Chloeia flava (Pallas, 1766)

Salazar-Vallejo, Sergio I., 2023, Revision of Chloeia Savigny in Lamarck, 1818 (Annelida, Amphinomidae), Zootaxa 5238 (1), pp. 1-134 : 45-49

Chloeia flava (Pallas, 1766) restricted

Figs 1D , 19 , 20

Aphrodita flava Pallas, 1766a: 97–102 , Pl. 8, Figs 7–11 .

Amphinome capillata Bruguière, 1789: 45–46 (unnecessary repl. name).

Chloeia capillata: Savigny 1822: 58–59 ; Milne-Edwards 1837, Pl. 9, Fig. 1 .

Terebella flava: Milne-Edwards 1837:31 .

Chloeia flava: de Quatrefages 1866: 386–388 , Pl. 17, Fig. 4 ; Willey 1905: 244–245, Pl. 1, Figs 1 , 2 (syn.); Kinberg (1910: 33, Pl. 11, Fig. 1 ); Augener 1926: 436; Fauvel 1932: 55; Fauvel 1953: 96, Fig. 46d, i ; Hartman 1959: 131; Amoureux et al. 1978: 73; Barroso & Paiva 2011: 422, Tab. 1 (partim); Yáñez-Rivera & Salazar-Vallejo 2022: 516–517, Fig. 6 .

Chloeia ceylonica Grube, 1874: 326 .

Type locality. Indian Ocean, Bay of Bengal, Punducherry , India, after neotype MNHN 247 .

Type material. Indian Ocean, Bay of Bengal, India. Neotype ( MNHN IA-TYPE 247 ), Punducherry (Pon-dicherry, 11°55′N 79°49′E), Leschenault, coll. (no further data). Paraneotype ( MNHN 252 ), Ennore (13°13′03″ N, 80°19′17.58″ E) (no further data).

Additional material. India. One specimen ( MNMH 399.1 ), Andaman, Port Blair , caught with a fishing line baited with meat, no date or collector data, from the Indian Museum (middorsal spots dark purple, circular along anterior and median chaetigers, oval, longer than wide in posterior region; lateral bands continued along anterior parapodial surfaces; dorsal cirri colorless; branchial stems pale, branches purplish; caruncle median ridge dark purple; chaetae with yellowish band distally; anterior end damaged by compression; body 85 mm long, 15 mm wide, 39 chaetigers) . Burma. One specimen ( BMNH 1938.5.7.12 ), RV Investigator, Sta. number unknown, Mergui, no further data (whitish, middorsal spots purple, circular along most chaetigers from chaetiger 4, oval to elongate along last 9 chaetigers; bipinnate branchiae from chaetiger 4, whitish; body 56 mm long, 16 mm wide, 37 chaetigers). One specimen ( ZMA VPol 151 ), no further data (bent ventrally; middorsal spots purple, oval; branchiae pale, from chaetiger 4; pharynx exposed; anal cirri subcylindrical, blunt, 6–7× longer than wide; body 74 mm long, 21 mm wide, 37 chaetigers) . Thailand. One specimen ( CAS 188790 ), Vanderbilt Gulf of Thailand Survey, Ban Aantong Bay , Goh Samui Island , anchoring (09°30´03″ N, 99°56´00″ E), intertidal, collected swimming at surface at 16:30, 7 Nov. 1957, Fehlman & Rofen, coll. (bent ventrally, branchiae and notochaetae obliterating middorsal circular spots; eyes black, minute, anterior eyes larger than posterior ones; W. Light regarded it as a possible new variety, 1 Aug. 1968, probably after the tiny eyes and being caught swimming; body 82 mm long, 19 mm wide, 40 chaetigers) . Singapore. One specimen ( RMNH 1227 ), 1907, P. Buittendijk, no further data (complete, pharynx exposed, anterior end distorted by compression in small container; middorsal spots circular, roughly rectangular in last 7 chaetigers; body 63 mm long, 17 mm wide, 34 chaetigers) . Indonesia. One specimen ( ZMA VPol 155b ), Batavia (Jakarta), Java, Mar. 1911, Buittendijk, coll. (body straight; middorsal spots oval long anterior body third, circular in median and posterior regions; 30 mm long, 6 mm wide, 29 chaetigers). New Guinea. One specimen ( RMNH 1224 ), Fak-Fak , 19 Sep. 1908, P. van den Broek, coll. (posterior end bent dorsally; middorsal spots circular, oval in last 7 chaetigers; body 64 mm long, 17 mm wide, 35 chaetigers) . Taiwan. One specimen ( ZMH V7217 ), Hai-gia-kang , Takao , 29 Apr. 1907, H. Santer, coll. (complete; anterior end distorted by exposed pharynx; middorsal spots circular, reddish, barely defined; dorsal cirri reddish; branchial stems pink; chaetae golden; body 34 mm long, 9 mm wide, 28 chaetigers) . Australia. One specimen ( AM V998 ), Queensland, Bewick Island, Barrier Reef (14° 25´S, 144° 48´E), 5 Oct 1923 (complete; middorsal spots circular, margins diffuse; anterior end collapsed by compression in smaller container; chaetae golden; body 150 mm long, 25 mm wide, 40 chaetigers). One specimen ( AM W24643 ), Western Australia, Admiralty Gulf (14°23´S, 125°48´E), Otter trawl, Apr. 1978, C. O’Conner, coll. (middorsal dark purple spots circular along body; dorsal cirri with purplish cirrophores; branchiae pale; body 94 mm long, 22 mm wide, 41 chaetigers). One specimen ( ZMH V12088 ), Port Alina , Queensland, Jun. 1921, H. v. d. Poel, coll. (complete, bent dorsally, pharynx exposed by fracture of dorsal body wall, distorting anterior end; middorsal spots circular, dark purple, along anterior and median chaetigers, oval, purple along posterior chaetigers; dorsal cirrophores dark purple along inner surface; branchiae pale; chaetae with tips yellowish-green, especially along anterior chaetigers; venter pale, midventral band narrow, pale; body 117 mm long, 26 mm wide, 42 chaetigers) .

