments. Coloration pattern faded.)

Prostomium bilobed, wider than long, without prostomial peaks. Median antenna with ceratophore inserted frontally, style missing; two lateral antennae with ceratophores inserted terminally, fused to distal end of prostomium as prolongations of prostomial lobes; styles missing. Two pairs of eyes, both pairs dorsolateral on posterior half of prostomium, anterior pair at widest part of prostomium, posterior pair smaller, near posterior margin. Palps smooth, thick, with abruptly tapering tips, appearance like a small palpostyle; about 1.5 times prostomium length. Pharynx not everted. Tentacular segment not visible dorsally; tentaculophores inserted lateral to prostomium, slender chaetae present. Tentacular cirri missing. Segment 2 with two small lobes middorsally ( Fig. 1 B). First pair of parapodia directed forward; ventral oral cirri longer than following.

Elytra 12 pairs, on segments 2, 4, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23; last three segments with dorsal cirri. Elytra covering dorsum completely; overlapping medially and posteriorly; with brown spots on surface, near elytrophore ( Fig. 1 A). First pair of elytra circular, smaller than remaining; with fringe of thick filiform papillae; tuft of short papillae on dorsal surface, isolated from marginal papillae. Digitiform micropapillae, sclerotized macrotubercles and microtubercles on dorsal surface of elytra ( Fig. 2 A). Macrotubercles hemispherical ( Figs. 2 A, 3E) covered by small nodules, the largest over elytrophore area. Microtubercles of similar shape as macrotubercles, flattened towards anterior half; few conical truncated microtubercles close to elytra edge ( Fig. 2 B). Second and third pair of elytra reniform ( Fig. 3 B–C), remaining elytra oval ( Fig. 3 D); with marginal papillae; tuft of papillae on dorsal surface absent; surface covered with microtubercles and sclerotized macrotubercles. Macrotubercles over elytrophore area, hemispherical, covered by small nodules, shorter than on first pair of elytra. Microtubercles similar to macrotubercles, shorter where elytra overlap.

Parapodia biramous, notopodia shorter than neuropodia. Neuropodia with prechaetal lobe slightly projecting; postchaetal lobe shorter than prechaetal lobe, distally rounded with filiform papillae ( Figs. 1 C–D, 2C–D). Dorsal cirri with cirrophore expanded basally, style slender with middle region expanded, tapering to filiform tip ( Fig. 1 C); surface smooth, without papillae, slightly pigmented. Elytrophores wider than dorsal tubercles. Notochaetae shorter than neurochaetae, with rows of spines, slender, tapering to capillary tip ( Fig. 2 E). Neurochaetae thicker than notochaetae, 2–3 rows of spines on the distal part, tips bidentate, main tooth thicker and longer than subdistal tooth ( Figs. 2 F, 3F). Nephridial papillae from segment 11. Anus dorsal; anal cirri missing.

Variation. Specimens examined varied in length from 0.5 to 0.95 cm, and in width from 0.15 to 0.20 cm. The elytra of some specimens were pale with a few spots of pigmentation and a fringe of short papillae on the margin. Specimens from the Mexican Caribbean had a small dark spot near the elytrophore and a whitish spot over the elytrophore area ( Fig. 1 A). Nephridial papillae were elongated in ovigerous specimens or when the oocytes were recently released but some oocytes still remained. Distal papillae were sometimes also present over the anterodorsal surface of the neuropodia. Most of the specimens from the Mexican Caribbean were small, but many of them were ovigerous. In those specimens, the oocytes were abundant from segments 11 to 23 and were found in the parapodia ( Fig. 1 C) as well as the coelomic cavity. The oocytes ranged between 40 Μm and 50 Μm in diameter.

One specimen had large oocytes inside the parapodia; these oocytes ranged between 70 Μm and 120 Μm in diameter.

Barcode. Nucleotide sequences between 525-658 bp of the section of COI gene used for barcoding were obtained from five specimens, two from the Gulf of Mexico (ECOSUR-OH-P536, ECOSUR-OH-P567), and three from the Mexican Caribbean (ECOSUR-OH-P0257, ECOSUR-OH-P0258, ECOSUR-OH-P0261). The average evolutionary divergence over the five sequence pairs was 0.6%.

Discussion. The following features were described by Pettibone (1977) and were also observed in the additional material examined, but were not observed in the type material due to the poor condition: style of median antenna smooth, with subterminal expansion and filiform tip; lateral antennae shorter than median antenna and tentacular cirri similar to antennae.

Pettibone (1977) examined specimens from different regions, from North Carolina to Venezuela and from Baja California, Mexico, to Panama and Peru. She described and drew in a detailed manner the elytral tubercles of the syntypes; however, she did not indicate any differences with specimens from the Pacific region. The specimens from the Mexican Pacific actually have several features that differentiate them from L. humilis ; these are described below as a new species from the Grand Caribbean and are therefore described as new species. Type locality. Dry Tortugas, Florida and Kingston, Jamaica.

Distribution. Grand Caribbean.

Figures

FIGURE 1. Lepidonopsis humilis (Augener, 1922). A, complete, dorsal view; B, anterior end, dorsal view, arrow shows lobes of segment two; C, parapodium from median segment; D, papillae at distal margin of neuropodia. Abbreviations: ds, dark spot; ws, whitish spot. A, C – D specimen ECOSUR-P 1387. B ECOSUR-P 1376. Scale: A, 0.5 mm; B, 0.3 mm; C, 0.3 mm; D, 0.15 mm.

FIGURE 2. Lepidonopsis humilis (Augener, 1922). Syntype ZMB 6262. A, macrotubercles, first elytron; B, microtubercles of margin, first elytron; C, parapodium from median segment, posterior view (dorsal cirrus missing); D, papillae of neuropodium; E, notochaeta; F, bidentate neurochaetae. Abbreviations: p, marginal papillae. Scale bars: A, 30 µm; B – D, 12.5 µm; C, E, 25 µm; F, 60 µm.

FIGURE 3. Lepidonopsis humilis (Augener, 1922). A, first elytron; B, second elytron; C, third elytron; D, elytron from median segment; E, macrotubercles, first elytron; F, bidentate neurochaetae. A – E, specimen ECOSUR-P 1376. F, specimen ECOSUR- P 1387. Scale bars: A, 0.207 mm; B, 0.166 mm; C, 0.117 mm; D, 0.159 mm; E, 20 µm; F, 15 µm.