Pollentia perezi Capa & Pons & Jaume 2022, SP. NOV.
Creators: name: Capa, María
name: Pons, Joan
name: Jaume, Damià
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Phyllodocida
Polynoidae
Pollentia
Pollentia perezi

description: POLLENTIA PEREZI SP. NOV.
(FIGS 3, 4, 5, 6)
Zoobank registration: urn: lsid: zoobank. org:act: DF4ED4DA-818A-49E0-9996-AFDB2FAD73FA
Type material: Cova des Bastons (also known as Cave C-11), Alcúdia, Mallorca, Balearic Islands, 39°53 ′ 03.1 ″ N, 3°11 ′ 45.1 ″ E. Holotype: specimen preserved in ethanol; collected by J. Pérez at 17 m depth on bare rock with some patches of calcareous silt, 11 March 2020 (MNCN 16.01 /18955) (Supporting Information Video S 15). Paratype: specimen preserved in ethanol, divided into two fragments, same collector, locality, substratum and depth, 30 June 2019 (MNCN 16.01 /18956).
Additional material examined: specimen preserved in RNAlater, same collector, locality, substratum and depth as holotype (deposited at IMEDEA collection) (see Supporting Information Video S16).
Description of holotype: Body length 18 mm, maximum width 6 mm at midbody segments (including parapodia;
*A pair of large eyes was described in Bathymoorea renotubulata by Pettibone (1967) and in Bathymoorea lucasi by Bonifácio & Menot (2019), but these are considered herein as potential misinterpretations.
excluding chaetae). Body 27-segmented, flattened dorsoventrally, anterior margin blunt, tapering posteriorly (Fig. 4). Specimen pale when alive, with some tiny brown spots scattered over dorsum, forming narrow segmental transverse bands near base of notopodia and elytrophores, and on ventrum near base of parapodia (Figs 4, 5C, D). Head intensely coloured dark red (pigmented brain visible through translucent epithelium; Figs 4A, C, D, 5A–C).
Prostomium bilobed, wider than long, with lobes extending anteriorly to form ceratophores of lateral antennae (Figs 5A–C, 6A). Median antenna inserted proximal to anterior margin of prostomium; ceratophore bulbous, longer than wide (Figs 5B, 6A); style tapering, reaching segment 3 (Fig. 5B). Lateral antennae with styles also tapering, shorter than median antenna (Fig. 5A, B). Median and lateral antennae with scattered long papillae on styles (Fig. 6A–C). Palps stout and longer than antennae, reaching segment 6, heavily wrinkled and covered with minute oval papillae (Figs 4D, 5A, 6B, E, F). Eyes absent (Figs 4A, C, D, 5A–C).
Tentacular segment (segment 1) with short lobe inserted lateral to prostomium; aciculae not penetrating epidermis; bundle of about six notochaetae (Figs 5A, C, 6B, H). One pair of tentacular cirri present on each side of segment; tentaculophores longer than wide, ventral larger than dorsal (Fig. 6H); tentacular styles tapering, dorsal and ventral of similar length, reaching segment 5 (Fig. 4D); styles covered with elongated papillae (Fig. 6I). Mouth lips strongly developed, protruding when pharynx not everted (Fig. 5E). Facial tubercle absent, but slightly inflated longitudinal ridge present on upper lip (Fig. 6B, G). Pharynx not everted in holotype and dissected in paratype, with ring of elongate, blunt subconical papillae of similar size (Fig. 6M, not counted) and two pairs of jaws with smooth margins (Fig. 6N). Segment 2 devoid of nuchal pads and folds (Fig. 6A–C).
Thirteen pairs of elytra, one on each of segments 2, 4, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23 and 26. Elytra large, covering dorsum, lacking papillae, each with microtubercles along external edge (Fig. 7A–D) and on dorsal surface of posterior third (Fig. 7E). Surface of anterior part of elytra smooth (Fig. 7F). Dorsal cirri present on non-elytrigerous segments from segment 3 onwards; cirrophores cylindrical (Fig. 8A–C); styles elongated and tapering, largely surpassing length of parapodia and chaetae, of similar length (Figs 4C, D, 8F, H), with some long, scattered papillae. Dorsal tubercles inconspicuous, low and conical, more evident on elytrigerous segments (Fig. 8B).
