Chloeia inermis de Quatrefages, 1866

Salazar-Vallejo, Sergio I., 2023, Revision of Chloeia Savigny in Lamarck, 1818 (Annelida, Amphinomidae), Zootaxa 5238 (1), pp. 1-134 : 75-77

Chloeia inermis de Quatrefages, 1866

Figs 33 , 34

Chloeia inermis de Quatrefages, 1866: 389 ; Baird 1868: 232; Benham 1915: 206–207; Augener 1924: 258–259; Benham 1916: 390–391, Figs 6–11 (descr.); Benham 1927: 84–85 (size variation; syn.); Monro 1936: 80; Knox 1960: 80; Hartman 1959: 131; Barroso & Paiva 2011: 422, Tab. 1; Read 2011: 101, 3 unnumb. figs.

Chloeia spectabilis Baird, 1868: 234 .

Chloeia australis Kudenov, 1993: 99–100 , Figs 3 , 6 ; Barroso & Paiva 2011: 422, Tab. 1.

Type material. New Zealand. Holotype of Chloeia inermis de Quatrefages, 1866 ( MNHN IA-TYPE 95), J.R.C. Quoy & J.P. Gaimard, coll. (no further data; Oct. – Dec. 1826 after Dumont d’Urville 1830: 113 & following pp; type not listed by Solís-Weiss et al. 2004). Holotype of C. spectabilis Baird, 1868 ( BMNH 53.4.7.7), Capt. Stokes, coll., no further data (left neuropodium, of chaetiger 9 and left notopodium of chaetiger 14 previously removed; other data used for variation). Paratype of C. australis Kudenov, 1993 ( USNM 139106), USNS Eltanin, Sta. 368 (43°16´S, 175°23´E to 43°21´S, 175°22´E), 84 m, 19 Nov. 1966 (data used for variation).

Additional material. New Zealand. One specimen ( BMNH 1928.2.29.171 ), British Antarctic Terra Nova Expedition , Sta. 134, Spirits Bay, near North Cape , shelly bottom, 20–36 m, 31 Aug. 1911 (pale, including branchiae; median antenna 4/5 as long as caruncle; dorsal cirri purple; pharynx exposed, rings smooth; bipinnate branchiae from chaetiger 5; some parapodia previously removed; dorsal cirri dark purple; branchiae from chaetiger 5; body bent ventrally, 15 mm long, 4.5 mm wide, 24 chaetigers). One specimen ( BMNH 1936.2.8.20 ), RRS Discovery II, Sta. 939 (35°49.6´S, 173°27´E to 35°51.6´S, 173°28.9´E), 87 m, 18 Aug. 1932 (juvenile; pale, fusiform, several parapodia previously removed; anterior eyes 2–3× larger than posterior ones; body bent ventrally 9 mm long, 2.5 mm wide, 23 chaetigers). One specimen ( ZMH V9448 ), Colville Channel , Auckland, T. Mortensen, coll. (slightly bent ventrally, colorless; dorsal cirri dark purple, cirrophores darker; 28 mm long, 7 mm wide, 28 chaetigers) . Australia. One specimen ( AM E5225 ), FIS Endeavour 1909–1910, Sta. not specified, Tasmania, off South Cape (43°38' S, 146°42' E), 135 m (data used for variation) .

Diagnosis. Chloeia with bipinnate branchiae from chaetiger 5, progressively smaller posteriorly, stems basally pale; notochaetae spurred and acicular, rarely harpoon chaetae without spurs; neurochaetae acicular and spurred.

Description.

Holotype of C. inermis ( MNHN IA-TYPE 95) complete, many notochaetae broken ( Fig. 33A ); body fusiform, slightly bent ventrally, tapered in both ends, posterior end distorted by compression; 34 mm long, 10 mm wide, 33 chaetigers.

Holotype homogeneously pale after ca. 200 years in ethanol ( Fig. 33B ), chaetae yellowish; some median and posterior segments with violet dorsal cirrophores; venter pale.

