Hyalopale leslieae, Watson & Tilic & Rouse, 2019

Watson, Charlotte, Tilic, Ekin & Rouse, Greg W., 2019, Revision of Hyalopale (Chrysopetalidae; Phyllodocida; Annelida): an amphi-Atlantic Hyalopale bispinosa species complex and five new species from reefs of the Caribbean Sea and Indo-Pacific Oceans, Zootaxa 4671 (3), pp. 339-368 : 347-348

Hyalopale leslieae sp. nov.

urn:lsid:zoobank.org:act:C2DFADE6-6DFD-436E-9F30-418940CFE070

Figs 1C ; 3A ; 4 A–E

Material examined. Holotype. USNM 097530 , original designated paratype Hyalopale bispinosa by Perkins (1985), now identified as H. leslieae sp. nov. Florida Keys, Monroe County, Looe Key National Marine Sanctuary , reef crest, coralline covered rubble, less than 1m, 11E, L: 1.1mm, W: 0.75mm, gametes (? sperm) present .

Paratype, USNM 1490841 , same locality as holotype, 1, 10E, L: 0.75mm, W: 0.5mm,

Additional material. USNM 53171, Caribbean Sea, Bahamas, Bimini, Southern Bimini Lagoon, from plastic sponges submerged in lagoon, two anterior ends plus fragments, poor condition, coll. A. Schoener, 1970–71; LACM – AHF 2821, Caribbean Sea, British Virgin Islands, Guana Island, North Bay, 18° 28’909” N, 64° 34’485”W, dredged area inside inner reef, soft bottom of fine coralline sand & silt, with small rocks covered in turf algae & Sargassum , (eunicid tubes in sediment beneath rocks), 0.46m, coll. L. Harris, 12 Oct 1997, 1, 11E, L: 0.85mm, W: 0.6mm, gametes; LACM – AHF 2755, Guana island, White Bay, 18° 28’21” N, 64° 34’26” W, fine to medium calcareous sand off low energy beach next to rocky intertidal, filamentous algae over sand, 0.5m, 16 July 2001, 2E, fragments including anterior end with 8 segments, gametes present, W: 0.7mm; LACM – AHF 2827, Guana Island, White Bay, 18° 28’ 32” N, 64° 34’ 39”W, off rocky shore, from low green and calcareous mats scraped from surface of coarse sand at base of large rocks, 1.5m, coll. K. Fitzhugh, 21 July 2001, 1, 13E; LACM – AHF 2834; Beef Island, 18° 26’ 41” N, 64° 33’ 15” W, concrete ramp, off mangrove area, in Cladophora clump scraped off surface of concrete wall covered in turf algae (calcareous fragments interwoven with clump of tube dwelling maldanids, Scyphoproctus , terebellids), 0m, Oct 1997, coll. L. Harris, 1, 12E, L: 1.1mm, W: 0.65mm, gametes present; LACM – AHF 2829, Beef Island, 18° 26’ 41” N, 64° 33’.15 W, concrete ramp below bridge, calcareous algae on small rocks in soft bottom off mangrove, (clumps of Halimeda, Amphiroa scraped off dead coral sitting in soft sand/silt bottom, clumps heavily covered with tubes of tanaenids, maldanids (euclymenins and Scyphoproctus ), 0.3–0.6m, 15Oct 1997, coll. L. Harris, 1, 11E, L: 0.8mm, W: 0.55mm, gametes present; LACM – AHF 2756, West Beef Island near Hans Creek, on surface of living Pinctada sp. bivalve attached to severed mangrove root (covered with epifauna/ epiflora), 0.25m, 21 July 2000, coll. T. Haney, 1, 12E, sperm (?) present. Caribbean Sea, Belize, north tip of Carrie Bow Cay, 16.783° N, 88.067° W, September 2014, coll. G. Rouse, 1, 11E, specimen photographed at Scripps before being destroyed for DNA extraction and sequencing ( Fig. 4A ).

Diagnosis. Hyalopale with mid-body main paleae with sloping convex margin, (17) 18–20 (22) ribs, patchy, shallow raised ribs.

Description (based on holotype from Florida Keys). Pale body covered in glass-like notochaetal paleae with reflective shine; prostomium with two pairs of large red eyes, anterior pair melded; gametes present. Segment II notopodia with 3–4 spines each. Mid-body notochaetal fan comprises: lateral spine, 8–9 main paleae, single short midline spine. Lateral-most main paleae with 16/17 ribs, middle group paleae with (17)18–19 (20) ribs, shorter, slightly symmetrical midline-most main palea with 12/13 ribs ( Fig. 3A ). Main paleae with sloping convex margin, with very fine margin serration, inner margin with no visible serration, internal ribs densely packed, with 4–5 full length plus additional patchy shallow raised ribs, apices very small, blunt ( Fig. 1C ). Slender dorsal cirri just under half length of main fan. Mid-body neuropodia with falcigerous neurochaetae comprising: three superior long-blad- ed, two mid-superior long-bladed, 8–10 mid-group (some with longer basal blade serration), 6–8 inferior falcigers; slender ventral cirri under half-length to neuropodial tip. Paratype description same as holotype.

