Chloeia euglochis Ehlers 1887
Creators: name: Yáñez-Rivera, Beatriz
name: Salazar-Vallejo, Sergio I.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Amphinomida
Amphinomidae
Chloeia
Chloeia euglochis

description: Chloeia euglochis Ehlers, 1887 reinstated
Figs 1A, 4, 5C–F
Chloeia euglochis Ehlers, 1887: 18–24, Pl. 1, Figs 1, 2; Pl. 2, Figs 1–8; Pl. 3, Figs 1–4; Haeckel 1904: Pl. 96, Fig. 7; Augener 1906: 96; Hartman 1938: 6.
Chloeia modesta Ehlers, 1887: 21–24, Pl. 2, Figs 6–8, Pl. 3, Fig. 3 (juveniles).
Chloeia viridis: Augener 1925: 20–21; Hartman 1951: 29; Borda et al. 2012: 310 (sequences); 312 (phyl. aff.) (partim, non Schmarda, 1861).
Chloeia sp. Humann et al. 2013: 85 (alive specimens).
Type material. Florida. Syntypes of Chloeia euglochis. [MCZ ANNa 617] Tortugas (24°39'54.5436" N, 82°51'19.4328" W), Apr. 1881, A. Agassiz & Fewkes, coll. [MCZ ANNa-664] W off Tortugas, 16 Jan. 1869, no further data. [MCZ ANNa 720] Tortugas, no further data (2). [MCZ ANNb-1252] Off French Reef, 81 m, 3 Apr. 1869, L.F. Pourtalès, coll. [MCZ ANNc-2240] no data. Syntypes of Chloeia modesta. [MCZ ANNa-869] off Marquesas Keys, 18-27 m, 10 Feb. 1869, L.F. Pourtalès, coll. (2). [MCZ ANNa-1097] off French Reef (in label: off Marquesas Keys in catalogue), 221 m, 21 Mar. 1869, L.F. Pourtalès, coll.
Additional material. Florida.[MCZANNa-3](26°29'45.2940"N, 82°43'30.3528"W);1854-1858,Wurdemann, coll. [UF 83] Off Fort Pierce (27°04'46.3800" N, 80°00'27.7200" W), 11 Jan. 2003 (1). [UF 478] Florida Straits, SSW of Dry Tortugas Keys (24°27'20.9999" N, 83°11'17.9999" W), 113-121 m, 10 May 2006, Snelson, F. coll. (1). [UF 682] Palm Beach, Peanut Island, shoal N of island, 4 Mar. 2008, G. Paulay, coll. (1). [UF 687] Palm Beach, Peanut Island, shoal N of island, 4 Mar. 2008, G. Paulay, coll. (1). [UF 1912] off Jacksonville (30°29'37.4640" N, 81°18'50.0400" W), 30 Mar. 2010, 18 m, Bemis, M. & Moore, J., coll. (1). [UF 1926] south of Saint-Petersburg (26°16'53.4000" N, 82°43'07.3200" W), 32 m, 7 Mar. 2011, G. Paulay, M. Bemis, J. Moore, coll. [UF 4308] West Palm Beach, Blue Heron, 7 Jan. 2015; Uyeno & Daisuke, coll. (2). [UF 4350] West Palm Beach, Blue Heron Bridge (26°46'59.1600" N, 80°02'29.4000" W), 21 Mar. 2015, Moore, J. & Walker, W. (10).
Diagnosis. Chloeia with ventral cirri of similar size throughout body; bipinnate branchiae from chaetiger 4; dorsum with a pigmented cross per segment, made by wide bands throughout body; chaetal bundles with a wide reddish band.
Description. Largest syntype (MCZ ANNa-720) complete, 99 mm long, 23 mm wide, 35 chaetigers. Body fusiform; dorsal pigmentation pattern visible (Fig. 4A, D), resembling living pattern (Fig. 1A). Each segment with irregular brown-orange transverse bars wider in the middle, like a cross with widened endings. Cirrophores of dorsal cirri violet. Chaetae with orange and yellow bands (better retained in another syntype, Fig. 4D). Live color pattern includes one pair of bright white to yellowish spots in each cross interspaced and on the dorsal side of branchiae (Fig. 1A). Mouth ventral on chaetiger 3.
Prostomium semicircular with four black eyes; anterior eyes 3× larger than posterior ones. Antennae and palps pale; median antenna longer than paired antennae and palps. Caruncle narrow, median lobe elevated with about 15 folds. Lateral basal lobes narrow. Branchiae start in chaetiger 4. Parapodia biramous. Notopodia with cirriform branchiae along chaetigers 1–3.
Neurochaetae furcates long or short. Smaller tine very short, like a spur, even some chaetae lack it appearing spurred, with a basal remnant (Fig. 4E–G). Notochaetae serrated, harpoon type (Fig. 4E).
Pharynx fully exposed in a non-type specimen (UF 1912; 92 mm long, 18 mm wide, 36 chaetigers); pillowlike, 16 mm long 13 mm wide, separated into two large cushions; basal cushion 2–4 mm long, with a basal smooth surface, and two muscular ridges; proximal ridge partially covered by distal ridge, middorsally incomplete by a shallow depression; distal cushion with dorsal surface smooth, mouth opening as a wide U-shaped depression; lateral and ventral surfaces with 30–32 transverse thin ridges, progressively shorter towards mouth opening.
