Halosydna riojaenriquei, Salazar-Silva, 2013

Salazar-Silva, Patricia, 2013, Revision of Halosydna Kinberg, 1856 (Annelida: Polychaeta: Polynoidae) from the Tropical Eastern Pacific and Grand Caribbean with descriptions of new species, Journal of Natural History 47 (17 - 18), pp. 1177-1242 : 1232-1240

publication ID	https://doi.org/ 10.1080/00222933.2012.752934
persistent identifier	https://treatment.plazi.org/id/2D304A56-FFA4-F52E-37FA-FA09FBE4FBEE
treatment provided by	Felipe
scientific name	Halosydna riojaenriquei
status	sp. nov.

Treatment

Halosydna riojaenriquei View in CoL sp. nov.

( Figures 30 View Figure 30 , 31 View Figure 31 )

Type material

Holotype ( ECOSUR 0134 View Materials ). Playa los pinos, Mazatlán, Mexico, in front of Facimar, depth 4 m, on rock oyster, coll. M. Tovar and P. Salazar, 27 February 2004 . Paratypes: Four specimens ( ECOSUR 0135 View Materials ) of Playa los Pinos , Mazatlan, Mexico, station in front of Facimar, depth 4 m, on rock oyster, coll. M. Tovar and P. Salazar, 27 February 2004 . One specimen ( ECOSUR 0136 View Materials ), Playa los pinos, Mazatlán, Mexico, in front of Facimar, depth 4 m, on rock oyster, coll. M. Tovar and P. Salazar, 27 February 2004 . One specimen ( ECOSUR 0137 View Materials ), Playa los Pinos , Mazatlán, Mexico, in front of Facimar, depth 4 m, on rock oyster, coll. M. Tovar and P. Salazar, 27 February 2004 .

Additional material

Mazatlan, Mexico, Pacific Ocean: Two specimens ( ECOSUR P02580), off Playa los Pinos, Mazatlan, station Cañon, coll. M. Tovar and P. Salazar, 22 February 2004. Two specimens ( ECOSUR P02581), Playa los Pinos, Mazatlan, Station Cañon, coll. M. Tovar and P. Salazar, 22 February 2004. One specimen ( ECOSUR P02582), Playa los Pinos, Mazatlán, near Marine Biology School, on rock oyster, coll. M. Tovar and P. Salazar, 23 February 2004. One specimen ( ECOSUR P02583), Playa los Pinos, Mazatlan, near Marine Biology School, coll. M. Tovar and P. Salazar, 27 February 2004, Two specimens ( ECOSUR P02584), playa los Pinos, Mazatlan, near Marine Biology School, depth 4 m, on rock oyster, coll. M. Tovar and P. Salazar, 27 February 2004. One specimen ( ECOSUR P02585) of Playa los Pinos, Mazatlan, near Marine Biology School, depth 4 m, on rock oyster, coll. M. Tovar and P. Salazar, 27 February 2004. One specimen ( ECOSUR P02586) of Playa los Pinos, Mazatlan, in front Marine Biology School, depth 4 m, on rock oyster, coll. M. Tovar and P. Salazar, 27 February 2004. Guerrero, Mexico Pacific Side. One specimen ( ECOSUR P02587) of La Quebrada, Acapulco, on Spondylus calcifer , coll. M. Tovar and P. Salazar, 25 May 2000. One specimen ( ECOSUR P02588) of La Quebrada, Acapulco, on Spondylus , 15 m, coll. A. Medina, 25 May 2000. One specimen ( ECOSUR P02589) of La Quebrada, Acapulco, 25 May 2000, on Pinctada mazatlanica . coll. M. Medina. One specimen ( ECOSUR P0 2590) of Los Cantiles, Acapulco, coll. A. Medina, on Spondylus , 26 May 2000. One specimen ( ECOSUR P02591) of La Quebrada, Acapulco, on Muricanthus spondylus , 25 May 2000, coll. A Medina. One specimens ( ECOSUR P02592) of La Condesa, Acapulco, coll. A. Medina, 27 November 1999, Three specimens ( ECOSUR P02593) of La Quebrada, Acapulco, 6 m depth, coll. A. Medina, on Spondylu calcifer , 25 May 2000. One specimen ( ECOSUR P02594) of La Quebrada, Acapulco, coll. A. Medina, 25 May 2000. One specimen ( ECOSUR P02595) of La Roqueta, Acapulco, on sponge, coll. A. Medina, 26 May 2000. Five specimens ( ECOSUR P02596) of Los Cantiles, la Quebrada, Acapulco, on Spondylus coll. A. Medina, 26 May 2000. One specimen ( ECOSUR P02597) of Los Cantiles, la Quebrada, Acapulco, on Spondylus , coll. A. Medina, depth 8 m, 26 May 2000. One specimen ( ECOSUR P02598) of Los Cantiles, la Quebrada, Acapulco, on Spondylus , coll. A. Medina, 26 May 2000. One specimen ( ECOSUR P02599) of Los Cantiles, Acapulco, on Spondylus , depth 8 m, coll. A. Medina, 26 May 2000. One specimen ( ECOSUR P02600) of La Quebrada, Acapulco, 6 m, coll. A. Medina, on Pinctada , 25 May 2000. Oaxaca, Mexico Pacific Side. One specimen ( ECOSUR P02601) of Puerto de Abrigo, Huatulco, on Spondylus , 22 May 2000. One specimen ( ECOSUR P02602) of Puerto de Abrigo, Huatulco, 22 May 2000. Four specimens ( ECOSUR P02603) la Entrega, Huatulco, 3 m, on coral rock, 23 May 2000. Two specimens ( ECOSUR P02604) of La Entrega, Huatulco, 3 m, on stromatolite, 23 May 2000. One specimen ( ECOSUR P02605) of La Entrega, Huatulco, Transect 1, coll. P. Gomez 1991. One specimen ( ECOSUR P0 2606) of Puerto de Abrigo, Huatulco, 22 May 2000.

