Pherusa neopapillata Hartman, 1961

Salazar-Vallejo, Sergio I., 2014, Revision of Pherusa Oken, 1807 (Polychaeta: Flabelligeridae), Zootaxa 3886 (1), pp. 1-61 : 27-29

Pherusa neopapillata Hartman, 1961

Figure 9

Pherusa neopapillata Hartman 1961:121–122 , Pl. 25, Figs 1–2 , Pl. 26, Figs 1–7 , 1969:301–302, Figs 1–5 .— Blake, 2000:17–18, Fig. 1.7 .

Type material. Northeastern Pacific Ocean, California. Holotype ( LACM 531 ) and paratypes ( LACM 532 ), off south side of San Nicolas Island , California, RV Velero IV, Sta. 1205 (33°12'45" N, 119°29'15" W à 33°12'40" N, 119°29'40" W), 37–42 m, 24 Nov. 1940 (paratypes 8 anterior fragments and 7 medial or posterior fragments; larger anterior fragment partly dehydrated, cylindrical, posteriorly tapered).

Additional material. USA, Alaska. One specimen ( CAS 162028 ), Marine Taxonomic Services, Sta. GB 1, 15 Oct. 1995, no further data (36 mm long, 5 mm wide, cephalic cage 13 mm long, 36 chaetigers) . California. Many specimens ( LACM 4943 ), RV Velero IV, Sta. 5541 (33º43'12" N, 118º20'45" W), 22 m, coarse black sand, 19 Dec. 1957 (complete ones 10.0– 23.5 mm long, 1.0– 2.5 mm wide, cephalic cage 3.5–5.0 mm long, 49–92 chaetigers) .

Western Mexico. One specimen ( LACM 4940 ), broken in two, RV Velero III, Sta. 1260 (27º49'32" N, 115º06'40" W à 27º54'15" N, 115º07'00" W), Dewey Channel, opposite San Eugenio Point, 38–44 m, coralline rocks, 27 Feb. 1941 (16 mm long, 2 mm wide, cephalic cage 4 mm long, 37 chaetigers) .

Description. Holotype (LACM 531) damaged; 31 mm long, 3.3 mm wide, cephalic cage 5 mm long, 25 chaetigers ( Fig. 9A ). Body papillae filiform, capitate, thick, carrying sand grains dorsally along anterior chaetigers ( Fig. 9B ), and finer sediment grains in medial (and posterior chaetigers). Papillae few on anterior chaetigers, larger, becoming shorter and more abundant on medial chaetigers, and arranged in up to 10 transverse series per segment.

Cephalic hood not exposed. Prostomium low cone; eyes and caruncle not seen (CAS 162028) with four large black eyes; caruncle short triangular. Palps thick, contracted; palp keels low, rounded; lips distorted by contraction.

Branchiae cirriform, arranged as two concentric rows, 4 filaments in a continuous row, and other four filaments separated into two lateral groups, each with two filaments, all of about the same length and width, longer than palps. Nephridial lobes not seen; one specimen (CAS 162028) with nephridial lobes rising from inner side of anterior row inner branchiae, basally widened, tapered distally.

Cephalic cage chaetae about twice as long as body width. Chaetigers 1–3 forming cephalic cage, chaetae decreasing in size from first chaetiger; arranged in short lateral series, about 6–8 per fascicle (damaged).

Anterior dorsal margin of first chaetiger with a medial lobe, with distal papillae. Anterior chaetigers with longer papillae dorsally, not associated with notopodial lobes. Chaetigers 1–3 of about the same length. Chaetal transition from cephalic cage to body chaetae abrupt; anchylosed, falcate blunt neurohooks from chaetiger 4. Gonopodial lobes reduced to oval smooth areas in chaetigers 5–6.

Parapodia poorly developed; chaetae emerge from body wall. Parapodia lateral; medial neuropodia ventrolateral. Notopodia and neuropodia without long papillae; close to each other.