Juveniles. Notochaetae of small juvenile (10 mm long) specimen with reddish pigmentation along most of their length (Fig. 5C), and the dorsal cross is defined (Fig. 5D). The middorsal pigment bands are expanded laterally in the anterior of the body with two lateral thin branches, and the convergent bands becoming widened medially reaching the middorsal band, approaching the cross pattern seen in adults, including the paler areas surrounding it. Progressively larger juveniles have a reddish (Fig. 5E) or greenish pigmentation (Fig. 5F), but the basic crosspattern is retained, and the basic coloration extends along the anterior surface of notopodia.
Another smallest juvenile (UF 1926; 4 mm long, 2 mm wide, 16 chaetigers) is colorless. Anterior eyes 3× larger than posteriors; median antennae 2× longer than laterals; caruncle conical, tapered, straight, reaching chaetiger 4, lateral lobes barely projected; dorsal cirri almost as long as body width; branchiae start in chaetiger 4, but on the left side with an additional cirriform branchiae. Mouth in chaetiger 3, ventral cirri of chaetiger 2 is 2× longer than those present in adjacent chaetigers (1, 3), of similar length as those in chaetigers 4–10.
Remarks. Chloeia euglochis Ehlers, 1887 has been regarded as a junior synonym of C. viridis Schmarda, 1861. Augener (1925: 20–21) studied the type material of C. viridis. He noted it was 29 mm long and that the dorsum had a violet-brownish longitudinal middorsal band, more or less T-shaped in each segment, and that the chaetae were homogeneously pale. This slight pigmentation made him think C. viridis should be a paler juvenile of the colorful C. euglochis, and that C. modesta Ehlers, 1887, also described with small (12–16 mm long) colorless specimens, should also be juveniles. Ehlers informally named the latter species, although in the illustrations he indicated the smaller specimens were juvenile C. euglochis.
We think Augener was correct by regarding C. modesta as a junior synonym of C. euglochis, and this synonymy was originally considered by Ehlers (1887: 21). However, we think Augener was not correct by regarding C. viridis and C. euglochis as synonyms, especially because of the pigmentation pattern, and the presence of short bifid neurochaetae. For C. euglochis, its pigmentation pattern was diagnosed as having a deep red cross per segment, chaetae with reddish pigmentation, and no short bifid neurochaetae. For C. viridis, pigmentation pattern was described as a T-shaped dark brown longitudinal band, chaetae were not banded, and short neurochaetae were clearly bifid. This pigmentation was confirmed for C. viridis by Augener (1925) about 70 years after its original description, whereas for C. euglochis the dorsal reddish cross is still visible in type specimens about 150 years after its collection. Regretfully, Augener’s (1925) conclusion was followed by Monro (1933) and subsequent researchers. We hypothesize that Augener ideas might have been influenced by Haeckel’s plate (Fig. 3C), where green was rather freely incorporated into Ehlers’ original color plate.Although green variants of C. euglochis have been noted through some photos available in internet, the typical dorsal cross is visible, and this differs from the single, longitudinal dark band shown by C. viridis.
Furthermore, the study of some small juveniles of C. euglochis from Florida (UF 4308, UF 4350) allowed us to confirm that reddish notochaetae appear in specimens about 10 mm long, and that the dorsal cross pattern starts to become developed by then. This means that specimens of C. euglochis even one-third as long as the type of C. viridis, already show the diagnostic dorsal cross, and reddish notochaetae and neurochaetae. Consequently, this long-standing synonymy must be rejected, and C. euglochis Ehlers, 1887 is herein reinstated.
Thus, C. euglochis was considered as a junior synonym of C. viridis after Monro (1933) and Hartman (1938). Monro considered that the difference in pigmentation pattern was a “color-variant” of C. viridis (Monro 1933: 9). In the same publication, he mentioned an erroneous pigmentation pattern of C. viridis with three bands. When Harman (1938: 6) reviewed the syntype of C. euglochis [MCZ 617.664.720], she considered that it was identical to C. viridis according to Monro’s description. However, the pigmentation pattern illustrated by Monro is different from the one present in C. euglochis, which has a cross mark on each segment while C. viridis has only a single band.
The syntype illustrated here (Fig. 3A) is the same reviewed by Hartman and the pigmentation pattern is perfectly consistent with the illustration included in the original description by Ehlers (1887). Other morphological features used to regard C. euglochis as a junior synonym of C. viridis were that branchiae start in the same chaetiger, and both have violet cirri. Nevertheless, the dorsal cirri of C. euglochis have violet pigmentation only in the cirrophore, whereas the start of branchiae in chaetiger 4 is shared by several Chloeia species (Table 1).
Both pigmentation patterns in cross mark and the chaetal features are distinctive for C. euglochis, since none of the other species present a spurred neurochaetae. Ehlers (1887) provided a precise description of the dorsal pigmentation pattern, which was overlooked by subsequent taxonomists probably due to the prevalent confusion and emphasis on generic attributes.
One of the specimens (UF 83) had just ingested another member of the same species before being preserved; the ingested specimen has some reddish banded chaetae, as seen after the fracture of the body wall.
Distribution. Grand Caribbean region, in shallow water sediments (1–121 m depth).
description: Published as part of Yáñez-Rivera, Beatriz & Salazar-Vallejo, Sergio I., 2022, Revision of Chloeia Savigny in Lamarck, 1818 from tropical American seas (Annelida, Amphinomidae), pp. 503-537 in Zootaxa 5128 (4) on pages 512-516, DOI: 10.11646/zootaxa.5128.4.3, http://zenodo.org/record/6479987