Loimia brasiliensis, Carrerette, Orlemir & Nogueira, João Miguel De Matos, 2015

Carrerette, Orlemir & Nogueira, João Miguel De Matos, 2015, The genus Loimia Malmgren, 1866 (Annelida: Terebellidae) off the Brazilian coast, with description of three new species and notes on some morphological characters of the genus, Zootaxa 3999 (1), pp. 1-31 : 22-30

Loimia brasiliensis sp. nov.

( Figures 10–14 ; Table 4)

Loimia medusa . — Blankensteyn 1988: 58 –61, fig. 12.

Type series. Holotype MZUSP 0 2372 and paratype 1 MZUSP 02373: Praia de Jaguaribe (7°43'31.50"S 34°49'33.04"W, intertidal, 11.Dec.2012). Paratypes 2 MZUSP 0 2374, paratype 7 ZUEC 16672, paratype 8 ZUEC 16673 and paratype 9 AM W. 47669: Baía da Traição, Ponta da Prainha (6º41'19"S 34º55'48"W, intertidal, 09.Aug.2010). Paratype 3 MZUSP 0 2375, and paratype 6 ZUEC 16671: Rio Tinto, Barra de Mamanguape (6º46'8"S 34º55'1"W, intertidal, 11.Aug.2010). Paratype 4 USNM 1273440, and paratype 5 1273441: Barra de Camaratuba (6º36'11"S 34º57'52"W, intertidal, 12.Aug.2010). Paratype 10 AM W. 47670: Praia de Tabatinga (7º16'40"S 34º47'54"W, intertidal, 10.Feb.2009).

Material examined. Project ‘BioPol–NE’: State of Paraíba: Mataraca, Barra de Camaratuba: 6°36'11"S 34°57'52"W, intertidal, 6 specs, 12.Aug.2010. Rio Tinto, Barra de Mamanguape: 6°46'8"S 34°55'1"W, intertidal, 3 specs, 11.Aug.2010. Baía da Traição, Ponta da Prainha: 6°41'19"S 34°55'48"W, intertidal, 9 specs, 09.Aug.2010. João Pessoa, Praia de Cabo Branco: 7°8'48"S 34°47'46"W, intertidal, 1 spec., 02.Feb.2010. Conde, Praia de Jacumã: 7°16'40"S 34°47'54"W, intertidal, 4 specs, 29.Jan.2010; Praia de Tabatinga: 7°16'40"S 34°47'54"W, intertidal, 2 specs, 10.Feb.2009. State of Pernambuco: Itamaracá, Recifes de Itamaracá: 7°46'3"S 34°49'27"W, 2–3 m, 2 specs, 15.Dec.2012; Praia de Jaguaribe: 7°43'31"S 34°49'33"W, intertidal, 8 specs, 11.Dec.2012. Goiana, Praia de Pontas de Pedra: 7°37'43"S 34°48'28"W, intertidal, 4 specs, 13.Dez.2012. São José da Coroa Grande: 8°54'2"S 35°8'13"W, intertidal, 1 spec., 25.Jun.2013. Ipojuca, Praia de Muro Alto: 8°25'59"S 34°58'39"W, 2 specs, 17.Jan.2014. Project Habitats: State of Rio de Janeiro, Campos Basin: 21°10'11"S 40°46'4"W, 21 m, 1 esp., 22.Jul.2009; 22°1'4"S 40°32'1"W, 49 m, 1 esp., 24.Jul.2009. State of São Paulo: São Sebastião, Praia do Araçá: 23°52'S 45°27'W, intertidal, 6 specs, 13.Aug.2012.