Etymology

This species is named for Enrique Rioja in recognition of his studies of polychaetes from Mexico.

Description

Holotype with 36 segments, 1.05 cm long and 0.25 cm wide. Body pale yellow, dorsum with a band of green pigment on each segment. Brownish pigment on ceratophores and on antennae.

Prostomium elongate with dots of pigment dorsally; facial tubercle long, rounded, with dark pigment; two pairs of dark eyes, anterior pair dorsolateral on widest part of prostomium, posterior pair near posterior margin; median antenna with ceratophore inserted frontally on prostomial lobes, style subdistally expanded with dark pigment, tip filiform, lateral antennae with ceratophores inserted terminally as prolongations of prostomium lobes, styles similar to median antenna. Palps robust, surfaces with papillae, distally tapering to filiform tips. Pharynx everted, with nine pairs of papillae, two pairs of jaws not fused to each other medially.

Tentacular segment not visible dorsally. Tentaculophores with chaetae. Tentacular cirri similar to median antenna. Segment 2 projecting slightly over prostomium as small nuchal lobe, two small tubercles dorsally.

Body with 18 pairs of elytra on segments 2, 4, 5, 7, 9, 11, then alternate to 21, 23, 25, 27, 28, 30, 31, 33. Three posteriormost segments with dorsal cirri. Elytra overlapping mid-dorsally, with spots of olive green towards the dorsal midline, without pigmentation over elytrophores. First pair of elytra circular, without marginal papillae ( Figure 30A View Figure 30 ); surfaces smooth except for small micropapillae and sclerotized, conical microtubercles ( Figure 30B View Figure 30 ), scattered, larger near elytrophore ( Figure 30A View Figure 30 ). Second pair of elytra with granular surfaces ( Figure 30C View Figure 30 ) due to presence of abundant microtubercles, conical-truncate, short ( Figure 30D,E View Figure 30 ). Elytra in median and posterior segments ( Figure 30F View Figure 30 ) without marginal papillae, surfaces with tiny micropapillae ( Figure 30G View Figure 30 ) and microtubercles near margins.

