Chromodoris quagga Bonomo & Gosliner 2020, sp. nov.
Creators: name: Bonomo, Lynn J.
name: Gosliner, Terrence M.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Nudibranchia
Chromodorididae
Chromodoris
Chromodoris quagga

description: Chromodoris quagga Bonomo & Gosliner sp. nov.
Figures (2G, 2H, 11, 12)
urn:lsid:zoobank.org:act: 4833E0CD-5B91-419E-8267-59C4CBE74E7C
Chromodoris sp. 11— Gosliner et al. 2018: 139, middle right photograph.
Chromodoris burni — Gosliner et al. 2015: 212, bottom right picture, misidentification.
Type material. Holotype: NMP 041294 formerly from CASIZ 177428, one specimen, subsampled. Bethlehem dive site, 13.67280°N 120.84130°E, Maricaban Island, Tingloy, Batangas Province, Luzon Island, Philippines, 21 m depth, 19 March 2008, T. M. Gosliner et al. Paratypes: CASIZ 177426, one specimen, subsampled and dissected. Bethlehem dive site, 13.67280°N 120.84130°E, Maricaban Island, Tingloy, Batangas Province, Luzon Island, Philippines, 19 March 2008, T.M. Gosliner et al. CASIZ 184320, one specimen. Bethlehem, Maricaban Island, Batangas Province, Philippines, 2 October 2010, Peri Paleracio. CASIZ 229987, one specimen, dissected. Red Rocks dive site, Batangas Bay, Batangas Province, Luzon Island, Philippines, 12 November 2017, Peri Paleracio.
Type locality. Bethlehem dive site, Maricaban Island, Tingloy, Batangas Province, Luzon Island, Philippines.
External morphology. Living animals (Figs. 2 G–H) are moderately large, with a length around 35 mm. Body is light brown in color with long black stripes across the mantle. The marginal band is a bright yellow that surrounds the entire mantle and there are black spots between the marginal band and the stripes on the mantle. Twenty unipinnate gill branches are translucent white in color with bright orange on the rachis of the gill branches. The perfoliate rhinophores are orange with an opaque white band around the bottom and have 16 distinct lamellae. The posterior end of the foot extends past the posterior end of the mantle and has a thinner yellow marginal band and a few brown stripes. On either side of the mouth there is a pair of digitiform oral tentacles.
Internal morphology. Mantle glands (Fig. 11A): The mantle glands are subcutaneous around the edges of the mantle margin. However, in preserved specimens it is difficult to observe the exact shape of the mantle glands and pictures of the live nudibranchs also do not show the shape of mantle glands. The mantle glands of C. quagga are U-shaped with extensions heading out both sides of the U.
Buccal mass and radula: The muscular portion of the buccal mass is slightly smaller than the oral tube length. Two long, straight salivary glands extend from the anterior end of the esophagus and the posterior end of the muscular portion. These salivary glands are on either side of the esophagus and connect at the point where the esophagus joins the buccal mass. A chitinous labial cuticle is found at the anterior end of the muscular portion (Fig. 11B) with long, bifurcated jaw elements (Fig. 12 A–B). The radular formula for the two paratypes, CASIZ 177426 and CASIZ 229987, is 73 x 68.1.68 and 64 x 55.1.55, respectively (Fig. 12C). The rachidian tooth is thin and triangularly shaped without a distinct cusp but appears to twist as it extends. On either side of it, the inner lateral teeth have 3 denticles on the inner side and 3–4 denticles on the outer side (Fig. 12D). The inner lateral tooth has an elongate center cusp that is about twice the length of the adjacent denticles. The remaining laterals only have denticles on the outer side of the central cusp. The middle lateral teeth have an elongate cutting edge with 5 to 7 acutely pointed denticles with the central cusp being three times the length of the denticles (Fig. 12E). The outer lateral teeth are elongate with 4 to 6 rounded denticles (Fig. 12F).
Reproductive system (Fig. 11C): The thin pre-ampullary duct connects the ovotestis with the elongate and convoluted ampulla. The ampulla narrows proximally and divides into a short oviduct and an elongate vas deferens. The distal portion of the vas deferens is wide, convoluted, and prostatic. The prostatic portion narrows proximally and enters the short curved ejaculatory segment. This segment expands into the wider penial bulb, which also joins with the distal end of the vagina. The vagina is moderately long and curved and enters the base of the thin-walled, massive, spherical bursa copulatrix. Also, joining at the base of the bursa is the receptaculum seminis duct, which connects with the large pyriform curved receptaculum seminis. Along the length of the receptaculum seminis duct is a short branch of the uterine duct that enters the female gland mass. The female gland mass is composed of a small albumen and membrane glands and a larger mucous gland. There is a large, bulbous vestibular gland joining the base near the genital opening.
Etymology. The name Chromodoris quagga comes from the scientific name of the Plains zebra (Equus quagga). The striped nature of this nudibranch reminded us of the well-known striped pattern that zebras use for disruptive coloration.
Geographical Distribution. This species has been found in the Philippines.
Remarks. Our phylogenetic, ABGD, and bPTP analyses indicate that C. quagga represents a distinct species. The shortest COI uncorrected pairwise distance between C. quagga and C. orientalis, the sister taxa, is of 7.00%. For C. burni, C. striatella, and C. lineolata, the more similar looking Chromodoris, minimum uncorrected pairwise distances are of 8.52%, 7.51%, and 6.51% respectively. Chromodoris quagga is most similar to C. burni, with brown pigment on the body, a series of white longitudinal lines, and an orange gill and rhinophores that lack white spots. Chromodoris striatella, C. lineolata, and C. balat all have opaque white spots on the rhinophores and gill. The body size of C. quagga (35 mm) is much larger than C. burni (9–11 mm). The radula of C. quagga has a long thin rachidian tooth whereas C. burni (Rudman 1982: fig. 11) has a shorter tooth with a medial thickening. The lateral teeth of C. quagga have a longer more acutely pointed cusp than do those of C. burni. The outer lateral teeth are much longer than those found in C. burni. The reproductive system of C. burni was not described or illustrated and cannot be compared with that of C. quagga.
description: Published as part of Bonomo, Lynn J. & Gosliner, Terrence M., 2020, Adding stars to the Chromodoris (Nudibranchia, Chromodorididae) galaxy with the description of four new species, pp. 401-435 in Zootaxa 4819 (3) on pages 426-427, DOI: 10.11646/zootaxa.4819.3.1, http://zenodo.org/record/4397003