Chloeia amphora Horst, 1910

Salazar-Vallejo, Sergio I., 2023, Revision of Chloeia Savigny in Lamarck, 1818 (Annelida, Amphinomidae), Zootaxa 5238 (1), pp. 1-134 : 23-27

Chloeia amphora Horst, 1910

Figs 1A , 9–11

Chloeia amphora Horst, 1910: 172–173, 1912: 21–22 , Pl. 7, Fig. 6 , Pl. 8, Figs 6 , 7 ; Fauvel 1932: 56, 1953: 96–97, Fig. 46c ; Hartman 1959: 131; Bleeker & van der Spoel 1992: 127 (design. lectotype); Barroso & Paiva 2011: 422, Tab. 1; SalazarVallejo et al. 2014: 11 (list).

Type material. Indonesia, Lectotype ( ZMA V.Pol 149.4), designated by Bleeker & van der Spoel (1992), Maluku, RV Siboga Exped., Stat. 240 (Banda anchorage), 9–45 m, trawl + dredge + reef expl., black sand and coral, 22 Nov. – 1 Dec. 1899 ( Bleeker & van der Spoel 1992: 127 indicated the lectotype was their lot V.Pol 149.1 but the label is in V.Pol 149.4). One paralectotype ( ZMA V.Pol 149.1), Lesser Sunda Islands, RV Siboga Exped., Stat. 303 (Samau Isl., Haingsisi), 36 m, dredge, reef expl., 2–5 Feb. 1900 (20 mm long, 6 mm wide, 25 chaetigers).

Additional material. Philippines. One specimen ( CAS 187535 ), Hearst Biodiversity Expedition 2011, Luzon Islands , Batangas Province, Tingloy , Maricaban Island , Cemetery Beach (13.68° N, 120.83° E; 13°40´47.9994″ N, 120°49´47.9994″ E), 19 May 2011, D. de la Rosa, coll. (complete, slightly bent laterally; anterior eyes 2× larger than posterior ones. Median antenna without tip, 2/3 as long as caruncle; body 30 mm long, 6 mm wide, 25 chaetigers). One specimen ( CAS 217699 ), Verde Island Passage Expedition 2016, Visayas , Negros Island , Negros oriental, Dauin , San Miguel dive site (09.20° N, 123.28° E; 9°11´59.9994″ N, 123°16´48″ E), 6.5 m, 2 Apr. 2016, T.M. Gosliner, coll. (complete, pigmentation retained, middorsal band with roughly parallel sides; a small ventral section removed for molecular studies; body 40 mm long, 10 mm wide, 27 chaetigers). One specimen ( CAS 217701 ), Verde Island Passage Expedition 2016, Visayas , Negros Island , Negros oriental, Dauin , VIP Resort House reef (09.20° N, 123.27° E; 9°11´59.9994″ N, 123°16´11.9994″ E), 6–32 m, 6 Apr. 2016, J. Comendador, coll. (pigmentation retained; a few chaetae broken; body 34 mm long, 8 mm wide, 24 chaetigers). One specimen ( CAS 217710 ), Verde Island Passage Expedition 2016, Visayas , Negros Island , Negros oriental, Pyramid dive site (09.17 N, 123.25 E; 9°10´11.9994" N, 123°15´0" E), 3–27 m, sand, 7 Apr. 2016, J. Comendador, coll. (complete; middorsal bands subrectangular in median segments, tapered along posterior ones; oval shaped; paler bands along anterior notopodial surfaces. Anterior neurochaetae along median and posterior chaetigers reddish. Median antenna 4/5 as long as caruncle; body 32 mm long, 7.5 mm wide, 24 chaetigers). One specimen ( CAS 217726 ), Verde Island Passage Expedition 2016, Visayas , Negros Island , Negros oriental, Dauin , San Miguel dive site (09.20° N, 123.28° E; 9°11´59.9994″ N, 123°16´48″ E), 6–32 m, 9 Apr. 2016, C. Piotrowski, coll. (bent ventrally; pigmentation retained; some chaetae broken; body 30 mm long, 8 mm wide, 24 chaetigers). Three specimens ( CAS 218219 ), Verde Island Passage Expedition 2016, Visayas , Negros Island , Negros oriental, Zamboanguita , off Basak Barangay (09.10° N, 123.21° E; 9°5´59.9994″ N, 123°12´35.9994″ E), 6–27 m, sand, 4 Mar. 2016, C. Piotrowski, coll. (complete, pigmentation retained in one specimen; some chaetae broken; body 26–41 mm long, 6.5–7.5 mm wide, 23–26 chaetigers). Two specimens ( UF 4369 ), Oriental Mindoro Province, Mindoro , Puerto Galera , off Sabang Beach (13.52207, 120.97522; 13°31´19.4514″ N, 120°58´30.7914″ E), gentle sand slope with some reef blocks, 4–6 m, 13 Apr. 2015, G. Paulay, coll. (complete 16 mm long, 4.5 mm wide, 24 chaetigers; pigmentation almost completely faded off, middorsal band modified; details in variation). One specimen ( ZMA V.Pol 149.2 ), Sulu Islands, RV Siboga Exped., Sta. 104 (Sulu Harbour), 14 m, dredge, sand, 2–3 Jul. 1899 (12 mm long, 3 mm wide, 21 chaetigers). Two specimens ( ZMA V.Pol 149.3 ), Sulu Islands, RV Siboga Exped., Sta. 104 (Sulu Harbour), 14 m, dredge, sand, 2–3 Jul. 1899 (18–21 mm long, 5–6 mm wide, 24 chaetigers) .