Prostomium anteriorly entire. Eyes blackish, anterior eyes 3–4× larger than posterior ones. Median antenna inserted at anterior caruncular margin, twisted, 2/3 as long as caruncle ( Fig. 33C ), 2× longer than lateral antennae. Lateral antennae bases close to each other, slightly longer than palps. Mouth ventral on chaetigers 2–3. Pharynx barely exposed, pale.

Caruncle pale, tapered, curved to the left, trilobed, reaching chaetiger 4. Median ridge plicate, with about 27 vertical folds, partially concealing right lateral lobe. Lateral lobes narrow, with about 24 vertical folds.

Bipinnate branchiae from chaetiger 5, continued throughout body, parallel throughout body; progressively larg-er to chaetiger 10, smaller in last 10 chaetigers. Median segments with 10–12 lateral branches.

Parapodia biramous, notopodia with cirriform branchiae along chaetigers 1–4, damaged, shorter than dorsal cirri. Dorsal cirri longer than bipinnate branchiae along median chaetigers and 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 variable broken, hoods mostly eroded, especially notochaetae, most neurochaetae complete. Complete chaetae with distal fragile hoods, most eroded completely. Notochaetae in all chaetigers acicular, smooth, without furcates; a very few harpoon chaetae with minute denticles ( Fig. 33D ). Neurochaetae aciculars, smooth ( Fig. 33E ).

Posterior region tapered; pygidium with anus terminal; anal cirri bent dorsally, pale, digitate, 4–5× longer than wide.

Live pigmentation (after Dav (2015), Morris (2010) and Marriott (2022)). Body with dorsum pink, with a middorsal whitish longitudinal band; caruncular median ridge whitish; branchiae reddish; dorsal cirri dark purple or blackish.

Variation. The holotype of C. spectabilis (BMNH 53.4.7.7) is pale, barely fusiform ( Fig. 34A ); its anterior eyes are 3× larger than posterior ones. Its median antenna is broken. The caruncle is twisted, pale, reaching chaetiger 3. Cirriform branchiae along chaetigers 1–4. Bipinnate branchiae from chaetiger 5, without cirriform branchiae. Cirrostyles distally pigmented along few anterior and posterior chaetigers ( Fig. 34B ); venter with abundant surface whitish disks; body bent ventrally; body 57 mm long, 10 mm wide, 32 chaetigers. Harpoon chaetae not found. Posterior region tapered ( Fig. 34C ); anal cirri digitate, whitish, about 4 longer than wide. The paratype of C. australis (USNM 139106) is an epitoke; pigmentation pattern reduced to purple dorsal cirri, often only cirrostyles purple; its anterior eyes almost 3× larger than posterior ones. Its median antenna is as long as caruncle. The caruncle is contracted, appears smooth, tapered, reaching chaetiger 3. Cirriform branchiae in chaetigers 1 and 2, other ones lost. Bipinnate branchiae from chaetiger 5, without cirriform branchiae. Harpoon-chaetae not found, most notochaetae acicular, but anterior and posterior neuropodia with long natatory spurred capillaries. Body slightly bent ventrally, 53 mm long, 13 mm wide, 34 chaetigers. Another specimen (AM E5225) is included because it was studied by Benham; body bent laterally; colorless ( Fig. 34D ); anterior eyes slightly larger than posterior ones; branchiae from chaetiger 5; anterior chaetigers with spurred notochaetae ( Fig. 34E ) and neurochaetae ( Fig. 34F ), spurs barely visible; median chaetigers with acicular notochaetae ( Fig. 34G ), and neurochaetae, spurs not visible ( Fig. 34H ); body 42 mm long, 10 mm wide, 28 chaetigers.