Diagnosis. Chloeia with bipinnate branchiae from chaetiger 4, progressively smaller posteriorly; middorsal spots black, circular; notochaetae furcates and harpoon-chaetae with spurs; neurochaetae furcates.

Description. Neotype (MNHN 247) complete, pharynx partially exposed ( Fig. 19A ), with an anterior ventral dissection; body fusiform, 120 mm long, 23 mm wide, 39 chaetigers.

Neotype with chaetae golden to yellowish; anterior prostomial margin brownish; dorsum with circular black spots middorsally, one per segment, blunt shield-like to circular along anterior and median chaetigers ( Fig. 19C ), oval to blunt rectangular along posterior chaetigers, displaced posteriorly on each segment; an anterior darker area visible in several segments; branchiae with pale stem, brownish lateral branches, especially thinner ones; dorsal cirri with blackish ceratophores, dorsal ceratostyles and ventral cirri pale. Venter pale.

Prostomium anteriorly entire. Eyes blackish, anterior eyes slightly larger than posterior ones. Median antenna inserted at anterior caruncular margin, 1/3 as long as caruncle, slightly longer than lateral antennae. Lateral antennae bases separated from each other, slightly longer than palps. Mouth ventral on chaetiger 3, distorted by dissection. Pharynx partially exposed, smooth basal rings partially shown.

Caruncle pale, slightly twisted, trilobed, tapered, reaching chaetiger 5 ( Fig. 19B ). Median ridge plicate, blackish, with about 35 vertical folds, partially concealing lateral lobes. Lateral lobes narrow, with about 38 vertical folds.

Bipinnate branchiae from chaetiger 4, continued throughout body, alignment, mostly parallel, convergent in a few chaetigers; progressively larger up to chaetigers 11–12, of similar size in posterior segments, shorter in far posterior segments. Median segments with 9–10 lateral branches.

Parapodia biramous, notopodia with cirriform branchiae along chaetigers 1–3, 1/3–1/4 as long as dorsal cirri. Dorsal cirri as long as bipinnate branchiae along a few anterior chaetigers, becoming longer than bipinnate branchiae along median and posterior chaetigers. Second ventral cirri with cirrophores and cirrostyles slightly longer than those present in adjacent ones, not directed dorsally. Other ventral cirri directed ventrolaterally, as long as one subsequent segment.

Chaetae most without tips. Complete chaetae with distal fragile brownish to pale hoods. Notochaetae in anterior chaetigers furcate, major tines 2–3× longer than minor ones. Median chaetigers with two types of notochaetae: spurred harpoon chaetae, and furcates with reduced minor tines, major ones 8–9× longer than minor ones; neurochaetae all furcates, major tines 4–5× longer than minor ones.

Posterior region tapered; pygidium with anus terminal; anal cirri brownish, digitate, 5–7× longer than wide ( Fig. 19D ).

Paraneotype (MNHN 252) complete, 47 mm long, 13 mm wide, 35 chaetigers ( Fig. 20A ). Dorsum and venter whitish; middorsal spots circular along chaetigers 5–13, following chaetigers with oval spots up to chaetiger 28, slightly longer than wide, far posterior chaetigers with longer than wide spots ( Fig. 20C ), last ones blunt rectangular. Spots usually covering half segmental length, displaced posteriorly. Chaetae whitish; venter pale.

Eyes blackish, anterior ones 2× larger than posterior ones. Median and lateral antennae with tips blackish ( Fig. 20B ); median antennae half as long as caruncle, about 2× longer than lateral antennae. Lateral antennae slightly longer than palps.

