Corresponding authors: María Ana Ana Tovar-Hernández (
Academic editor: Sarah Faulwetter
The sabellid genera
The sabellid genus
Seven species of
In this study,
Major differences amongst
The present definition primarily follows
Figures 1–5
Base of the radiolar crown smooth (basal lamina) with prominent, erect, dorsal and ventral flanges. Collar chaetae arranged in a bunch. Ocelli in both sides of the outer margin of radioles. Dorsal-most radioles with ocelli in groups of 15–22 (basal ocelli distributed in two rows, distal ocelli forms only one row). Ventral radioles with 5–10 ocelli in a single row. Simultaneous hermaphrodite.
Ripe simultaneous hermaphrodites were found with female and male gametes within the coelom of abdominal segments and also attached to the internal tube layer (Fig.
According to
In addition, it should be noted that the spelling of the species name
Detailed information about eye and ocelli types found in
Reproductive information is absent for
Most of the sabellid species present a thorax consisting typically of eight chaetigers (
Perhaps the presence of a long thorax in
Radioles in semi-circular radiolar lobes, each radiole with at least four rows of vacuolated cells. Radiolar crown with elongate basal lobes; palmate membrane, radiolar flanges and dorsal and ventral basal flanges present. Numerous ocelli arranged in longitudinal rows on lateral sides of radioles. Dorsal lips with radiolar appendages, pinnular appendages absent; ventral radiolar appendages absent. Ventral lips and parallel lamellae present, ventral sacs inside radiolar crown. Anterior peristomial ring low, of even height, or high and rounded. Posterior peristomial ring collar with narrow mid-dorsal gap, dorsal margins laterally fused to the faecal groove, ventrally entire or with mid-ventral incision and short ventral lappets. Peristomial vascular loops absent. Peristomial eyespots absent. Thorax and abdomen with variable number of segments. Glandular ridge on chaetiger 2 absent. Ventral shields present. Interramal eyespots may be present. Collar chaetae spine-like, arranged in distally oblique longitudinal rows, diagonal, J or C-inverted shaped; superior thoracic notochaetae short spine-like, inferior thoracic notochaetae paleate. Thoracic uncini avicular, with several rows of minute and similar in size teeth above main fang, developed breast and medium-sized handle; neuropodial companion chaetae with strongly asymmetrical hood, stouter on one margin and thin, elongate tip. Abdominal uncini similar to the thoracic ones. Anterior abdomen with a superior group of elongate, narrowly-hooded chaetae and an inferior group of paleate chaetae with mucros. Posterior abdomen with modified, elongate, narrowly-hooded chaetae and paleate chaetae (spherical or oval) with long mucros. Pygidial eyespots may be present. Anal cirrus absent (after
The generic diagnosis by
As
Chaetae from the collar have been called spine-like
Variability of some other features were emphasised by
As stated by
Figures 6–9 and 10A–F
Ventral margin of collar incised, forming rounded lappets. Short bands of radiolar ocelli (each band as long as the space of 4–6 pinnules), ocelli distributed in single rows of five ocelli (in smallest, juvenile specimen) to 16 ocelli ocelli (largest, ripe specimens), bands located at three quarters of the radiolar crown length (Table
Females with oocytes in anterior abdomen and males with spermatozoa along abdomen (UANL 8135) with spherical nucleus and rounded cap-like acrosome.
Fouling specimens here reviewed from the Gulf of California match with descriptions of the holotype provided by
Data available for species of
Figures 10G–N and 11–15
Ventral margin of collar entire. Short bands of radiolar ocelli (each band as long as the space of seven pinnules), ocelli distributed in oval groups of 26–30 ocelli each, groups located at the middle of the radiolar crown length.
The name is a compound adjective, where the first term refers to the black colour of the worm (Latin
In La Paz (Gulf of California),
Holotype (UANL 8138) and paratypes (UANL 8139, 8140) males with a huge mass of sperm in abdomen. Ripe worms have abdomen pyriform in cross section with a dorsal hump full of sperm. Males from additional samples (UANL 8141) have sperm between the body wall and internal layer of tubes. Spermatozoa has a spherical nucleus and rounded cap-like acrosome. Paratype female (UANL 8140) has full-developed oocytes in abdomen.
In his revision of
Specimens here reviewed from the Gulf of California, match only with the specimens reported from Zihuatanejo (western Mexico) by
Amongst other species of
Figures 10O–S, 16–18
Ventral margin of collar incised, forming rounded lappets. Long bands or radiolar ocelli (each band as long as the space of 13 pinnules), ocelli distributed in single rows of 24 ocelli each, bands located at the middle of the radiolar crown length. Interramal eyespots on abdominal segments.
