Edentellina babai, (Burn, 1965)

EdenTellina babai ( Burn, 1965)

( Figs 4M, N, 24A–C, 25–27)

Tamanovalva babai Burn 1965: 735–6 View in CoL , fig. 3. Type locality: Point Danger , Torquay, Victoria, Australia.

Type material

Tamanovalva babai , holotype, complete specimen, valves separated, damaged, 4.5 mm long ( MV F23064 ) .

Additional material examined

Harmers Haven , south of Wonthaggi, Victoria, Australia, 13 March 2008, one specimen 2 mm long (shell), on Caulerpa cactoides (Turner) C. Agardh, 1817 ( MV F159081 ) . Werribee , Port Philip, Victoria, Australia, 5 m depth, 11 December 1995, two specimens 3 mm long (shells), leg. CSIRO ( MV F112386 ) . Kity Miller Bay , Philip Island, Victoria, Australia, 13 February 2008, two specimens 3–3.2 mm long (shells) ( MV F158624 ) . Kingston , Norfolk Island, Australia, 1 March 1962,> 10 specimens 1.5–4.5 mm long (shells), leg. L. Marsh ( MV F22716 ) . Queensland, Australia, 9 October 2014, eight specimens 2–3 mm long (shells), leg. K. Kocot (lot 94-5E) . Lord Howe Island , Australia, one specimen ( AM C.469652) .

Description

Body elongate, ≤ 6.7 mm in length, completely retractable inside of shell. Body colour uniformly green, with a few minute white speckles concentrated on dorsal swelling near centre ( Fig. 24A– C). Head elongate, with eye spots located on dorsal swelling near centre. Rhinophores enrolled, green, with small white dots near tips. Oral tentacles short, green. Foot lighter than rest of animal. Mantle visible through shell, green, lacking other pigmentation. Foot forming small triangular projection, not extending beyond posterior end of shell.

Shell up to 4.5 mm × 3.3 mm in size, tallest point halfway between anterior margin and protoconch; widest point near ventral margin; shell shape ovoid, dorsal margin regularly curved, with a flatened expansion near anterior end, ventral margin more flattened; anterior margin convex, irregularly curved, slightly more flatened dorsally, posterior margin shorter, narrowing gradually ( Fig. 25G, H). Protoconch on lef valve of teleoconch, ~200 µm long, with 1.5 whorls ( Fig. 25K). Hinge on dorsal margin of shell, formed by flatened, corrugated, nearly straight area, margin on both valves; large, elongate condyloid tooth at posterior end of hinge on right valve, triangular, fossete-like hinge socket on lef valve, at posterior end of hinge ( Fig. 25I, J). Shell translucent, with no visible markings or spots on shell surface, sof parts of body visible through it ( Fig. 25A–F).

Adductor muscle slightly posterior to highest point of shell, in line with widest point ( Fig. 26A), connected to narrow and elongate head retractor muscle. Adductor scar visible on shell ( Fig. 25H). 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 below adductor muscle ( Fig. 26B), connecting to the pharyngeal bulb posteriorly ( Fig. 26C). Penis elongate; distal end pointed, with a short stylet ( Fig. 26E); proximal end wider, with strong retractor muscle and long, tubular deferent duct ( Fig. 26D).

Radula with 23 teeth in descending limb and 5 fully formed teeth + 1 ghost tooth in ascending limb, in 3-mm-long specimen from Victoria, Australia ( MV F112386 ) ( Fig. 27A), and 22 teeth in descending limb and 5 fully formed teeth + 1 ghost tooth in ascending limb, in 4.5-mm-long specimen from Queensland, Australia (lot 94-5E) ( Fig. 27D). Active tooth ~100–150 μm long ( Fig. 27B, E), with sharp, bifid or pointed tip; blade elongate, with central row of numerous elongate, delicate denticles; base short, curved. Ascus containing one long, rod-shaped pre-radular tooth and four or five intermediate teeth ( Fig. 27C, F) .

Biology

Burn (1989) indicated that T. babai feeds on Caulerpa scalpelliformis (R. Brown ex Turner) C. Agardh, 1817 , Caulerpa geminata Harvey, 1855 and C. cactoides (Turner) C. Agardh, 1817 .

Range

Southern and Eastern Australia, including Tasmania, Lord

Howe Island, and Norfolk Island ( Burn, 1965, 1989, 2015; present paper).

Remarks

Burn (1965) introduced the name Tamanovalva babai Burn, 1965 for specimens he previously identified as Edentellina typica (see remarks of E. typica ). According to Burn (1965), this species is characterized by having an ovatetrigonal shell with a large, vertically oriented protoconch, with 1.5 whorls. Burn (1965) described the live animals as green, with a green mantle visible through the shell, and the radula as having denticulate teeth with bifid apices. Burn (1989, 2015) illustrated a specimen from Philip Island, Victoria, which is green, with white spots all over the body but more concentrated in the rhinophores; the mantle is green, with numerous reddish-brown spots and white strings visible through the shell.

For this study, we examined several specimens from Victoria, Tasmania, and Lord Howe Island, Australia (some of them identified by R. Burn), matching the characteristics of the original description of T. babai , in addition to those of the holotype of this species ( Fig. 4M, N). Two specimens were sequenced successfully and are genetically distinct from other species of Juliidae , but nested with other species of Edentellina . Morphologically, T. babai is characterized by having an elongate penial stylet, similar to that of E. australis . For all these reasons, we consider T. babai a valid and distinct species, but it is transferred to the genus Edentellina .

EdenTellina waltairensis ( Sarma, 1975)

Berthelinia oaltairensis Sarma 1975: 20–21 , figs 23–27, 30. Type locality: Visakhapatnam , India.

Type material

Holotype and paratypes at the Department of Zoology , Andhra University, Waltair, India, not examined .

Remarks

Sarma (1975) described the new species Berthelinia oaltairensis Sarma, 1975 based on live specimens collected in Visakhapatnam, India. Te body of live animals was described as leaf-green, with the oral tentacles, rhinophores, and foot speckled with white, and the mantle dark green and visible through the shell ( Sarma 1975). Sarma (1975) illustrated the oval shell, with a round anterior end and narrower posterior end, with the highest point near the anterior end, and the protoconch posterior to mid-length. Sarma (1975) described the white protoconch as having 1.5 whorls, and the hinge with a strong anterior tooth and second weaker posterior tooth. Te radula had seven teeth in the ascending limb and 25 in the descending limb, teeth blade-like with simple tips, and fine denticulations on both sides ( Sarma 1975).

We have been unable to obtain specimens matching the original description of B. oaltairensis , which remains as an uncertain species. However, because of its morphological similarities to other species of Edentellina , it is here transferred to this genus.