Diagnosis. Chloeia with bipinnate branchiae from chaetiger 4, progressively smaller posteriorly; middorsal spots amphora-like, slightly wider anteriorly, thinner medially, rounded posteriorly, surrounded by a pale thin band; harpoon notochaetae with spurs; neurochaetae spurred and furcates.

Description. Lectotype (ZMA V.Pol 149.4), complete, slightly damaged, many chaetae broken; left notopodia of chaetigers 4–7, and right notopodia of chaetigers 13, 14 previously removed ( Fig. 9A ). Body fusiform, 27 mm long, 7 mm wide, 24 chaetigers

Lectotype brownish; middorsal spots with anterior half brownish, better defined along anterior to median segments, posterior half blackish ( Fig. 9B ); paler halo along lateral and posterior margins better defined along anterior to median chaetigers. Lateral bands along anterior notopodial surface better defined along anterior to median segments ( Fig. 9C ). Dorsal cirri blackish. Chaetae transparent to golden. Venter with pairs of irregular large darker areas per segment, midventral band paler along body.

Prostomium anteriorly entire. Eyes blackish, anterior eyes about 2× larger than posterior ones. Median antenna inserted at anterior caruncular margin, in a paler area, without tip, ¾ as long as caruncle (2/3 as long in ZMA V.Pol 149.1), lateral antennae lost, size relationship to median antenna unknown (2× longer than laterals in ZMA V.Pol 149.1). Lateral antennae bases close to each other, size relationship to palps unknown (2× longer in ZMA V.Pol 149.1). Mouth ventral on chaetiger 3. Pharynx barely exposed, basal smooth rings short; outer ring visible in its tip, not exposed (ZMA V.Pol 149.1 with pharynx fully exposed, turned upwards; two muscular rings, dorsally reduced, followed by a long basal ring with transverse series of thin ridges; distal ring separated in two lateral halves, each with transverse series of continuous warts or verrucae, converging in pharynx opening).

Caruncle pale, sigmoid, trilobed, tapered, reaching chaetiger 4. Median ridge plicate, with a brownish band, about 17 vertical folds (25 in ZMA V.Pol 149.1), partially concealing lateral lobes (almost completely concealing them in ZMA V.Pol 149.1). Lateral lobes narrow, with about 18 vertical folds.

Bipinnate branchiae from chaetiger 4, continued throughout body, parallel along body; progressively larger to chaetiger 10–11, smaller posteriorly, slightly longer than following segments in median chaetigers, each with 8–9 lateral branches.

Parapodia biramous, notopodia with cirriform branchiae along chaetigers 1–3, ½ as long as dorsal cirri. Dorsal cirri 2× longer than bipinnate branchiae along median chaetigers, 3× longer in posterior chaetigers. Second ventral cirri with cirrophores 2× longer and wider, and cirrostyle 2× longer than adjacent ones, directed dorsally. Other ventral cirri directed ventrolaterally, as long as two subsequent segments.

Chaetae many broken. Complete chaetae with distal hoods, rarely eroded. Notochaetae in anterior chaetigers furcate, major tines golden, 3–4× longer than minor ones ( Fig. 9D ). Median chaetigers with aciculars and harpoon notochaetae, some with golden medial area, smooth tines 2–9× longer than wide, others without spurs ( Fig. 9F ). Neurochaetae all furcates, major tines 2–5× longer than minor ones in anterior chaetigers ( Fig. 9E ), 3—4× longer in posterior chaetigers ( Fig. 9G ).

