Edentellina pseudochloris, (Kap, 1964)

McCarthy-Taylor, Jennifer B., Krug, Patrick J., Muro, Sandra, Vendeti, Jann, Maestrati, Philippe, Wong, Nur Leena W. S., Gosliner, Terrence M. & Valdés, Ángel, 2025, Te slug within the bivalve: molecular and morphological systematics of the family Juliidae (Gastropoda: Panpulmonata: Sacoglossa), Zoological Journal of the Linnean Society 204 (2) : -

EdenTellina pseudochloris (Kap, 1964)

( Figs 4G, H, L, 5I–L, 21–23) Berthelinia pseudochloris Kay 1964: 191–193 , fig. 1, pl. 9, figs 1, 4. Type locality: Near Koloa Landing, Koloa, Kaua‘i, Hawaiian Islands.

Tamanovalva fijiensis Burn 1966: 54–55 , pls. 15–19. Type locality: Nukulau Island , Viti Levu, Fiji.

Berthelinia ganapatii Sarma 1975: 16–20 , figs 6–13, 28, 29.

Type locality: Visakhapatnam , India .

Type material

Berthelinia pseudochloris , holotype, complete specimen, not examined ( BM 8903 ). Paratype, one complete specimen, 3.7 mm long (shell) ( CASIZ 018374 ) .

Tamanovalva fijiensis , holotype, complete specimen, shell dissolved, 1.5 mm long (animal) ( MV F25647 ) .

Berthelinia ganapatii , holotype and paratypes at the Department of Zoology , Andhra University, Waltair, India, not examined .

Additional material examined

Central Pacific and Haoaiian Islands: Honokowai Beach Park , Maui , Hawaiian Islands , 2–11 m depth, 9 October 2010, one specimen 4.5 mm long (shell), isolate JC21 ( CASIZ 185144 ). Mama’s Fish House Tide Pool, Maui, Hawaiian Islands, tissue only, isolate Bpse16Mau06. Olivine Pools, Maui, Hawaiian Islands, 15 June 2011, one specimen 3 mm long (shell), isolate JC11B ( CPIC 00315 ) .

