Chloeia slapcinskyi, Salazar-Vallejo, 2023

Salazar-Vallejo, Sergio I., 2023, Revision of Chloeia Savigny in Lamarck, 1818 (Annelida, Amphinomidae), Zootaxa 5238 (1), pp. 1-134 : 109-110

Chloeia slapcinskyi sp. n.

urn:lsid:zoobank.org:act:89C0D1D1-4A1D-43F5-B1FA-D1036C5E8C08

Fig. 51

Type material. The Philippines. Holotype ( UF 4353 ), Oriental Mindoro Province, Mindoro, Puerto Galera, Batangas Channel , "School Beach" (13.51688, 120.95983; 13°31´00.768″ N, 120°57´35.388″ E), 7–14 m, lagoon sand slope with sponges, 8 Apr. 2015, G. Paulay, coll. Two paratypes ( UF 4296 ), Luzon Island , Calatagan , off Lago de Oro Hotel , night dive house reef, the Deep Blue (13.91763, 120.6039; 13°55´03.468″ N, 120°36´14.04″ E), 8–12 m, sand flat and patch reef, 17 May 2014, G. Paulay & D. Uyeno, coll. (one complete, the other without posterior end; data in variation).

Diagnosis. Chloeia with bipinnate branchiae from chaetiger 4, decreasing in size posteriorly; middorsal bands short, not running along full segment; anterior eyes 4× larger than posterior ones; caruncle tapered with about 20 vertical folds; notochaetae furcates and harpoon chaetae with short tines; neurochaetae furcates with blunt tips.

Description. Holotype (UF 4353) complete, bent dorsally, left parapodia of chaetigers 11–14 removed for molecular analysis; body fusiform, 18 mm long, 3 mm wide, 23 chaetigers.

Holotype pale, chaetae transparent to yellowish, with darker subdistal areas; dorsal cirri dark purple; branchiae pale ( Fig. 51A ). Venter pale, midventral band wide, pale.

Prostomium anteriorly entire; anterior prostomial area blackish. Eyes brownish, anterior eyes 4× larger than posterior ones. Median antenna inserted at anterior caruncular margin, slightly longer than caruncle, 4× longer than lateral antennae. Lateral antennae bases separated from each other, slightly longer than palps. Mouth ventral on chaetiger 2. Pharynx partially exposed; basal rings pale, smooth, central paired lobes greenish ( Fig. 51B ).

Caruncle pale, sigmoid, trilobed, tapered, reaching chaetiger 5. Median ridge plicate, colorless, with about 20 vertical folds, partially concealing lateral lobes. Lateral lobes narrow, with about 18 vertical folds.

Bipinnate branchiae from chaetiger 5, parallel throughout body, progressively larger to chaetiger 11–12, about as long as 1.3 succesive segment, progressively smaller thereafter. Branchiae in median segments with 7–8 lateral branches.

Parapodia biramous, notopodia with cirriform branchiae along chaetigers 1–4, 1/3–1/4 as long as dorsal cirri. Dorsal cirri slightly longer than bipinnate branchiae along median chaetigers, 2–3× longer in posterior chaetigers. Second ventral cirri 2× longer than adjacent ones, as long as one subsequent segment medially and posteriorly.

Chaetae soft, most complete, distal hoods rarely eroded; noto- and neurochaetae of similar thickness. Notochaetae in anterior chaetigers furcates, some with golden major tines, major tines 3–4× longer than minor ones ( Fig. 50C ). Median chaetigers with three types of notochaetae ( Fig. 51E ): typical furcates with major tines usually 3–4× longer than minor ones, epitokal furcates with major tines about 12× longer than minor ones, and harpoon chaetae with denticulate tines 4–10× longer than smooth ones. Neurochaetae all furcates, anterior chaetigers with major tines 4–5× longer than minor ones ( Fig. 51D ); median chaetigers with major tines 4–6× longer than minor ones ( Fig. 51F ).

Posterior region tapered ( Fig. 51G ); pygidium with anus terminal; anal cirri pale, digitate, blunt, distorted, 3× longer than wide.

Etymology. This species is being named after Dr. John D. Slapcinsky, Malacology Collections Manager, in the University of Florida Natural History Museum, in recognition of his sampling efforts and support for my research activities. The specific epithet is a noun in the genitive case ( ICZN 1999, Art. 31.1.2).

Variation. Paratypes ( UF 4296 ) with many chaetae yellowish, a few colorless or reddish, especially along anterior region, most about as long as body width; dorsal cirri with cirrophores reddish; eyes red, anterior eyes 4× larger than posterior ones; median antenna longer than caruncle complete 21 mm long, 5 mm wide, 25 chaetigers .

Living pigmentation. Unknown, chaetae might have a more intense pigmentation with some banding of red and green, barely visible in early observations of the same specimens.

Remarks. Chloeia slapcinskyi sp. n. is described from The Philippines; by having bipinnate branchiae from chaetiger 5, and lacking dorsal pigmentation pattern, it belongs in the group longisetosa, together with C. longisetosa Potts, 1909 , described from the Maldive Islands, and C. wangi sp. n., described below from The Philippine Islands. Because of the presence of harpoon notochaetae, C. slapcinskyi resembles C. longisetosa . However, they differ in three main features: the size of median antenna to caruncle, chaetae to body width, and branchiae. Thus, C. slapcinskyi has its median antenna as long as, or longer than caruncle, its chaetae are as long as body width, and branchiae are as long as two successive segments, whereas in C. longisetosa the median antenna is shorter than caruncle, its chaetae are markedly longer than body width, and its branchiae are as long as one successive segment.

Distribution. The Philippines, in sediments at 7–14 m water depth.

Figures

FIGURE 50. Chloeia rosea Potts, 1909, holotype (BMNH 1924.3.1.145).A. Dorsal view. B. Anterior end, dorsal view. C. Chaetigers 6-8, dorsal view. D. Chaetiger 3, notochaetae. E. Same, neurochaetal tips. F. Chaetiger 15, notochaetae (insets: chaetal tips). G. Same, neurochaetal tips. Scale bars: A, 1.2 mm; B, 0.5 mm; C, 0.4 mm; D, 110 μm; E, G, 50 μm; F, 120 μm.

FIGURE 51. Chloeia slapcinskyi sp. n., holotype (UF 4353). A. Anterior region, dorsal view. B. Anterior region, left lateral view. C. Chaetiger 3, notochaetae. D. Same, neurochaetae (inset: neurochaetal tips). E. Chaetigers 13, notochaetae (inset: harpoon chaetae smooth tine). F. Same, neurochaetae (inset: neurochaeta tip). G. Posterior region, oblique dorsal view. Scale bars: A, B, 0.8 mm; C, E, 125 μm; D, F, 200 μm; G, 1 mm.