Posterior region tapered ( Fig. 9H ), pygidium with anus terminal, anal cirri pale, tapered, 6–7× longer than wide.

Live pigmentation (after recently collected specimens CAS 217699, 217726, 218219, Figs 1A , 10G, H , Rendive (2010), and Castello (2019)). Dorsum pale orange, parapodia paler. Pigmentation pattern with discontinuous middorsal dark purple spots, each amphora-like, anterior half paler, often brownish, posterior half blackish. Amphora-like spots surrounded by a thin pale band, rarely with roughly parallel sides, or thin whitish halo along lateral and posterior margins, surrounded by two darker thin bands, forming a large circular spot including the amphoralike spots, or dark encircling areas in orange or barely developed. Lateral bands brownish, dark purple along anterior notopodial lobes, diverging V-shaped along anterior chaetigers, becoming transverse in median and posterior chaetigers continued along anterior prostomial surfaces. Dorsal cirri dark purple. Bipinnate branchial stems pale, lateral branches purplish to reddish. Chaetae whitish to yellowish.

Variation. Paralectotypes variably damaged; some features of the best preserved one were added in description above. Paralectotypes with body 12–21 mm long, 3–6 mm wide, 21–25 chaetigers. The pigmentation pattern is less defined in the smallest lectotype (ZMA V.Pol 149.2, Fig. 10A, B ); the middorsal spots are not fully developed and the pale surrounding halo is not visible. The middorsal spots become progressively better defined and the paler halo is visible in median segments of 18 mm long specimens, each spot becoming progressively wider with the pale halo visible ( Fig. 10C, D ), and in slightly larger specimens (ZMA V.Pol 149.3), being 21 mm long, median segments have a better-defined amphora-like spot with its paler halo ( Fig. 11E, F ). However, the anterior part might fade, often simultaneously with other pigments, resulting in a longitudinal band, truncate anteriorly, posteriorly tapered, extended along half a segment.

Two other specimens (UF 4369) show a marked reduction of overall pigmentation including dorsal cirri, and additional banding pigmentation ( Fig. 11A ), and median ridge of caruncle ( Fig. 10B ); even the middorsal spots are also modified, such that the anterior, usually paler anterior portion completely disappears, and the posterior one becomes shorter, and its posterior margin is blunt, not tapered ( Fig. 11C ). There are no differences in anal cirri ( Fig. 11D ), or chaetae in anterior ( Fig. 11E, F ), or median chaetigers ( Fig. 11G, H ).

Remarks. Chloeia amphora Horst. 1910 belongs in the group viridis by having bipinnate branchiae from chaetiger 4, progressively smaller posteriorly, and a complex pigmentation pattern. Horst (1910: 172) chose the specific epithet because “each segment shows a violet spot, somewhat resembling a roman amphora, surrounded by a white band.” He also noted that “in the anterior segments an oblique (purple) band is visible, running over the front-side of the parapodium.”

Chloeia amphora resembles C. maculata Baird, 1868 described from Saint Brandon Rocks (Cargados Carajos), Indian Ocean (see below), because in the former, the middorsal spots are less defined in smaller specimens. However, a comparison of specimens of similar size confirms that in C. amphora the spots are not well defined in smallest specimens, about the same size as the holotype of C. maculata , but continue to be in larger specimens, whereas in C maculata the band is restricted to the posterior segmental half, even in larger specimens. Further, the holotype of C. maculata (13 mm long) is markedly wider than the smallest paralectotype of C. amphora (12 mm long), which might imply that it was longer and became contracted after fixation, such that it should be compared with larger specimens of C. amphora .

Chloeia amphora also resembles C. bimaculata Wang, Zhang, Xie & Qiu, 2019 described from Hong Kong, because the latter has dorsal spots varying from an amphora like spot along chaetigers 3–7, and then each spot becomes separated, as indicated in the specific epithet. Despite the fact Wang et al. (2019) did not include comparisons with other species, these two species differ, although slightly regarding the shape of spots, and especially in some chaetal features. In C. amphora , the anterior notochaetae are furcates with golden tines, and harpoon notochaetae have a well-developed spur, whereas C. bimaculata has anterior notochaetae spurred, barely pigmented or pale, and its harpoon notochaetae are smooth, or have a tiny spur.

Distribution. Indonesia to the Philippines, in sediments from the intertidal to 45 m water depth.

