Lamispina horsti ( Haswell, 1892 ) Salazar-Vallejo, 2014

Salazar-Vallejo, Sergio I., 2014, Revision of Pherusa Oken, 1807 (Polychaeta: Flabelligeridae), Zootaxa 3886 (1), pp. 1-61 : 49-50

Lamispina horsti ( Haswell, 1892) n. comb.

Figure 21

Stylarioides horsti Haswell 1892:335–336 , Pl. 26, Figs 6–8 , Pl. 27, Fig. 17 .

Material examined. Australia. One specimen ( GR 197 ), under Edithburgh Jetty (35°05.172' S, 137°44.825' E), Adelaide , South Australia, 5 m, in sediment, 9 Feb. 2004, G. Rouse, coll. One specimen ( USNM 1132081 ), breaking in two, Orpheus Island , Great Barrier Reef, Sta. JDT & OPH 1, 1– 2 m, 12 Feb. 1989, Thomas & Clark, coll. (22 mm long, 2 mm wide, cephalic cage 3.5 mm long, 58 chaetigers) .

Description. Body pale, complete (GR 197) slightly distorted, anteriorly swollen, posteriorly tapered ( Fig. 21A ), posterior end in regeneration; 19.5 mm long, 2 mm wide, cephalic cage 5 mm long, 45 chaetigers. Body papillae digitate, larger dorsally, arranged in 3–5 transverse series per segment anteriorly, 3–4 series posteriorly. Each papilla stiff, with fine sediment basally, subdistally widened; some anterior dorsal papillae with sand grains ( Fig. 21B ).

Anterior end exposed. Cephalic hood very short, margin with tiny papillae, looking smooth. Prostomium low cone; four large, ovoid eyes, slightly pigmented ( Fig. 21C ). Caruncle short triangular, posteriorly fused, lateral lobes pale. Palps thick, pale, palp keels low, rounded; without lateral lobes. Lateral lips pale, thick, projected; dorsal and ventral lips reduced.

Branchiae cirriform, arranged in a continuous row with 4 filaments, and two lateral groups each with two filaments. Branchiae smaller than palps. Interbranchial lobes reduced. Nephridial lobes very thin, short, placed between bases of inner branchiae in anterior row.

Cephalic cage chaetae as long as ¼ body length, or 2.5x longer than body width. Chaetigers 1–2 forming cephalic cage; chaetae arranged in short lateral series. Chaetiger 1 with 10 noto- and 8 neurochaetae; chaetiger 2 with 10 noto- and 6 neurochaetae. Anterior dorsal margin of first chaetiger papillated. Chaetigers 1–3 progressively longer. Chaetal transition from cephalic cage to body chaetae abrupt; anchylosed, falcate blunt lamispines start from chaetiger 4. Gonopodial lobes not seen.

Parapodia poorly developed, chaetae emerge from body wall ( Fig. 21F ). Parapodia lateral, medial neuropodia ventrolateral. Noto- and neuropodia without projected lobes; some slightly longer papillae in chaetal lobes, 1–2 pre- and 2–3 postchaetal on notopodia; 2–3 pre- and 3–4 postchaetal on neuropodia.

Medial notochaetae arranged in short, transverse series; all notochaetae multiarticulated capillaries, articles short basally, long medially and distally ( Fig. 21D, F insets); 5–6 notochaetae per bundle, as long as half body width in swollen region, longer than body width in posterior (regenerating) region. Neurochaetae multiarticulated capillaries in chaetigers 1–3; anchylosed, falcate subidstally widened lamispines from chaetiger 4, arranged in transverse series, each with 4–5 hooks ( Fig. 20E ), more delicate in posterior chaetigers ( Fig. 21G ).

Posterior end truncate; pygidium with anus terminal, without anal cirri.

Remarks. The taxonomic status of Lamispina horsti ( Haswell, 1892) n. comb. needs clarification; Hartman (1959:421) regarded L. horsti as a junior synonym of L. kerguelarum ( Grube, 1877) n. comb. (see below). They differ especially in the start of lamispines and in their relative length; in L. horsti they are short and start in chaetiger 4, whereas in L. kerguelarum they are longer and start in chaetiger 3.