Additional description based on Belize specimen ( Fig. 4 A–D). Pale yellow body with shield-like white patches on anterior segments, green internal patches ( Fig. 4A ). Prostomium with two pairs of large eyes, notopodium of segment II with four simple spines; barrel-shaped pharynx, pair of stylets clearly visible ( Fig. 4C ). Mid-body notochaetal fan with single lateral spine, 8–9 main paleae, 1–2 short, curved midline spines ( Fig. 4E ). Main paleae with (16) 18–19 (22) ribs with ~ 3–4 shallow raised ribs and often multiple broken-line ribs; smaller lateral-most, midline-most main palea with 13–14 ribs ( Fig. 4D ). Pygidium with two anal cirri ( Fig. 4B ).

Remarks. Perkins (1985) considered the smaller material from the Florida Keys to be possible juveniles of Hyalopale bispinosa s.s. Re-examination of this material, including additional specimens from the Virgin Islands, showed that mature individuals were present, including ones with enlarged eyes and neurochaetae starting to denigrate. A lot of the latter material consisted of broken anterior ends, which prompted comparison of rib numbers in the main paleae of anterior ends between H. bispinosa s.s. and a possible new species. Comparison of these rib numbers of anterior notochaetae, and comparison where possible with those of mid-body notochaetae, showed consistent higher and lower paleal rib counts down the body between both morpho-species.

Characters defining the Florida Keys and Caribbean new species, in comparison with Hyalopale bispinosa s.s. are: smaller in length and number of segments (12E, 1.1mm L versus 20E, 2.8mm L); main paleae with consistent lower number of ribs (18/20 versus 26/28) with multiple raised shallow ribs versus no obvious raised ribs. The presence of gametes in conjunction with morphological differences indicates the material from Florida Keys and the Caribbean Sea represents a new species, Hyalopale leslieae sp. nov. The phylogenetic analyses ( Fig. 13 ) suggests that H. leslieae sp. nov., occupies a closer relation to Pacific taxa rather than the Mediterranean H. cf. bispinosa , though this node is poorly supported. It is of additional interest, that distributions of Hyalopale bispinosa s.s. and H. leslieae sp. nov. overlap in the Bahamas.

Etymology. Hyalopale leslieae sp. nov. is named in honour of Leslie Harris from the Los Angeles County Museum (LACM). Leslie is an indefagatible identifier and photographer of polychaetes who has over the years consistently bought chrysopetalids to the attention of CW, including the large amount of material from the Caribbean Virgin Islands, which characteristically includes beautifully detailed collection data.

Figures

FIGURE 1. Composite plate comparing notochaetal main paleae in Hyalopale species. A. Hyalopale bispinosa s.s. Florida, W. Atlantic; B. H. cf. bispinosa Crete, Mediterranean Sea; C. H. leslieae sp. nov. Florida Keys, W. Atlantic; D. H. furfuricula sp. nov. Mozambique, W. Indian Ocean; E. H. angeliensis sp. nov. Western Australia, E. Indian Ocean; F. H. zerofskii sp. nov. California, E. Pacific; G. H. sapphiriglancyorum sp. nov. E. Indonesia, W. Pacific. Note: correct number of raised and internal ribs figured.

FIGURE 3. Hyalopale leslieae sp. nov. Florida Keys, Paratype USNM1490841, chaetal types of right and part left mid-body notopodia; inset: midline-most main palea.

FIGURE 4. H. leslieae sp. nov. A–E Belize, micrographs, specimen photographed before sacrifice for DNA; A. live, dorsal view, entire body; B. pygidium with anal cirri; C. dorsal view, anterior end; D. lateral view, detail of main paleae & internal ribs; E. mid-body, notochaetal fan.

FIGURE 13. Maximum likelihood tree obtained with the molecular combined data (COI, 16S, 18S and H3) and with the hesionid Nereimyra punctata as outgroup. Values at nodes are shown as ML bootstrap then MP jackknife values. * =>90% values for ML bootstrap and MP jackknife values. The single MP tree was identical except that it recovered Paleanotus as the sistergroup to the remaining Chrysopetalinae, rather than to Hyalopale, though with only 53% jackknife support.