Figures

FIGURE 1. Living specimens of four Philippine species of Chloeia Savigny in Lamarck, 1818. A. C. amphora Horst, 1910, dorsal view. B. C. bemisae sp. n., pink variant, dorsal view. C. Same, reddish and brownish variants, dorsal view. D. C. flava (Pallas, 1766), oblique right dorsal view. E. C. violacea Horst, 1910, oblique left dorsal view (scales not available; photos: Philippe Poppe; © Philippe & Guido Poppe – www.poppe-images.com).

FIGURE 6. Chloeia bistriata Grube, 1868, non-type specimens (from UF 4449, 4517). A) Small juvenile (1.4 mm long, 11- 12 chaetigers), dorsal view, depressed by a cover slip. B) Same, dorsal view (* indicates enlarged area of chaetigers 7-8). C) Chaetigers 7-8, right parapodia, seen from above (* convoluted dorsal cirri). D) Larger juvenile, chaetae combed backwards, depressed by cover slip, without posterior region (3.5 mm long, 14-15 chaetigers), after Shirlastain-A staining (5: left notopodium, chaetiger 5; MA: median antenna). E) Same (5: chaetiger 5). F) Same, close-up of anterior region, dorsal view (BB: bipinnate branchia, CB: cirriform branchia, DC: dorsal cirrus). Scale bars: A, 0.23 mm, B: 0.20 mm, C, F: 0.1o mm, D: 0.55 mm, E: 0.50 mm.

FIGURE 7. Chloeia amoureuxi sp. n., holotype (MMSUCO Amp 2). A. Oblique dorsal view. B. Anterior end, left lateral view. C. Median segments, dorsal view. D. Chaetiger 3, notochaetal tips. E. Same, neurochaetal tips. F. Chaetiger 16, harpoon notochaetae. G. Same, neurochaetal tips. H. Posterior region, dorsal view. Scale bars: A, 0.7 mm; B, 0.05 mm; C, 1.5 mm; D, 160 μm; E, 110 μm; F, 180 μm; G, 30 μm; H, 2 mm.

FIGURE 9. Chloeia amphora Horst, 1910, lectotype (ZMA V.Pol 149.4). A. Oblique dorsal view. B. Anterior region, dorsal view. C. Chaetigers 10-12, dorsal view. D. Chaetiger 3, notochaetae. E. Same, neurochaetal tips. F. Chaetiger 12, notochaetal tips (inset: spur). G. Same, neurochaetal tips. Scale bars: A, 4.2 mm; B, 2.4 mm; C, 0.6 mm; D, 130 μm; E, G, 30 μm; F, 90 μm; H, 1.7 mm.

FIGURE 10. Chloeia amphora Horst, 1910.A. Paralectotype (ZMA V.Pol 149.2), dorsal view. B. Same, chaetigers 7-11, dorsal view. C. Paralectotype (ZMA V.Po. 149.3), dorsal view. D. Same, chaetigers 11-15, dorsal view. E. Another paralectotype, same lot, dorsal view. F. Same, chaetigers 12-16, dorsal view. G. Non-type specimen (CAS 218219), anterior region, dorsal view. H. Same, posterior region, dorsal view. Scale bars: A, 1.6 mm; B, 0.6 mm; C, 2.4 mm; D, 0.8 mm; E, 2.5 mm; F, 0.4 mm; G, H, 1.8 mm.

FIGURE 11. Chloeia amphora Horst, 1910, non-type specimens (UF 4369). A. Dorsal view. B. Anterior end, dorsal view, after Shirlastain-A pigmentation. C. Chaetigers 10-12, dorsal view (left branchia of chaetiger 10 removed). D. Posterior end, ventral view. E. Another specimen, chaetiger 3, notochaeta (insets: notochaetal tips). F. Same, neurochaetal tips. G. Chaetiger 12, harpoon notochaetae. H. Same, neurochaetal tips. Scale bars: A, 1.5 mm; B, 0.5 mm; C, 0.4 mm; D, 0.7 mm; E, 110 μm; F, 70 μm; G, 160 μm; H, 40 μm.

FIGURE 46. Chloeia pulchella Baird, 1868, reinstated.A. Holotype of C. p. pallida Baird, 1868 (BMNH 1846.10.14.60), anterior end, dorsal view, after Methyl green staining. B. Chaetigers 17-20, dorsal view. C. Posterior region, dorsal view. D. Syntype of C. incerta de Quatrefages, 1866 (MNMH IA-TYPE 248), beheaded, anterior end, dorsal view. E. Chaetigers 16-19, dorsal view. F. Posterior region, dorsal view. Scale bars: A, E, 0.9 mm; B, 1.1 mm; C, 1.5 mm; D, 1.4 mm; F, 1.9 mm.