Additional material examined for comparison. Loimia grubei sensu Blankensteyn (1988) — ZUEC 6131 (coll. 24°53'00"S 46°46'07"W, 47 m, 1 spec.); ZUEC 6043 (coll. 24°16'00"S 46°01'02"W, 50 m, 1 spec.); L. medusa sensu Blankensteyn (1988) — ZUEC 6044 (coll. 26°29'05"S 48°21'04"W, 38 m, 1 spec.). Loimia bandera Hutchings, 1990 : holotype, AM W.201924 (coll. 6 km S.S.E off Port Island, New Territories, 24 m, S/edge, coll. 5.Apr.1986); paratypes AM W.201926–7 (coll. Hong Kong, Tap Mun, 22°29'N 114°22'E, Apr.1986). Loimia batilla Hutchings & Glasby, 1988 : holotype, AM W.5162 (coll. Moreton Bay, 20°26'S 147°05'E, Queensland, Australia, coll. 1971); paratype AM W.7097 (coll. Middle Banks off Tangalooma, 27°12'S 153°21'E, Queensland, Australia, coll. 1972); paratype AM W.7106 (coll. Middle Banks off Tangalooma, 27°12'S 153°21'E, Queensland, Australia, coll. 1972); paratype AM W.7107 (coll. Moreton Bay, 20°26'S 147°05'E, Queensland, Australia, coll. 1970). Loimia triloba Hutchings & Glasby, 1988 : paratype AM W. 200558 (coll. Australia, Queensland, Low Isles, Great Barrier Reef, 16°23'S 145°34'E). Loimia medusa (Savigny in Lamark, 1818): neotype, LACM-AHF Poly 1656 (coll. Upper Persian Gulf, coll. Tetra Tech, Apr.1982, shallow shelf).

Description. Anteriorly expanded worms, progressively tapering from midbody, coiled after notopodia terminate ( Figs 10 A–F; 11A–F; 13A–C). Complete specimens with 43–89 (89) segments, 4.9–45 (45) mm long, 0.8–3.2 (3.2) mm wide (Table 4). Body yellowish to light green in life specimens, with darker, yellow mid-ventral shields ( Fig. 10 A–D); preserved body whitish, without distinct patterns of pigmentation, except for light brown transverse bands along buccal tentacles ( Fig. 11 A–F). Prostomium at base of dorsal side of upper lip; basal part of prostomium with 2 rows of eyespots, concentrated laterally, distal part forming shelf-like process from which long, cylindrical buccal tentacles originate ( Figs 10 A–E, 11A–F; 13B, C, E, G–H). Peristomium restricted to lips; expanded upper lip, nearly circular; lower lip short, button-like to rectangular, partially hidden by lobes of segment 1 ( Figs 10 A, C–D; 11A–B; 13A–H). Segment 1 not conspicuous dorsally, only visible by large, paired lobes, originating ventro-laterally, with oblique dorsal margins aligned with ventral edges of neuropodia; lobes distally rounded, higher ventro-laterally, reaching around 2/3 of length of upper lip ( Figs 10 A–B; 11A–F; 13A). Segment 2 conspicuous dorsal and laterally, partially hidden by lobes of segment 3, ventrally fused to segment 3 ( Figs 10 A–E; 11A–B, D–E; 13A–C, E–H); segment 3 longer than previous ones, with pair of relatively low, almost semicircular lobes, distally rounded, barely covering base of lobes of segment 1; lobes with base narrower than tip, originating dorso-laterally, aligned to base of notopodia of segment 4, terminating ventro-laterally, aligned to ventral edges of neuropodia, with narrow gap to fused mid-ventral shield of segments 2–3; dorsal edges of lobes pointed, with tip extending dorsally in relation to base, reaching level of notopodia, terminating far from bases of branchiae ( Figs 10 A–D; 11A–F, 13A–F); segment 4 conspicuous all around, with mid-ventral shield partially fused to that of segments 2–3 mid-ventrally, lobes absent ( Figs 10 A–E; 11A–F, 13A–C, F–H); following anterior segments about same size until segment 8, then progressively longer ( Figs 10 A–E; 11A–E; 13A–C). Three pairs of branching branchiae on segments 2–4, with short basal stem, pairs of branchiae progressively shorter, all longitudinally aligned, or first pair slightly ventral to remaining pairs ( Figs 10 B, E; 11A–F; 13A–B). Rectangular, smooth to slightly crenulate, swollen mid-ventral shields on segments 2 to 14–15 (14), partially fused on segments 2–4, progressively narrower and more indented by neuropodia posteriorly from segment 5 to last shield, last 2–3 shields, on segments 13–15, divided by 2–3 transverse lines, more evident in live specimens due to bright blood red pigmentation ( Fig. 10 A–C); from segment 15–16, shields replaced by mid-ventral groove extending posteriorly. Cylindrical, short notopodia, on segments 4–20, bearing narrowly-winged chaetae in both rows, those from posterior row about twice as long as those from anterior row, with wings on distal half only ( Figs 12 A–D; 14A). Neuropodia beginning from segment 5, as low rectangular ridges slightly raised from surface of body until segment on which notopodia terminate, as elongate, prominent pinnules thereafter ( Figs10 A–D, F; 11A–B, D–F; 13A–C, H); neuropodia bearing uncini in double rows on segments 11–20, ventral edges of neuropodia progressively closer to ventral mid-line until termination of notopodia, with ventral edges progressively closer to each other within pairs; double rows of uncini completely separate from each other to partially intercalating crests on ventral edges of tori, uncini in back-to-back to crest-to-crest arrangement ( Figs 12 G; 13I; 14D, F). Uncini pectinate, higher than long, with concave base, short triangular heel directed backwards, prow downwardly directed, aligned with line of teeth, connected to long filament; uncini throughout with 5 progressively shorter teeth, sometimes a few uncini with 6 teeth scattered along tori; basal tooth distinctly larger ( Figs 12 E–J; 13I; 14B–J). Genital papillae at base of notopodia of the segments 6–8 ( Fig. 10 B), rarely visible; some specimens with mass of gametes on anterior segments. Anus surrounded by crown of short, digitiform papillae ( Fig. 10 F).