Medial notochaetae arranged in transverse series; all multiarticulated capillaries (as in a fan), articles short basally, long medially and distally ( Fig. 9C ), about 6–8 per fascicle, as long as ¼ body width. Neurochaetae multiarticulated capillaries in chaetigers 1–3; neurohooks from chaetiger 4, arranged in transverse series, falcate anteriorly ( Fig. 9D ), more straight posteriorly ( Fig. 9E ), 4 hooks per fascicle to the end of the fragment.

Posterior end (observed in non-type specimens) tapered into a blunt cone, anus terminal, without anal cirri. Variation. Specimens showed a large variation in several morphological features as follows.

Some specimens had reddish chaetae whereas type lot and other specimens have paler or straw-colour chaetae. On the other hand, even the smaller paratype (1 mm body width, cephalic cage 2 mm long), had simple falcate neurohooks in chaetiger 4. A posterior fragment with 27 chaetigers has 3 neurohooks per fascicle.

Remarks. Pherusa neopapillata Hartman, 1961 belongs in the group of species with sand particles on their dorsal body papillae; this group includes P. andersonorum n. sp., P. aspera ( Stimpson, 1854) , Pherusa incrustata Quatrefages, 1866 , reinstated, and P. obscura Quatrefages, 1849 reinst. As stated above, P. andersonorum n.sp. and P. aspera have sediment particles throughout the body instead of having them restricted to anterior or to anterior to medial segments. Pherusa neopapillata is most similar to P. incrustata because they both have 7–10 transverse rows of papillae per segment, but they differ in the abundance of cephalic cage chaetae and on the extension of sand particles along the body. In P. neopapillata the cephalic cage has 6–8 chaetae per fascicle, and sand particles are restricted to anterior segments, whereas in P. incrustata cephalic cage chaetae are more abundant (10–14 notochaetae, 6–8 neurochaetae per bundle), and there are sand particles in papillae of anterior and medial segments.

The original description included illustrations of larger, complete specimens (40–45 mm long, 43–45 chaetigers) but they were not found. Later works on Californian flabelligerids mix names with specific features; P. neopapillata is the species regarded as having many abundant, short papillae, and P. papillata is the one with larger, less abundant papillae. These features, in fact, correspond to the other species as shown by the revision of the type material. The difference in branchial numbers previously indicated by Hartman (1961) cannot be confirmed; perhaps due to the poor state of the paratypes. The specimen from Alaska (CAS 162028) have sand particles or each papilla forms a large tubercle with fine sediment; these features are not observed in the Californian specimens, perhaps due to their preservation conditions.

Distribution. Alaska to Southern California, in subtidal shallow depths (22–44 m depth).

Figures

FIGURE 1. Pherusa plumosa (Müller, 1776). A. Neotype (USNM 23257), complete specimen, dorsal view. B. Anterior end, dorsal view. C. Another specimen (USNM 8952), head, frontal view (branchiae and palps removed; BS: branchial scar, LL: lateral lip, PS: palp scar, VL: ventral lip). D. Neotype, anterior end, right side, ventral view. E. Same, chaetiger 9, notochaetae. F. Same, neurochaetae. Scale bars: A: 7.3 mm, B: 1.2 mm, C: 1 mm, D: 0.67 mm, E: 0.33 mm, F: 0.3 mm.

FIGURE 2. Pherusa affinis (Leidy, 1855), paraneotypes (USNM 1251742). A. Anterior end, dorsal view. B. Same, ventral view. C. Non-type specimen (USNM 40214), anterior end, oblique dorsal view. D. Same, head, frontal view (branchiae and palps removed; BS: branchial scar, LL: lateral lip, PS: palp scar). E. Another paraneotype (USNM1251742), chaetiger 10, right notopodium (insets: basal and medial chaetal regions). F. Same, chaetiger 21, right neuropodium (insets: neurochaetal tips). Scale bars: A: 0.80 mm, B: 0.76 mm, C: 1.2 mm, D: 0.70 mm, E: 110 µm, F: 100 µm.