Segment 2 with subbirramous parapodia, enlarged conical acicular lobe, and noto- and neurochaetae (Fig. 6H). Ventral cirri of segment 2 (buccal cirri) inserted basally, with large cirrophores; stylode longer than subsequent counterparts, with elongated papillae (Fig. 6I). Rest of segments also with subbiramous parapodia and with thin and long, tapering acicular lobes projecting on both rami; notoacicular lobe shorter than neuroacicular and hidden under the inferior notochaetae (Fig. 8B); neuroacicular lobe conspicuous (Fig. 8E, G); noto- and neuroaciculae not penetrating into lobes (Fig. 8D, E, G). Notopodia rounded, one-third the length of neuropodium; latter subconical, with further indistinct lobes other than the acicular projections (Fig. 8E–G). Ventral cirri inserted at midlength of neuropodia (Fig. 8E–G), with short ceratophore and smooth, tapering style reaching about midlength of parapodia (Fig. 8A, B). Styles of ventral cirri of segments 2 and 3 longer than subsequent counterparts, with elongated papillae (Fig. 8H–K); styles from segment 4 onwards all similar in length, without papillae (Fig. 8I, L). Semispherical papillae ventrally at base of parapodia (Fig. 8M).
Notochaetae of all segments similar, of only one type (~20 on parapodia of anterior and midbody segments), stouter than neurochaetae, arranged in dense, radiating tufts (Fig. 9A, B). Notochaetae smooth and straight basally, slightly curved and tapering, with welldeveloped spinous rows along convex margin (Fig. 9 A-C) and pointed, conical tips. Two types of neurochaetae (30–40 on parapodia of midbody segments) arranged in transverse rows. Superior neurochaetae flattened, with one side bearing faintly spinous rows (Fig. 9 D-F); tip tridentate, with a slightly hooked tooth and two additional smaller teeth (Fig. 9F). Inferior neurochaetae shorter and thinner than superior counterparts, each with a cylindrical proximal half and a broader, lanceolate and flattened distal half; one of sides with well-developed spinous rows reaching the tip (Fig. 9G, H).
Unpigmented nephridial papillae present at base of parapodia from segment 5 onwards, small and bulbous. Nephridial papillae from segment 8 onwards connect to posterior half of body through long ducts, visible under light microscopy. Pygidium small, rounded, not enclosed by last segment (Fig. 5G), with anus placed terminally. Pair of anal cirri longer than dorsal cirri.
segment number. Intraspecific variability: Paratype, with 26 segments, measuring 18 mm long (including tentacular segment) and maximum width 6 mm at midbody segments (including parapodia; excluding chaetae). Pigmentation pattern similar to holotype (Figs 4, 5). Specimen with most elytra detached after preservation. Most other morphological features as for holotype (Figs 4, 5).
Ecology: The first specimen was found and collected after scuba divers accidentally dropped an object on the sandy bottom of the cave and the animal escaped from danger, ascending to the water column (Supporting Information Videos S 15, S16). The other two specimens were each found in subsequent visits to the cave, crawling on the sediment. In all cases, specimens were found at 17 m depth in full-strength marine water (38 PSU) at 19 °C (Fig. 1C).
Etymology: Species named after the Mallorcan cave diver Joan Pérez, who discovered the species and kindly offered the material to us for study.
Remarks: The new Mallorcan cave polynoid bears an overall resemblance to members of the subfamily Eulagiscinae, in that they all share the terminal or subterminal insertion of the lateral antennae on anterior extensions of the prostomium, and the parapodia display notopodia shorter than neuropodia, unlike members of other related subfamilies (Wehe, 2006; Bonifácio & Menot, 2019). However, there are some morphological features that are unique among the current members of Eulagiscinae. The number of pairs of elytra, 13 in Pollentia perezi, is the lowest reported in the subfamily (Table 5; Pettibone, 1967, 1997; Bonifácio & Menot, 2019). In addition, the chaetal morphology and arrangement in Pollentia perezi are unique amongst members of Eulagiscinae and even Polynoidae. Thus, body segments from segment 2 onwards bear only stout notochaetae with spinous rows and pointed tips, similar to those described in Eulagisca and Bathymoorea lucasi (Table 5). Neurochaetae are of two types: the superior flattened, spinous and with a tridentate tip, whereas the inferior are shorter and thinner, lanceolate, spinous and tapering (Table 5). Furthermore, the superior neurochaetae are unique amongst those of Polynoidae, because they have a tridentate tip, with a main larger tooth and two additional smaller teeth. The inferior neurochaetae resemble the pectinate forms described in members of Eulepethidae (Pettibone, 1969).
Both Eulagisca and Paraeulagisca are oculate (each bearing two pairs of eyes). The two nominal species of deep-sea Bathymoorea were described as bearing a pair of large eyes, but we consider this to be a misinterpretation of the brain occupying most of the prostomial lobes, as in the anchialine Pollentia perezi, which is eyeless. Like its deep-sea relatives, Pollentia perezi lacks body pigmentation except for a few scattered spots distributed as described above.
description: Published as part of Capa, María, Pons, Joan & Jaume, Damià, 2022, Discovery of a new scale worm (Annelida: Polynoidae) with presumed deep-sea affinities from an anchialine cave in the Balearic Islands (western Mediterranean), pp. 479-502 in Zoological Journal of the Linnean Society 196 on pages 490-498, DOI: 10.1093/zoolinnean/zlac046, http://zenodo.org/record/7035469