The specific epithet
Holotype female with fully-developed oocytes in abdomen. Paratype male with sperm in abdomen, spermatozoa with spherical nucleus and rounded cap-like acrosome (Fig.
Abdominal interramal eyespots have been only reported in
Amongst the species of
This study provides some new morphological characters and reproductive issues for the species of
Four species of
Thanks are given to Luis F. Carrera-Parra, Isabel Molina, Sergio I. Salazar-Vallejo and Tulio F. Villalobos-Guerrero (ECOSUR-Chetumal, México), who collected and sent us specimens from Veracruz and Acapulco to their study. Special thanks to Humberto Bahena (ECOSUR-Chetumal, México) for sharing pictures contained in Figures 1, 6–7,and 10. Guadalupe Nieto (ECOSUR-Tapachula) processed SEM photographs included in Figure 5. Beatriz Yáñez-Rivera (CIAD-Mazatlán), Tulio Villalobos-Guerrero (Kagoshima University), Jose María Aguilar-Camacho (Hebrew University of Jerusalem), Irving Ramírez-Santana (Campamento Tortuguero Nuevo Vallarta) and José Salgado-Barragán (ICML-UNAM, Mazatlán) were all of great help during sampling in marinas and ports of the Gulf of California and sorting of materials. Anna Murray (Australian Museum) and Maria Capa (Universidad de las Islas Baleares) provided valuable suggestions of
Selected features of
Selected features of
Selected features of
Chaetae of
Alive specimens of
Alive specimens of
Selected features of
Selected features of
Chaetae and uncini of species in
Alive holotype of
Selected features of
Selected features of
Selected features of
Chaetae of
Selected features of
Selected features of
Chaetae of
Comparison of the genera
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Palmate membrane | Present | Present | Present |
Radiolar flanges | Absent | Present | Present |
Radiolar ocelli | Present | Present | Present |
Dorsal pinnular appendages | Present | Absent | Absent |
Dorsal lips with radiolar appendages | Present | Present | Present |
Ventral lips | Present | Present | Present |
Paralel lamellae | Present | Present | Present |
Ventral sacs | Present | Present | Present |
Peristomial eyes | Absent | ? | Absent |
Anterior margin of anterior peristomial ring | High, triangular, ventrally longer (present study) |
Low, of even height all around ( |
Low, of even height all around ( |
Flanges on base of radiolar crown | Present, dorsal and ventrally, erect, prominent | Absent | Present, dorsal and ventrally, less developed than |
Accessory lamellae | Absent | Present, dorsal pair curved, rounded distally; ventral pair collar-like | Absent |
Arrangement of chaetae in collar fascicle | In a bunch | In a bunch | Longitudinal, oblique, L-shaped, J-shaped, C-shaped |
Number of thoracic chaetigers | 20 to 73 (usually near 50) | 9–13 ( |
Usually 8, but |
Thoracic tori | Contacting ventral shields | Not contacting ventral shields | Contacting ventral shields |
Mucro of thoracic paleate chaetae | Absent | Absent or present | Absent or reminiscent |
Abdominal chaetae | |||
Reproduction | Simultaneous hermaphroditism | ? | Gonochorism |
Comparison of
Species | |||
Record or type locality | Topolobampo, Sinaloa; Bahía Concepción, Baja California Sur, Gulf of California (Record) | La Paz, Baja California Sur, Gulf of California (type locality) | Acapulco, Guerrero, western Mexico (type locality) |
Ventral margin of collar | Incised | Entire | Incised |
Lateral margin of collar | Even in height | Even in height or rarely V-shaped | Even in height |
Radiolar ocelli | 5–6 ocelli in single row in smallest specimens, 14–15 ocelli in largest specimen | 26–30 ocelli in oval group | 24 ocelli in single rows |
Length of bands or groups of ocelli | As long as space of 4–6 pinnules | As long as space of eight pinnules | As long as space of 13 pinnules |
Base of radiolar crown (basa lamina) | Short (as long as three segments) | Short to medium length (as short as 3, 4 or 5 thoracic segments) | Short (as long as three thoracic segments) |
Interramal eyespots on abdominal segments | Absent | Absent | Present |
Location of ocelli | 3/4 of the radiolar crown length | 1/2 of the radiolar crown length | 1/2 of the radiolar crown length |
Extension of palmate membrane | Basal half of the radiolar crown length (1/2) | Basal half of the radiolar crown length (1/2) | Basal half of the radiolar crown length (1/2) |
Chaetiger 1 | Straight, oblique | Straight, oblique or slightly curved basally | Straight, oblique |
Abdominal paleae | Anterior abdominal segments: spherical with short mucros. |
Anterior abdominal segments: spherical with short mucros. |
Anterior abdominal segments: spherical with short mucros. |