Hypselodoris paradisa, Gosliner & Johnson, 2018

Epstein, Hannah E., Hallas, Joshua M., Johnson, Rebecca Fay, Lopez, Alessandra & Gosliner, Terrence M., 2018, Reading between the lines: revealing cryptic species diversity and colour patterns in Hypselodoris nudibranchs (Mollusca: Heterobranchia: Chromodorididae), Zoological Journal of the Linnean Society 20 (1), pp. 1-74 : 39-40

HYPSELODORIS PARADISA GOSLINER & JOHNSON SP. NOV.

(FIGS 2K, 13G, 18F, 22)

LSID: urn:lsid:zoobank.org:act:48A65392-E850-4EC0-BB40-E67E2322D01F

Type material

Holotype: CASIZ 191464 , subsampled for molecular study, dissected, reef close, 39 m depth, Pig (Tab Island), 5.1634°S, 145.83833°E, Madang Lagoon, Madang, Papua New Guinea, 28 November, 2012.

Type locality

Outer barrier reef north of Tab Island, Madang Lagoon, Papua New Guinea.

Geographical distribution

Presently known only from northern Papua New Guinea.

Etymology

Hypselodoris paradisa is named for the Greek word for paradise, referring to the tropical habitat of this species.

Description

External morphology: Living animal ( Fig. 18F ) moderately small, reaching 10 mm in length. Body translucent pink, with series of rows of opaque white spots, dashes and interrupted lines on dorsal surface of notum. V-Shaped reddish mark present posterior to rhinophores. Anterior and posterior ends of notum with purple markings; also present on posterior end of foot. Pink marginal band present along notal rim. Black spots arranged in linear rows between white markings. Six unipinnate gill branches having a translucent white base and bright red–orange pigment on apical surfaces and outer margin. Bulb of perfoliate rhinophores opaque white, with three red–orange transverse bands; bearing about ten densely arranged lamellae. Base of rhinophores translucent white.

Mantle glands: Subcutaneous mantle glands simple and rounded in shape ( Fig. 2K ). Glands densely situated anteriorly and posteriorly, with few glands present in the central lateral regions of body margin. About 15 glands on either side of anterior end of the body, with arc of ~20 glands situated posteriorly. Three lateral glands present on either side of lateral margin of notum.

Buccal armature: Muscular portion of buccal mass slightly longer than glandular portion of oral tube. Chitinous labial cuticle found at anterior end of muscular portion of the buccal mass bearing numerous jaw rodlets ( Fig. 22A ). Rodlets narrowly ovoid, with single, acutely pointed apex and wider base. Radular formula of holotype 46 × 55.0.55. Rachidian row of teeth absent ( Fig. 22B ). Innermost lateral teeth having single triangular denticles on inner side of bifid primary cusp, with another one to two outer denticles. Next several laterals lacking inner triangular denticle but possessing two or three denticles on outer side of primary bifid cusps. Midlateral teeth ( Fig. 22C ) all lacking inner denticles but having four or five sharply pointed, triangular outer denticles. Outermost teeth having a narrower base and shorter tooth shape, with four to six rounded outer denticles ( Fig. 22D ), often larger than bifid cusps.

Reproductive system: Reproductive organs of the holotype fully mature ( Fig. 13G ). Ampulla thin, tubular, narrowing somewhat before bifurcating into oviduct and vas deferens. Short oviduct entering female gland mass near albumen gland. Prostatic proximal portion of vas deferens convoluted, curved and thick, and narrowing slightly as it transitions into muscular ejaculatory portion. Ejaculatory portion highly convoluted and long, widening again before entry into broad penial bulb. Penial bulb adjacent to straight, very wide vaginal duct at common gonopore. Distal end of vas deferens devoid of penial hooks. Female gland mass consisting of large mucous gland and small membrane and albumen glands. Large, lobate vestibular gland situated near exit of mucous gland. Relatively short vagina leading to minute receptaculum seminis and larger spherical, thin-walled receptaculum seminis. Receptaculum adjacent to bursa at distal end of vagina. Moderately long uterine duct emerging from vagina close to base of bursa and female gland mass, near albumen gland.

Remarks

The phylogenetic relationship of this species to H. katherinae and H. skyleri is discussed above in the remarks section of H. katherinae . This species has similarity in its colour pattern to the sympatric species, H. maculosa and H. decorata , with the presence of opaque white lines and longitudinally arranged black spots. Despite the similarity of colour pattern, H. paradisa is in a distinct clade from both H. maculosa and H. decorata . Both H. paradisa and H. decorata have three reddish rhinophoral bands, whereas H. maculosa only has two bands. Hypselodoris paradisa has a reddish V-shaped patch on the head that is absent in both other species. Hypselodoris paradisa , like other members of its clade, has a broader radula than members of the H. maculosa clade and has a broad penial papilla, as in other members of its clade.

Figures

Figure 2. Mantle glands. A, Hypselodoris alburtuqali Gosliner & Johnson sp. nov., CASIZ 192295, holotype. B, Hypselodoris cerisae Gosliner & Johnson sp. nov., holotype, CASIZ 178350. C, Hypselodoris confetti Gosliner & Johnson sp. nov., CASIZ 191070. D, Hypselodoris decorata (Risbec, 1928), CASIZ 184316. E, Hypselodoris ghardaqana (Gohar & Abu-Ela, 1957), CASIZ 192282. F, Hypselodoris iba Gosliner & Johnson sp. nov., holotype, NMP 041279.

Figure 13. Reproductive systems. A, Hypselodoris ghardaqana (Gohar & Aboul-Ela, 1957), CASIZ 192282, scale bar: 3.5 mm. B, Hypselodoris iba Gosliner & Johnson sp. nov., CASIZ 177777, scale bar: 3.0 mm. C, Hypselodoris katherinae Gosliner & Johnson sp. nov., CASIZ 181257, scale bar: 1.0 mm. D, Hypselodoris lacuna Gosliner & Johnson sp. nov.,

Figure 18. Living animals. A, Hypselodoris lacuna Gosliner & Johnson sp. nov., paratype, CASIZ 177617, Tingloy, Batangas, Philippines. B, H. lacuna Gosliner & Johnson sp. nov., paratype, CASIZ 208188, Puerto Galera, Mindoro Oriental, Philippines. C, H. lacuna Gosliner & Johnson sp. nov., paratype, CASIZ 217345, Tingloy, Batangas, Philippines. D, H. lacuna Gosliner & Johnson sp. nov., paratype, CASIZ 208652, Puerto Galera, Mindoro Oriental, Philippines. E, Hypselodoris melanesica Gosliner & Johnson sp. nov., paratype, CASIZ 190823, Madang, Papua New Guinea. F, Hypselodoris paradisa Gosliner & Johnson sp. nov., holotype, CASIZ 191464, Madang, Papua New Guinea, photograph by Vanessa Knutson. G, Hypselodoris perii Gosliner & Johnson sp. nov., NMP 041281, Mabini, Batangas, Philippines. H, Hypselodoris roo Gosliner & Johnson sp. nov., paratype, CASIZ 204801, Puerto Galera, Mindoro Oriental, Philippines. I, H. roo Gosliner & Johnson sp. nov., CASIZ 208193, paratype, Puerto Galera, Mindoro Oriental, Philippines. J, H. roo Gosliner & Johnson sp. nov., paratype, CASIZ 186098, Mabini, Tingloy, Philippines.

Figure 22. Hypselodoris paradisa Gosliner & Johnson sp. nov., holotype, CASIZ191464. A, jaw rodlets. B, inner lateral teeth. C, middle lateral teeth. D, outer lateral teeth.