The proposal of a neotype for L. horsti together with a description and illustrations of it would clarify its taxonomic status ( ICZN 1999, Art. 75.3.1–75.3.3). The original type material is lost ( Day & Hutchings 1979:83, 133; ICZN 1999, Art. 75.3.4), and because the original description failed to clarify some critical features, it seems that the specimen described in detail above (GR 197) might correspond to this species ( ICZN 1999, Art. 75.3.5). However, this specimen was collected off Adelaide far away from the type locality (off Sydney), and because there is a sharp biogeographic discontinuity in Bass Pass ( Waters & Roy 2003), it would be questionable to certify that this specimen is conspecific with the original species, and consequently, the proposal of a neotype must be postponed until better, specimens are found. Haswell (1892:335) had two specimens; the largest had its posterior six chaetigers undergoing regeneration; he stated that there was no sand incrustation (in comparison to the other species he described, Daylithos cinctus ) and that neurohooks began on chaetiger 3, but this could be due to confusion about segment counting because the first chaetiger is dorsally displaced. All other features fit with the present specimens.

Lamispina horsti ( Haswell, 1892) n. comb. groups with L. carrerai n. sp. and L.gymnopapillata (Hartmann- Schröder, 1965), n. comb. by having stiff body papillae, and subdistally widened, falcate lamispines. As already indicated, L. carrerai can be separated from the other species because of its very long cephalic cage (6 x longer than body width), whereas the two other species have shorter cephalic cages (2–3x longer than body width). The remaining two species can be separated by the number of notochaetae per bundle, and transverse series of papillae per segment; in L. horsti there are 5–6 notochaetae per bundle, and 3–5 transverse series of papillae per segment, whereas L. gymnopapillata has more notochaetae (10 per bundle), and slightly more transverse series of papillae (4–6) per segment.

Distribution. These specimens are from the Great Barrier Reef, but the species was described from Sydney. Then if they belong to the same species, it would range at least along these two localities, in shallow water (1–5 m depth).

Figures

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 8. Pherusa moorei n. sp., holotype (USNM 5391). A. Dorsal view. B. Anterior end, dorsal view. C. Anterior end, ventral view. D. Chaetiger 12, notochaetae (insets: basal, medial and distal regions). E. Chaetiger 9, neurochaetae (inset: tips of two chaetae). F. Chaetiger 33, neurochaetae (insets: tips of chaetae). Scale bars: A: 2.2 mm, B: 1.7 mm, C: 1.5 mm, D: 0.4 mm, E: 260 µm, F: 200 µm.

FIGURE 17. Lamispina carrerai n. sp., holotype (USNM 17387). A. Complete specimen, dorsal view (anterior fragment at left). B. Anterior end, dorsal view. C. Anterior fragment, terminal segments, dorsal view. D. Chaetiger 11, right parapodium, notochaetae (inset: tips). E. Chaetiger 11, right parapodium, lamispines (inset: medial and distal regions). F. Posterior fragment, posterior end, dorsal view. Scale bars: A: 2.5 mm, B: 0.5 mm, C: 0.6 mm, D, E: 160 µm, F: 0.3 mm.

FIGURE 20. Lamispina gymnopapillata (Hartmann-Schröder, 1965) n. comb., holotype (ZMH 14913). A. Dorsal view, sunlight illumination. B. Same, microscope lamp illumination. C. Anterior end, dorsal view. D. Anterior end, right side, ventral view. E. Chaetiger 14, right parapodium, notochaetae (inset: medial regions). F. Chaetiger 9, right neuropodium, lamispines. Scale bars: A: 1.9 mm, B: 2 mm, C: 0.6 mm, D: 0.3 mm, E: 0.25 mm, F: 0.15 mm.

FIGURE 21. Lamispina horsti (Haswell, 1892) n. comb., non-type specimen (GR 197). A. Complete specimen, twisted, anterior end in dorsal view. B. Anterior end, dorsal view (Br: branchia, Pa: palp). C. Head, frontal view (branchiae and one palp removed; BS: branchiae scar, LL: lateral lip, Pa: palp, PS: palp scar). D. Chaetiger 10, right parapodium, notochaetae (four others broken, not shown). E. Same, neuropodium, lamispines. F. Chaetiger 25, right parapodium, posterior view (insets: notochaetal basal, medial and distal regions). G. Same, neuropodium, lamispines. Scale bars: A: 1.2 mm, B: 0.5 mm, C, G: 140 µm, D: 230 µm, E: 150 µm, F: 370 µm.