Bipinnate branchiae from chaetiger 4, stems pale, lateral branches purple; branchiae largest by chaetigers 7–8, about as long as successive segments, mostly parallel along body. Median segments with 8–9 lateral branches per branchia.

Anterior furcate notochaetae with major tines 4× longer than minor ones ( Fig. 20D ); anterior furcate neurochaetae with major tines 3× longer than minor ones ( Fig. 19E ). Median chaetigers with harpoon notochaetae ( Fig. 20F ), with a very small basal spur (inner complex structure); neurochaetae furcates with major tines 2—4× longer than minor ones ( Fig. 20G ).

Posterior region tapered; pygidium with anus terminal; anal cirri pale, digitate, 5–6× longer than wide ( Fig. 20H ).

Variation. Pigmentation pattern is modified after preservation, and most specimens retaing the middorsal circular spots along median segments, becoming oval along anterior and posterior regions.

Live pigmentation. No photos available from Indian Ocean specimens. Photos from Singapore (WildSingapore 2022) and Philippine specimens ( Fig. 1D ) show a pink dorsum with large black round spots per segment, each with a white halo, and wide purplish bands running laterally. Caruncle pale with blackish median ridge. Bipinnate branchiae red; dorsal cirri dark purple. Chaetae golden. A recently washed up on beach specimen shows middorsal black spots and their white halo over an orange background; bipinnate branchiae with dark purple lateral branches tips, and golden banding in notochaetae, and brownish in neurochaetae. This is the species most frequently shown in internet videos ( Japan 2012, Muhmuh1091 2012, Man 2016, Tigersgoochan 2017, Tsujita 2018, Ameblo 2020, Tsujita 2022, GMT 2021, Senja 2021, Maverick 2022).

Remarks. Chloeia flava (Pallas, 1766) has been regarded as a well-known species, with a wide distribution from the Indian Ocean to Japan, the Philippines and Australia. The type locality is the Bay of Bengal, but it seems that the type specimens, one from the Bay of Bengal, the other from Amboina, were not deposited. The lack of type specimens in an apparently widely distributed species emphasizes the need for the proposal of a neotype for delineating the species ( ICZN 1999, Art. 75.3). The neotype proposed above will clarify the taxonomic status and the type locality of C. flava ( ICZN 1999, Art. 75.3.1). The diagnosis and description include the characters that separates this species from similar ones ( ICZN 1999, Art. 75.3.2, 75.3.3). There are no type specimens in Leiden (J. Blekker, in litt.), nor in Saint-Petersburg (S. Gagaev, 2021, in litt), where some other Pallas’ specimens were deposited or transferred ( ICZN 1999, Art. 75.3.4). The neotype matches the original description and illustrations ( ICZN 1999, Art. 75.3.5), and was collected in the Bay of Bengal, Indian Ocean, where the original specimen was found ( ICZN 1999, Art. 75.3.6). Further, the neotype, and the neoparatype are deposited in the Muséum National d’Histoire Naturelle, Paris ( ICZN 1999, Art. 75.3.7).

As herein restricted, C. flava is characterized by having circular middorsal spots in median segments; it belongs in the group flava by having bipinnate branchiae from chaetiger 4, progressively smaller posteriorly, and dorsal spots oval to circular. There are two other species in the same group: C. pulchella Baird, 1868 reinstated, characterized by having oval dorsal spots (longer than wide), in median segments, and described from Northeastern Australia, and C. maculata Potts, 1909 , characterized by having half-oval dorsal spots, and described from the Western Indian Ocean. Consequently, C. flava is the only species in the group having circular dorsal spots.

Pallas (1766: 101) emphasized the yellow color of the chaetae, and hence the selection of the Latin adjective (flavus, a, um: yellow). One of the original illustrations (Pl. 8, Fig. 7 ) shows a series of middorsal round, dark spots per segment, each about 1/2–2/3 segment length. M’Intosh (1885, Pl. 3, Fig. 1 ) made an additional figure after a specimen from Japan, showing the dorsal spots are circular along most segments, becoming oval in the far posterior ones, and of similar size as illustrated by Pallas. He also indicated (Pallas 1766: 97–98) he studied two specimens, one was caught adhered to the anchor in the Bay of Bengal, and another smaller specimen from Amboina. Because the description and illustrations were based upon the largest specimen, Bengal Bay is regarded as the type locality, although Hartman (1959) gave the Indian Ocean as the type locality.

Milne-Edwards (1837, Pl. 9) illustrated the features of the species, and it seems he used both specimens which are herein selected as neotype and paraneotype for his figures. For example, the anterior end and the branchiae match the neotype, whereas the complete specimen in dorsal view resembles the paraneotype.