Western Pacific: East of Santa Cruz Island , off Zamboanga, Mindanao, Philippines, 9–18m depth, 19 January 1981, one valve 4 mm long, leg. J. M. McLean ( NHMLA 1981 - 71.7 ) . Mabini , Luzon, Philippines, 2001, one specimen 5 mm long (shell), isolate JC33B ( CASIZ 199470 ) . Momo Beach , Panglao Island, Philippines, 28–32 m depth, 10 June 2004, one valve 4 mm long, leg. Panglao Marine Biodiversity Project, stn. S8 ( MNHN) . Pamilacan Island , Philippines, 6–8 m depth, 14 June 2004, one specimen (dry) 2.8 mm long, leg. Panglao Marine Biodiversity Project, stn. S12 ( MNHN) . Bingag , Panglao Island, Philippines, 20 m depth, 17 June 2004, one specimen 4 mm long, leg. Panglao Marine Biodiversity Project, stn. B16 ( MNHN) . South Megas Islet , Madang, Papua New Guinea, 6 m depth, 14 November 2012, one valve 4.1 mm long, leg. Expédition Papua Niugini, stn. PS12 ( MNHM) . Between Kranet Island and Paeowa Island, Madang, Papua New Guinea, 2–10 m depth, 27 November 2012, one valve 4.5 mm long, leg. Expédition Papua Niugini, stn. PD52 ( MNHM) . South Urembo Island , Madang, Papua New Guinea, 10 m depth, 5 December 2012, one valve 4.5 mm long, leg. Expédition Papua Niugini, stn. PS41 ( MNHM) . North Riwo , Madang, Papua New Guinea, 3 m depth, 13 December 2012, one valve 2.3 mm long, leg. Expédition Papua Niugini, stn. PB53 ( MNHM) . Northwest point of Nusa Island, Kavieng Lagoon, Madang, Papua New Guinea, 3 June 2014, one specimen 5.1 mm long (shell), leg. Expédition Kavieng 2014, stn. KB03 ( MNHN IM-2013-47177 ) . Northwest point of Manne Island, Kavieng Lagoon, Madang, Papua New Guinea, 4 June 2014, one specimen 3.1 mm long (shell), leg. Expédition Kavieng 2014, stn. KB06 ( MNHN IM-2013-47623 ) . Malokilikili , Espiritu Santo, Vanuatu, 7 m depth, 5 October 2006, one specimen (dry) 4.9 mm long, leg. Santo Marine Biodiversity Survey, stn. FB52 ( MNHN) . Segond Channel , Wambu River mouth, Espiritu Santo, Vanuatu, 7 m depth, 6 October 2006, one valve 4 mm long, leg. Santo Marine Biodiversity Survey, stn. DS91 ( MNHN) . North Tutuba Island , Espiritu Santo, Vanuatu, 17–19 m depth, 11 October 2006, three valves 3–4.5 mm long, leg. Santo Marine Biodiversity Survey, stn. DS101 ( MNHN) . West Tutuba Island , Espiritu Santo, Vanuatu, 70–80 m depth, 14 October 2006, one valve 4 mm long, leg. Santo Marine Biodiversity Survey, stn. DS103 ( MNHN) . Off north of Urélapa Island, Espiritu Santo, Vanuatu, 100 m depth, 14 October 2006, one valve 4 mm long, leg. Santo Marine Biodiversity Survey, stn. EP32 ( MNHN) . Tutuba Island , Vanatovoa Bay, Espiritu Santo, Vanuatu, 2–4 m depth, 14 October 2006, one specimen (dry) 2.1 mm long, leg. Santo Marine Biodiversity Survey, stn. FB92 ( MNHN) . Bruat Channel , North coast of Malo Island, Espiritu Santo, Vanuatu, 35 m depth, 19 October 2006, one valve 4 mm long, leg. Santo Marine Biodiversity Survey, stn. DS110 ( MNHN) . Grand Récif Mengalia , Secteur Touho, New Caledonia, September 1993, one specimen (dry) 2.2 mm long, leg. Expédition Montrouzier, stn. 1245 ( MNHN) . Banc de Touho , Secteur de Touho, New Caledonia, Sep 1993, one specimen (dry) + four valves 2–4 mm long, leg. Expédition Montrouzier, stn. 1259 ( MNHN) . Grand Récif Mengalia , Secteur de Touho, New Caledonia, 10–35 m depth, September 1993, three valves 3.5–5 mm long, leg. Expédition Montrouzier, stn. 1270 ( NHMN) . Tié shoal, Secteur de Touho, New Caledonia, 5–25 m depth, October 1993, one specimen (dry) + three valves 2–3.5 mm long, leg. Expédition Montrouzier, stn. 1271 ( NHMN) . Récif Extérieur , Passe de Touho, Secteur de Touho, New Caledonia, 20 m depth, September 1993, two valves 4 mm long, leg. Expédition Montrouzier, stn. 1273 ( NHMN) . Baie de Koumac , Secteur Koumac, New Caledonia, 3–7 m depth, October 1993, one valve 6.5 mm long, leg. Expédition Montrouzier, stn. 1297 ( MNHN) . Grand Récif de Koumac , Secteur Koumac, New Caledonia, 12 m depth, October 1993, eight valves 2.1–3.9 mm long, leg. Expédition Montrouzier, stn. 1316 ( MNHN) . Passe Deverd , Secteur de Koumac, New Caledonia, 15–20 m depth, October 1993, one specimen (dry) 3.5 mm long, leg. Expédition Montrouzier, stn. 1319 ( MNHN) . Lansdowne , west of New Caledonia, 427–505 m depth, 20 October 2005, one specimen (dry) 3 mm long, leg. Campagne Ebisco, stn. DW2617 ( MNHN) . Lizard Island , Australia, 13 July 2006, one specimen, sequence only (Tl 792LIC) .

Indian Ocean : Ponta do Farol , Inhaca Island, Mozambique, 27 November 2011, one specimen (dry) 4.5 mm long, leg. Expédition Inhaca, stn. MM6 ( MNHN) .

Description

Body elongate, ≤ 8.5 mm in length, completely retractable inside of shell. Body colour vibrant dark green, with a few scatered white speckles ( Fig. 5I–L). Head elongate, with eyespots located on dorsal swelling near centre. Rhinophores enrolled, green, with small white speckles ofen concentrated at the apex. Oral tentacles short, green. Foot lighter than rest of animal. Mantle visible through shell, vibrant dark green, covered with small white dots; edge surrounded by conspicuous alternating opaque white patches composed of densely arranged speckles. Foot extending to posterior end of shell, forming small triangular projection.