FIGURE 3. Pherusa andersonorum n. sp. A. Holotype (LACM 2602), oblique lateral view. B. Same, anterior end, ventral view showing ventral pharyngeal organ. C. Paratype (LACM 2603), anterior end, dorsal view, methyl green staining. D. Same, head, partly everted (branchiae and palps removed; BS: branchial scar, NL: nephridial lobe, PS: palp scar). E. Another paratype with one palp and all branchiae preserved (Pa: palp, VPO: ventral pharyngeal organ). F. Another paratype, cross section of a medial segment. G. Same, chaetiger 5, right neurochaetae. H. Same, chaetiger 20, right neurochaetae. Scale bars: A: 2.7 mm, B: 0.9 mm, C: 1.1 mm, D: 0.3 mm, E: 0.7 mm, F: 0.25 mm, G: 50 µm, H: 46 µm.

FIGURE 4. Pherusa aspera (Stimpson, 1854). A. Neotype (USNM 8889), anterior region, dorsal view. B. Same, ventral view. C. Another specimen (USNM 8957), head, frontal view (branchiae and palps removed; BS: branchial scar, LL: lateral lip, PS: palp scar). D. Neotype, chaetiger 10, right notopodium (inset: chaetal tips). E. Same, chaetiger 9, neurochaetae (two smaller neurochaetae not shown). Scale bars: A, C: 0.7 mm, B: 0.9 mm, D: 225 µm, E: 112 µm.

FIGURE 5. Pherusa hobsonae n. sp. A. Holotype (USNM 43803), lateral view. B. Anterior end, dorsal view. C. Same, right side, ventral view. D. Paratype (USNM 1131565), anterior end, dorsal view, tunic removed. E. Same, head, frontal view (branchiae and palps removed; BS: branchial scar, NL: nephridial lobe, PS: palp scar). F. Paratype, chaetiger 12, right parapodium, notochaetae (inset: basal and distal regions). G. Same, chaetiger 12, right parapodium, neurochaetae (one not shown). Scale bars: A: 3 mm, B: 2.2 mm, C: 1.7 mm, D: 1 mm, E: 0.5 mm, F: 0.25 mm, G: 45 µm.

FIGURE 6. Pherusa incrustata de Quatrefages, 1866, reinstated. A. Syntype (MNHN 382), dorsal view (inset: posterior region of dried syntype with large dorsal sediment particles). B. Anterior end, dorsal view (body wall damaged by removal of sediment particles). C. Anterior end, ventral view. D. Non-type specimen (MNHN 507), anterior end, dorsal view. E. Another non-type specimen (MNHN 183), head, frontal view (branchiae and palps removed; BS: branchial scar, LL: lateral lip, PS: palp scar; *: nephridial lobes base). F. Syntype (MNHN 381), chaetiger 10, basal, medial and distal notochaetal regions. G. Same, chaetiger 10, neurochaetae (2 broken). Scale bars: A: 3 mm, B: 2 mm, C: 1.9 mm, D: 1.4 mm, E: 0.8 mm, F: 0.3 mm, G: 0.4 mm.

FIGURE 7. Pherusa mikacae n. sp. A. Holotype (NHMR 17740), anterior end, dorsal view. B. Paratype (NHMR 17741), anterior end exposed, ventral view (palps corrugated, branchiae smooth). C. Paratype (ECOSUR), anterior end, dorsal view. D. Same, ventral view. E. Same, anterior region, ventral view. F. Parapodium 12, notochaetae (inset: basal, medial and distal regions). G. Same, parapodium 12, neurochaetae with eroded tips (inset: paratype NHMR 17742, parapodium 10, tip of neurohook). Scale bars: A: 0.9 mm, B: 0.8 mm, C, E: 0.7 mm, D: 1.3 mm, F: 160 µm, G: 80 µm.

FIGURE 9. Pherusa neopapillata Hartman, 1961. A. Holotype (LACM 531), lateral view. B. Paratype (LACM 532), anterior end, dorsal view, some sand particles removed. C. Same, chaetiger 11, notochaetae. D. Same, chaetiger 6, right parapodium, neurochaetae. E. Same, chaetiger 27, right parapodium, neurochaetae. Scale bars: A: 0.8 mm, B: 0.9 mm, C: 0.4 mm, D: 0.2 mm, E: 0.1 mm.