De Quatrefages (1866: 388) regarded his C. incerta as very similar to C. flava (Pallas, 1766) and he followed Milne-Edwards (1837) figures, which were copied from those provided by Pallas (1766) in the original description. Because of the confusion between what de Quatrefages (1866) regarded as C. incerta de Quatrefages, 1866 (see below), and of its similarities with C. flava, Baird (1868: 231) proposed C. quatrefaguesii for those specimens included by de Quatrefages as C. flava from the Seas of China “without any of the synonyms quoted by him.”

Grube (1874: 326) questionably regarded his C. ceylonica as a variety of C. flava , and later he regarded it as a juvenile ( Grube 1878: 11), although he noted some differences between the specimens. Willey (1905: 244) confirmed that C. ceylonica is a junior synonym of C. flava .

Kinberg (1910, Pl. 11, Fig. 1G ) showed the complex inner structure of harpoon-chaetae, including a small spur over the opposite side of denticles. This feature was confirmed in the paraneotype, as indicated above.

M’Intosh (1885: 9) regarded C. pulchella Baird, 1868 as a synonym of C. flava without any detail about his conclusion. He might have thought that because the former was described with smaller specimens (44–45 mm long), against the larger ones used for describing C. flava (100 mm), then it could be possible that the middorsal oval spots in C. pulchella might become circular during development. This is not the case as shown below, because the largest specimens available (102 mm long, ZMA VPol 155) retain the oval middorsal spots. Ventrally bent specimens of C. flava show a distorted middorsal spot, from a circular to an oval shape, it must be emphasized that there are no size-dependent modifications for the middorsal spots. Consequently, as indicated below, C. pulchella is reinstated.

Several records did not include descriptions or illustrations, such that the specific identity cannot be confirmed ( Horst 1886, Moore 1903, Fauvel 1917, Ehlers 1920, Hoagland 1920, Treadwell 1920, Monro 1931, Monro 1934, Fauvel 1935, Holly 1935, Treadwell 1936, Fauvel 1937, Takahashi 1938, Fauvel 1939, Imajima & Hartman 1964, Imajima 2001, Imajima 2003). Some non-Indian Ocean records missing illustrations or other details can be confirmed after the study of several specimens. For example, Grube (1877: 509) for Salawatti and Amboina; Horst (1912: 18–19, Pl. 7, Fig. 2 ) for Indonesia.

Distribution. Bay of Bengal, Indian Ocean, to Australia, in sandy or sandy-mud substrates, in shallow water.

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 2. Chloeia viridis Schmarda, 1861, non-type specimens (BMNH 1931.6.22.16-18). A. Black form, anterior region, dorsal view. B. Same, chaetigers 10-12, dorsal view (branchiae removed from chaetiger 11). C. Same, posterior region, dorsal view. D. Red form, anterior region, dorsal view. E. Same, chaetigers 12-14, dorsal view (branchiae removed from chaetiger 13). F. Same, posterior region, dorsal view. Scale bars: A, F, 0.9 mm; B, E, 0.7 mm; C, 1 mm; D, 1.2 mm.

FIGURE 4. Chloeia fusca M’Intosh, 1885, non-type specimen (UF 4368). A. Ventral view. B. Ventral view after body wall removed. C. Same, after Methyl Green staining. D. Same, lower half of digestive tube removed. (AI, anterior intestine; MB, midventral band (nerve chord); MR, muscular ridge; Oe, oesophagus; PI, posterior intestine; R, rectum; St, stomach). All scale bars: 1 mm.

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 8. Chloeia amoureuxi sp. n., epitoke (MNHN 860.1). A. Anterior region, dorsal view. B. Anterior end, dorsal view. C. Anterior end, right lateral view. D. Posterior region. Scale bars: A, 1.8 mm; B, 0.5 mm; C, 0.6 mm; D, 1.5 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 19. Chloeia flava (Pallas, 1766), restricted, neotype (MNHN IA-TYPE 247). A. Dorsal view. B. Anterior end, dorsal view. C. Chaetigers 18-19, dorsal view (left branchia previously removed from chaetiger 19). D. Posterior end, dorsal view. Scale bars: A, 9.1 mm; B, 1.5 mm; C. 1.4 mm; D. 1.7 mm.

FIGURE 20. Chloeia flava (Pallas, 1766), restricted, paraneotype (MNHN IA-TYPE 252). A. Dorsal view. B. Anterior end, dorsal view. C. Chaetigers 13-19, dorsal view. Chaetae of neotype (left) and paraneotype (right); D. Chaetiger 3, notochaetae. E. Same, neurochaetae. F. Chaetiger 15, harpoon notochaetal tips. G. Same, neurochaetal tips. H. Paraneotype, posterior region, dorsal view. Scale bars: A, 4 mm; B, 0.8 mm; C. 1.7 mm; D, F, 50 μm; E, 25 μm; G, 40 μm; H, 2.1 mm.

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.