Halosydna parva Kinberg, 1856

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 : 1212-1215

Halosydna parva Kinberg, 1856

( Figures 17 , 18 )

Halosydna parva Kinberg, 1856 , 385; 1858: 17–18; 1910: 17–18, plate 5 figure 24; Seidler, 1924: 116; Hartman, 1939a, 33, plate 21, figure 265–267 (partim); Hartman 1949, 18–19, plate 1, figures 5–9 (partim); Salazar-Silva, 2006: 148.

Type material

Lectotype ( SMNH 402 ), Chincha Island , Peru, Leg Eugenie Expedition 1851, station 531, February to March, 1852, id. J. Kinberg.

Additional material

Ecuador: one specimen ( LACM-AHF POLY 2431 ), La Plata Island, Galapagos, 1 ◦ 16 ′ S, 81 ◦ 05 ′ 10 ′′ W, R / V Velero III, station 22-33, shore, 22 January 1933, coll. Allan Hancock Foundation. id. O. Hartman. One specimen ( LACM-AHF POLY 2434 ), Tagus Cove, Albemarle Island Galapagos, 0 ◦ 16 ′ 08 ′′ S, 91 ◦ 22 ′ 44 ′′ W, shallow water, coral, R / V Velero III, station 152-34, 14 January 1934, id. O. Hartman . Peru: One specimen ( LACM-AHF POLY 2432 ), off Viejas Island, Independencia Bay , 14 ◦ 15 ′ 05 ′′ S, 76 ◦ 12 ′ W, R / V Velero III, st. 374-35, 12 fm, sand and mud, 12 January 1935, coll. Allan Hancock Foundation, id. O. Hartman. One specimen ( LACM- AHF POLY 2433 ), Independencia Bay , 14 ◦ 14 ′ 08 ′′ S, 76 ◦ 08 ′ 30 ′′ W, R / V Velero III, station 380-35, shore, rock, 14 January 1935, coll. Allan Hancock Foundation, id. O. Hartman .

Description

Lectotype complete but in poor condition. Body with 36 segments, pigmentation absent. Prostomium bilobed, without cephalic peaks, laterally rounded, wider than long, slightly retracted into second segment ( Figures 17A , 18A ); facial tubercle not examined; two pairs of eyes, both on posterior half of prostomium; median antenna with ceratophore inserted frontally on prostomial lobes, style missing; lateral antennae with ceratophores inserted terminally as prolongations of prostomium lobes, at same level of median antenna ceratophore, style missing. Palps missing. Pharynx partially everted with stout jaws.

Tentacular segment not visible dorsally; tentaculophores with chaetae; tentacular cirri subdistally expanded, with short, filiform tips. Segment 2 not projecting over prostomium. First pair of elytrophores lateral to prostomium.

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. First pair of elytra with thick marginal papillae ( Figure 17B ); surfaces with conical microtubercles sclerotized ( Figure 17C,D ). Second and third pairs of elytra with microtubercles sclerotized and some macrotubercles distally rounded. Elytra in mid-body oval ( Figure 18B,C ), marginal papillae scarce ( Figure 18D ), surfaces with macrotubercles sclerotized, distally rounded ( Figure 18E ), microtubercles abundant ( Figure 18F,G ). Elytra in posterior segments without marginal papillae, surfaces with microtubercles and macrotubercles of similar shape to those in anterior elytra.

Notopodia shorter than neuropodia. Neuropodia distally truncate, prechaetal lobe with small rounded lobe near acicular tip. Dorsal cirri missing; cirrophores basally expanded. Elytrophores wider than dorsal tubercles. Ventral cirri taper to filiform tips. Anus dorsal. Pygidium thick with anal cirri missing.

Notochaetae with rows of spines; the smaller curved with blunt tips ( Figure 17E ); remaining ones slender tapering to capillary tips. Neurochaetae, with lateral rows of spines on upper region; bidentate tips, subdistal tooth smaller than main tooth ( Figure 17F ).

Remarks

The type material is labelled as holotype, but the species was originally described from several specimens. This specimen should be considered a syntype. However, it was redescribed by Hartman (1949) so herein it is being designated as Lectotype.

The species was reported from Bahía Santa Rosalia, Baja California Sur, Mexico ( Hartman 1939a). However, Salazar-Silva (2006) examined the specimen and corresponds to H. leius . Hence, H. parva does not occur in the Mexican Pacific.

The non-type material ranged from 1.2 cm long and 0.3 cm wide, to 3.1 cm long and 0.55 cm wide, and shows a short rounded lobe projecting over the prostomium on segment 2, eyes round dark, antennae similar in shape to tentacular cirri and papillate palps.

The type material of Halosydna virgini Kinberg, 1856 , has been re-examined. Contrary to Hartman (1949), the species is considered as valid and so it is redescribed below.

Type locality

Peru, Chincha Island.

Distribution

Ecuador (la Plata Island; Tagus cove Island, Galapagos), Peru (Chicha Island, Independencia Bay).

Figures

Figure 17. Halosydna parva Kinberg, 1856. Holotype SMNH 402. (A) Anterior end, dorsal view; (B) first elytron fringe; (C, D) first elytron, microtubercles; (E) notochaetae; (F) bidentate neurochaeta.

Figure 18. Halosydna parva Kinberg, 1856. Holotype SMNH 402. (A) Anterior end, dorsal view; (B) left elytron from middle segment; (C) right elytron from middle segment; (D) same, fringe; (E) same, macrotubercles; (F, G) microtubercles.