Remarks. Three species of Loimia resemble L. brasiliensis sp. nov., in having uncini with 5–6 teeth, L. bandera , L. batilla and L. medusa (see Table 2). However, all these species have mid-ventral shields extending to segment 12, while in L. brasiliensis sp. nov., they continue to segment 14–15. In addition, L. bandera and L. batilla differ from L. brasiliensis sp. nov., by having distal part of prostomium as V-shaped crest, in not having eyespots at basal part of prostomium, in having lobes of segment 1 extending dorsally, originating at level of first pair of branchiae, and uncini with short teeth, all about same size. In contrast, L. brasiliensis sp. nov., has the distal part of prostomium forming shelf-like process, the basal part of prostomium with 2 rows of eyespots, concentrated laterally, as well as paired lobes of segment 1 originating ventro-laterally, with oblique dorsal margins aligned to ventral edges of neuropodia, and uncini with progressively shorter teeth distalwards, from main fang to tip of uncini (see Table 2).

Loimia medusa , as already discussed, had previously been considered as a cosmopolitan species until Hutchings and Glasby (1995) designated and described a neotype for the species, and suggested it has a distribution restricted to the Arabian Sea region. Londoño-Mesa and Carrera-Parra (2005) identified Mexican specimens as L. medusa and, as they could not find any substantial difference between their specimens and the description of the neotype provided by Hutchings and Glasby (1995), they suggested L. medusa could be a complex of sibling species. Subsequently Londoño-Mesa and Carrera-Parra (2005) and later Londoño-Mesa (2009), resurrected two species of Loimia from the Caribbean Sea, which had previously been synonymized with L. medusa , L. minuta and L. bermudensis .

TABLE 4. Morphological variation within the type-series of Loimia brasiliensis sp. nov.

Holotype Paratype 1 Paratype 2 Paratype 3 Paratype 4 Paratype 5 Paratype 6 Paratype 7 Paratype 8 Paratype 9 Paratype 10 ( MZUSP ( MZUSP ( MZUSP ( MZUSP ( USNM ( USNM ( ZUEC ( ZUEC ( ZUEC (AM (AM 02372) 02373) 02374) 02375) 1273440) 1273441) 16671) 16672) 16673) W.47669) W.47670)

(length x 45 x 3.2 23.1 x 3.2 12 x 1.0 30 x 1.0 18.2 x 2.0 13 x 1.9 11 x 1.2 11.7 x 1.2 4.9 x 0.9 6.1 x 0.8 5.5 x 0.9 width (mm))

Number of 89 84 57 49 44 54 49 29 43 49 51 segments

Eyespots Present Present Present Present Present Present Present Present Present Present Present

Ventral 14, 2 last 15, 2 last 15, 2 last 14, 2 last 15, 2 last 14, 2 last 15, 2 last 15, 2 last 14, 2 last 14, 2 last 14, 2 last shields segments segments segments segments segments segments segments segments segments segments segments segments) divided into 2 divided into 2 divided into 2 divided into 2 divided into 2 divided into 2 divided into 2 divided into 2 divided into 2 divided into 2 divided into 2 or more or more or more or more or more or more or more or more or more or more or more

transverse transverse transverse transverse transverse transverse transverse transverse transverse transverse transverse lines lines lines lines lines lines lines lines lines lines lines