Shell up to 6.5 mm × 4.6 mm in size, tallest point near anterior end, widest point near ventral margin; shell shape ovoid, dorsal margin with flatened extension near anterior end, ventral margin more flatened; anterior margin convex, irregularly curved, slightly more flatened dorsally, posterior margin narrowing gradually, forming a nearly triangular, elongate shape, with round end ( Fig. 21G, H). Protoconch on lef valve of teleoconch, ~215 µm long, with 1.5 whorls ( Fig. 21K). Hinge on dorsal margin of shell, formed by flatened, corrugated, nearly straight area, margin on both valves; small, oval condyloid tooth on right valve at posterior end of hinge, and triangular, fossete-like hinge socket on lef valve, at posterior end of hinge ( Fig. 21I, J). Shell translucent, with no visible markings or spots on shell surface, sof parts of body visible through it ( Fig. 21A–F).

Adductor muscle located closer to anterior end of shell, in line with widest point ( Fig. 22A, C), connected to narrow and elongate head retractor muscle. Adductor scar visible on shell ( Fig. 21H). Gill large, occupying almost height of body, posterior to adductor muscle, covering anterior portion of digestive gland. Anterior half of body in preserved specimens with pair of elongate pharyngeal appendages visible anterior or dorsal to adductor muscle, connecting to the pharyngeal bulb posteriorly ( Fig. 21B). Penis elongate; distal end pointed, with a cuticularized tip; proximal end wider, with two strong retractor muscles atached ( Fig. 21D).

Radula with 33 teeth in descending limb and 5 fully formed teeth in ascending limb, in 5.1-mm-long specimen from Papua New Guinea (MNHN IM-2013-47177) ( Fig. 23A), and 31 teeth in descending limb and 5 fully formed teeth + 1 ghost teeth in ascending limb, in 4.5-mm-long specimen from Maui, Hawaiian Islands (CASIZ 185144). Active tooth ~90–130 μm long, with sharp, pointed tip; blade elongate, with central row of numerous long, delicate denticles; base short, curved ( Fig. 23B, D). Ascus spirally coiled, with one long, rod-shaped pre-radular tooth, plus several (more than five) intermediate teeth ( Fig. 23C).

Biology

Kay (1964) reported that Berthelinia pseudochloris occurs on dense masses of Caulerpa racemosa var. turbinata [= Caulerpa chemnitzia ] with litle intrusion of other algal species, in areas with constant and frequently heavy surf. Burn (1966) reported collecting B. fijiensis on Caulerpa racemosa var. turbinata [= Caulerpa chemnitzia ]. Sarma (1975) found Berthelinia ganapatii fairly commonly on the Visakhapatnam foreshore during the period from December to May among Caulerpa racemosa . Sarma (1975) described the egg masses and development of B. ganapatii ; the number of eggs in egg masses fluctuated from 500 to 3520, with eggs 50 µm in diameter and capsules 90 µm, indicating that this species is probably planktotrophic (see Krug et al. 2015). Both C. racemosa and C. chemnitzia are closely related species and members of the C. racemosa –peltata complex (see Belton et al. 2014).

Range

Hawaiian Islands ( Kay 1964; present paper), Japan ( Ono 1999), Fiji ( Burn 1966), Philippines (present paper), Papua New Guinea (present paper), Vanuatu (present paper), New Caledonia (present paper), India (Prabhakara Rao 1965, Ganapati and Sarma 1972, Sarma 1975), Madagascar ( Legendre 1965), Mozambique (present paper), Réunion ( Joannot and Vendel 2011), South Africa ( Gosliner 1987), and possibly, Easter Island ( Rehder 1980).