Notopodia shorter than neuropodia ( Figure 30H View Figure 30 ). Neuropodia distally truncate, prechaetal lobe with small rounded lobe near acicula tip. Elytrophores wider than dorsal tubercles. Dorsal cirri subdistally expanded, pigmented, tapering to filiform tips. Cirrophores basally, expanded. Ventral cirri tapering to filiform tips. Nephridial papillae visible from segment 11, increasing in size toward posterior segments. Anus dorsal. Pygidium with anal cirri missing.

Notochaetae shorter than neurochaetae, with rows of spines, the smaller curved, blunt tips, the remaining ones slender, tapering to long capillary tip. Neurochaetae with rows of spines on upper region, tip bidentate, subdistal tooth well developed. On first parapodia the neurochaetae have entire tips.

Remarks

Most specimens of Halosydna riojaenriquei sp. nov. have olive-green elytra, but some have the pigment concentrated medially or covering the entire surface. Other specimens have yellow-brown pigment and all elytrophore scars are unpigmented. The prostomium can be unpigmented or with small black spots. The features of the paratypes ( Figure 31A–D View Figure 31 ) are consistent with those of the holotype, the largest specimen is 2 cm long.

Halosydna riojaenriquei sp. nov. resembles H. hartmanae ( Kudenov, 1975) from Sonora, in lacking marginal papillae, but the former has anteriormost elytra with abundant microtubercles scattered over the entire surface and median and posterior elytra with microtubercles around posterior borders, while H. hartmanae has median and posterior elytra with microtubercles forming patchs on the anterior half.

Type locality

Playa los Pinos, Mazatlan, Mexico.

Distribution

Mexico, Pacific Ocean: Mazatlan, Guerrero, Oaxaca .

Key to species of Halosydna Kinberg, 1856 , of eastern Pacific, Grand Caribbean and other worldwide localities (species marked with an asterisk)

1. Neurochaetae with tips entire ( Figure 9E View Figure 9 )................................ 2 Neurochaetae with tips bidentate ( Figure 3C View Figure 3 )............................. 5

2. Elytra thick, fleshy; elytra of anterior segments without macrotubercles; elytra of the mid-body and posterior segments with macrotubercles disc-shape short ( Figure 10F View Figure 10 )................................... H. latior Chambelin, 1919a Elytra View in CoL fragile; elytra of anterior segments with macrotubercles; elytra of middle and posterior segments without macrotubercles.................... 3

3. Macrotubercles of anterior elytra of two types, some blunt and others conical thick ( Figure 21B View Figure 21 )....................... H. tuberculifer Chamberlin, 1919a Macrotubercles View in CoL of anterior elytra of one type, conical..................... 4

4. Macrotubercles of anterior elytra conical-slender, abundant, scattered on all elytral surface ( Figure 14C View Figure 14 )...................... H. nebulosa View in CoL (Grube, 176) ∗ Macrotubercles of anterior elytra conical-thick, most prominent over the scar of the elytrophore ( Figure 1D View Figure 1 )................. H. brevisetosa Kinberg, 1856 View in CoL

5. Elytra with fringe of marginal papillae.................................... 6 Elytra without fringe of marginal papillae............................... 12

6. Elytra with vesicular tubercles, not sclerotized............................ 7 Elytra without vesicular tubercles........................................ 9

7. Macrotubercles from first pair of elytra vesicular, not sclerotized, ovoid, prominent and long ( Figure 27A View Figure 27 ); sclerotized tubercles absent............................................................... H. salazarvallejoi View in CoL sp. nov. Macrotubercles from first pair of elytra vesicular, hemispherical, no prominent, short; tubercles sclerotized present.................................. 8

8. Fringe of marginal papillae on all elytra; first pair of elytra with macrotubercles long, sclerotized conical-truncated ( Figure 11B View Figure 11 ); on posterior elytra vesicular macrotubercles scarce.......... H. leius ( Chamberlin, 1919a) Fringe View in CoL of marginal papillae only on anterior elytra; first pair of elytra with vesicular macrotubercles long, not sclerotized ( Figure 24D View Figure 24 ), on posterior elytra the vesicular macrotubercles are abundant........... H. olgae View in CoL sp. nov.