Remarks. Chloeia inermis de Quatrefages, 1866 , originally described from New Zealand, it resembles species in the group longisetosa by having bipinnate branchiae from chaetiger 5, but it differs from those species by having a white middorsal longitudinal band. In the key above, it resembles C. wangi sp. n., described below from The Philippines because harpoon notochaetae are rare to nill in median segments. However, these species differ in three features: the size of its median antenna to caruncle, basal pigmentation of bipinnate branchial stems, and type of notochaetae. Thus, in C. inermis the median antenna is shorter than caruncle, its branchial stems do not have basal spots, and notochaetae are spurred or aciculars, whereas C. wangi has a median antenna as long as caruncle, its branchial stems have a basal white spot, and notochaetae are furcates (major tines 3–4× longer than minor ones).

The specific epithet selected by de Quatrefages (1866: 389, Latin diagnosis; 388) refers to the presence of smooth chaetae, instead of being denticulate (Latin inermis , e: unarmed, without spines), as indicated by Benham (1916: 390). However, there are a few harpoon notochaetae in the damaged holotype of C. inermis , but most notochaetae are acicular.

De Quatrefages also indicated his new species could be identical to C. egena Grube, 1855 , described with a damaged specimen, without locality, that has been regarded as indeterminable (see above). In the description of C. spectabilis, Baird (1868: 231 , 234) indicated that it resembled C. inermis de Quatrefages, 1866 and C. egena Grube, 1855 , and that C. spectabilis “differs from both in minor details” but he did not indicate what the differences were. The holotype of C. spectabilis has no relevant differences with the holotype of C. inermis , thus becoming synonyms.

Horst (1910: 172) regarded the three above species as indeterminable. Benham (1915, 1916), Augener (1924), McIntosh (1925: 18), and Monro (1936) provided more details for recognizing C. inermis as distinct, besides having chaetae without serrations and with tips entire, sometimes with tiny spurs; for the pigmentation pattern they noted there is a middorsal paler band, purple median antennae and dorsal cirri, and branchiae from chaetiger 5. These features are present in the types of C. inermis and C. spectabilis , but the former has priority.

Kudenov (1993: 100) described C. australis from the Campbell Plateau (500 km South off New Zealand); the specific name was selected to emphasize the southern, subantarctic distribution of the species. His description detailed a dorsal surface with a middorsal pale longitudinal stripe, that notochaetae were smooth, and branchiae begin in chaetiger 5. Kudenov (2020 in email) indicated his species is a junior synonym of C. inermis de Quatrefages, 1866 . After the study of one of his paratypes, his synonymy proposal is herein confirmed. Kudenov (1993: 100) noted the abundant, long capillary neurochaetae with tiny spurs which would indicate the specimens having them are prenatatory epitokes.

Distribution. Australia to New Zealand, Chatham Islands, Chatham Rise, Campbell Plateau, west of Antipodes and Bounty islands, in sediments at 20–183 m depth ( Kudenov 1993: 100).

Figures

FIGURE 3. Chloeia mezianei sp. n., non-type specimen (NHMD 915074). A. Left lateral view. B. Anterior end and pharynx, seen from above. C. Same, right lateral view. Scale bars: A, 1 mm; B, 0.6 mm, C, 0.5 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 33. Chloeia inermis de Quatrefages, 1866, holotype (MNHN IA-TYPE 95). Dorsal view. B. Anterior región, dorsal view. C. Anterior end, after Methyl green staining. D. Chaetiger 18, notochaetal tips. E. Same, neurochaetal tips. Scale bars: A, 2.4 mm; B, 1.6 mm; C, 1.3 mm; D, 100 μm; E, 150 μm.

FIGURE 34. Chloeia inermis de Quatrefages, 1866. A. Holotype of C. spectabilis Baird, 1868 (BMNH 53.4.7.7), anterior region, dorsal view. B. Same, anterior end, dorsal view. C. Same, posterior region, dorsal view. D. Non-type specimen (AM E5225), anterior end, dorsal view, after Methyl green staining. E. Same, chaetiger 3, notochaetae (inset: tip). F. Same, neurochaetal tips. G. Chaetiger 14, notochaetae. H. Same, neurochaetal tips. Scale bars:A, 2.2 mm; B, C, 1.3 mm; D, 0.8 mm; E, 150 μm; F, 30 μm; G, 250 μm; H, 25 μm.