Remarks

Kay (1962a) reported a single specimen of a live bivalved sacoglossan collected in the Hawaiian Islands. Kay (1962a) argued that this animal was morphologically different from other species described to date and probably constituted a distinct species. Kay (1964) formally described the species as Berthelinia pseudochloris Kay, 1964 , based on several specimens collected Near Koloa Landing, Kaua‘i, Hawaiian Islands. Kay (1964) described the shell of this species as small, thin, translucent green, ovate-triangular, rounded anteriorly, narrower posteriorly, with the white protoconch on the lef valve, and the hinge with a strong tooth, and frequently a secondary weaker tooth posteriorly. Te live animals, subsequently illustrated by Kay (1979), were described as leaf-green, with minute opaque milk-white spots on the oral tentacles, rhinophores, and foot; rhinophores with one or two larger white blotches, head and neck are microscopically speckled with brown, mantle with red bands alternating with white patches, visible through the shell ventrally ( Kay 1964). We examined several specimens from the Hawaiian Islands matching the characteristics enumerated in the original description of B. pseudochloris , in addition to the shell morphology of the paratype ( Fig. 4G, H); these animals are anatomically and genetically distinct from other species here examined and constitute a distinct species. Terefore, we here regard B. pseudochloris as a valid species. Additionally, geometric morphometrics and molecular analyses of specimens here examined from the Hawaiian Islands confirm that this species is distinct and a member of the Recent genus Edentellina .

Burn (1966) introduced Tamanovalva fijiensis Burn, 1966 based on a single specimen collected from Viti Levu, Fiji. Te live holotype was described as pale green, with cream speckling on the slender, auriculate, and abruptly truncate rhinophores ( Burn 1966). Te characteristics of the paleyellow shell included a steeply angled and rather straight anterior margin, a broadly rounded posterior margin, and a small, white protoconch, slightly inclined to the lef, anterior to the second third of the shell length. According to Burn (1966), the radula had five teeth in the ascending limb and 25–30 in the descending limbs; radular teeth rather stout, strongly rounded above the simple tip and laterally finely denticulate. Burn (1966) placed this species in Tamanovalva because of having one and a half whorls, not two, in the protoconch. Burn (1966) recognized that the holotype of T. fijiensis had a similar shell outline to that of E. pseudochloris (see Kay 1964: fig. 4; Burn 1966: figs 15, 16). Also, both feed on Caulerpa chemnitzia , have a white protoconch with 1.5 whorls, and have short and wide radular teeth with numerous denticles ( Fig. 23; Burn 1966: fig. 18). Given these similarities, we propose that T. fijiensis is a synonym of E. pseudochloris . A photograph of the holotype of T. fijiensis included here ( Fig. 4L) confirms the morphological similarities to E. pseudochloris .

Sarma (1975) described Berthelinia ganapatii Sarma, 1975 based on live specimens collected in Visakhapatnam, India. Te colour of the rhinophores, neck, and foot were described as uniformly yellow, with the tips of the rhinophores speckled with white spots ( Sarma 1975); the mantle was deep yellowish-green, with two bright shining yellow patches, all visible through the transparent shell. Sarma (1975) described the shell as deep green but transparent [sic.], with yellow rays on the surface, fragile, ovate trigonal in outline, with the anterior margin rounded and abrupt, and the posterior margin longer. Te small, erect protoconch was situated at the third quarter of the shell length, and the hinge had a weak tooth in the lef valve and a strong tooth posteriorly on the right valve. Sarma (1975) described the radula as having blade-like teeth bearing fine denticulations on the sides and having simple tips, with seven teeth in the ascending row and 35 in the descending row. Sarma (1975) recognized that B. ganapatii was close to E. pseudochloris but distinguishable by having a more abrupt anterior margin, a longer posterior margin, and an erect protoconch. Similarities between these two species are remarkable: they both feed exclusively on species of the C. racemosa –peltata complex; they have a hinge with teeth, and fairly similar external coloration. Te radula of B. ganapatii contains short and broad teeth with numerous denticles ( Sarma 1975: fig. 13), very similar to the teeth of E. pseudochloris here illustrated ( Fig. 23). Finally, both species have planktotrophic development. Because of the similarities between the original descriptions of B. ganapatii and B. pseudochloris , we regard these two names as synonyms.

Records of Berthelinia spp. from several localities in the Indo-Pacific region, including Madagascar ( Legendre 1965), India (Prabhakara Rao 1965, Ganapati and Sarma 1972), South Africa ( Gosliner 1987), and tropical Japan ( Ono 1999) were based on animals very similar to the specimens of E. pseudochloris here examined and are here regarded as members of this species. A record of E. pseudochloris from Easter Island by Rehder (1980) could not be verified with certainty.