9. Elytra of anterior segments with tubercles sclerotized short and long...... 10 Elytra of anterior segments with tubercles sclerotized short............... 11

10. Elytra of anterior segments with macrotubercles distally rounded, short ( Figure 18B View Figure 18 )....................................... H. parva Kinberg, 1856 Elytra View in CoL of anterior segments with macrotubercles conical, long ( Figure 19B View Figure 19 )............................................. H. patagonica Kinberg, 1856 View in CoL ∗

11. Elytra of anterior segments with macrotubercles conical ( Figure 7C View Figure 7 )...................................................... H. johnsoni ( Darboux, 1899) Elytra View in CoL of anterior segments with microtubercles conical-truncated ( Figure 23C View Figure 23 ).............................. H. virgini Virgini Kinberg, 1856 View in CoL ∗

12. Elytra with vesicular tubercles.......................................... 13 Elytra without vesicular tubercles....................................... 14

13. First pair of elytra without microtubercles sclerotized; with vesicular macrotubercles ovoid ( Figure 28A View Figure 28 ), abundant; elytra of middle and posterior segments with macrotubercles soft, ovoids long....... H. silvamariae View in CoL sp. nov. First pair of elytra with microtubercles sclerotized ( Figure 13D View Figure 13 ), macrotubercles hemispheric, short, scarce; elytra of middle and posterior segments with vesicular microtubercles hemispherical.................................................................. H. leucohyba ( Schmarda, 1861)

14. Elytra with macrotubercles............................................. 15 Elytra without macrotubercles.......................................... 16

15. Macrotubercles of elytra of anterior segments abundant, conical long and ovoid, surface wrinkled ( Figure 4E View Figure 4 ).............. H. glabra Hartman, 1939a Macrotubercles View in CoL on elytra of anterior segments scattered conical short blunt, surface smooth ( Figure 2C View Figure 2 )............... H. fuscomarmorata ( Grube, 1876) View in CoL

16. Elytra of middle and posterior segments with microtubercles forming a patch on anterior part of the elytra ( Figure 6B View Figure 6 )..... H. hartmanae ( Kudenov, 1975) Elytra View in CoL of middle and posterior segments with microtubercles over the half posterior elytral surface................................................. 17

17. Microtubercles abundant, scattered over the half posterior elytral surface ( Figure 16B View Figure 16 ).............................. H. nesiotes ( Chamberlin, 1919b) Microtubercles View in CoL scarce, around of posterior margin... H. riojaenriquei View in CoL sp. nov.

Conclusion

The genus Halosydna belongs to the group of polynoids with a constant number of segments and elytra, and a relatively short but not fragile body. Halosydna leucohyba is the only species occurring in the Grand Caribbean region but has also been reported for the Mexican Caribbean. The genus is clearly more diverse in the tropical eastern Pacific than in the Grand Caribbean. This pattern of diversity might be caused by a higher diversity of habitats in the tropical eastern Pacific, as reported for other groups ( Muss et al. 2001). However, both regions require more taxonomic studies to increase records of Halosydna species in less-studied localities.

Halosydna species are geographically distributed both in cold and warm waters. The species of the tropical eastern Pacific and Grand Caribbean species have neurochaetae with bidentate tips, and those of north and south Pacific coasts have neurochaetae with entire tips. This pattern might be related to the predominant modes of life as epibionts in the former and commensals in the latter. Martin and Britayev (1998) noted that members of commensal species tend to have less elaborate chaetae.