Genital 6 – 8 – – Not visible Not visible; Not visible; Not visible Not visible; Not visible Not visible Not visible; papillae with mass of with mass of with mass of with mass of segments) gametes on gametes on gametes on gametes on anterior anterior anterior anterior

segments segments segments segments

Number of 5 x 5 5 x 5–6 5 x 5 5 x 5 5 x 5 5 x 5–6 5 x 5–6 5 x 5 5 x 5 5 x 5 5 x 5 teeth: anterior

posterior

uncini

Loimia medusa was widely recorded along the Brazilian coast, first by Nonato and Luna (1970) and subsequently by several others (see in Amaral et al. 2013). Loimia medusa resembles L. brasiliensis sp. nov., in having lateral eyespots and in the morphology of both anterior pairs of lobes, those of segments 1 and 3; it differs, however, by having ventral shields extending until segment 12, and anterior uncini with 4 teeth, while in L. brasiliensis sp. nov., shields extend to segment 14 and uncini throughout have 5 teeth, sometimes 6 in a few uncini mixed with others with 5 teeth, along tori of a few specimens.

Etymology. We attribute to this taxon the epithet “ brasiliensis ” in reference to this taxon being the species of Loimia most frequently found along the Brazilian coast.

Type locality: States of Pernambuco, Praia de Jaguaribe (7°43'31.50"S 34°49'33.04"W).

Distribution: States of Paraíba, Pernambuco, Rio de Janeiro and São Paulo

Figures

FIGURE 10. Loimia brasiliensis sp. nov. (Holotype, MZUSP 0 2372, alive): (A). Complete animal, ventro-lateral view; (B). Anterior part, lateral view; (C). Anterior part, ventral view; (D). Detail of the anterior part, lobes of segments 1 and 3, ventral view; (E). Anterior part, dorsal view; (F). Detail of the pygidium. Numbers refer to segments; ul = upper lip. Scale bars: A, D = 500 Μm; B – C, F = 200 Μm; E = 100 Μm.

FIGURE 11. Loimia brasiliensis sp. nov. (Holotype, MZUSP 02372): (A – B). Anterior part, ventral views; (B). Anterior part, ventral view; (C). Anterior part, dorsal view; (D). Anterior part, right lateral view; (E). Anterior part, left lateral view; (F). Detail of the anterior part, dorsal view. Numbers refer to segments; II = lower lip; P = distal part of prostomium; ul = upper lip * = basal part of prostomium. Scale bars: A = 1 mm; B – F = 0.5 mm.

FIGURE 12. Loimia brasiliensis sp. nov. (Holotype, MZUSP 02372): (A). Notochaetae, segment 5; (B). Notochaetae, segment 15; (C). Notochaetae, segment 19; (D). Notochaetae, segment 9; (E). Uncini, segment 6; (F). Uncini, segment 8; (G). Uncini, segment 19, double rows of uncini; (H). Uncini, segment 22; (I). Uncini, segment 31; (J). Uncini, segment 31. Scale bars: A = 80 Μm; B = 30 Μm; C, E – F = 20 Μm; D, H, J = 40 Μm; G, I = 10 Μm.

FIGURE 13. Loimia brasiliensis sp. nov. (Paratype, MZUSP 02375): (A). Anterior part, ventral view; (B). Anterior part, lateral view; (C). Detail of the anterior segments, lobes on segments 1 and 3, lateral view; (D). Detail of the oral region, ventral view; (E). Detail of the prostomium, dorsal view; (F). Detail of the anterior segments, lobes on segments 1 and 3, ventral view; (G). Detail of the anterior segments, dorsal view; (H). Detail of the anterior segments, lobes on segments 1 and 3, lateral view; I, detail of posterior neuropodia. Numbers refer to segments; II = lower lip; P = prostomium; ul = upper lip. Scale bars: A = 200 µm; B – C = 100 µm; D – F = 50 µm; I = 20 µm

FIGURE 14. Loimia brasiliensis sp. nov. (Paratype, MZUSP 02375): (A). Notopodium from anterior segments; (B). Neuropodium from the anterior part; (C). Detail of the uncini from an anterior segment; (D). Uncini from segment 12, double rows of uncini; (E). Detail of uncini from segment 14; (F). Detail of uncini from segment 19; (G). Detail of uncini from segment 22; (H). Detail of uncini from segment 31; (I). Detail of uncini from segment 15; (J). Detail of uncini from segment 34. Scale bars: A = 20 µm; B – C, F, H = 5 µm; D = 8 µm; E, G, I = 2 µm.