Geitodoris pusae

Alvim, Juliana & Pimenta, Alexandre Dias, 2013, Taxonomic review of the family Discodorididae (Mollusca: Gastropoda: Nudibranchia) from Brazil, with descriptions of two new species, Zootaxa 3745 (2), pp. 152-198 : 162-165

Geitodoris pusae (Er. Marcus, 1955)

( Figures 1 C; 7–8)

Discodoris pusae Er. Marcus, 1955: 147, figs. 151–165; Er. Marcus & Ev. Marcus (1970: 64, fig. 115); Ev. Marcus (1971: 944, fig. 44; 1972: 79; 1977: 10); Ev. Marcus & Er. Marcus (1967a: 82, figs. 105–107; 1969: 21, fig. 30); Thompson (1980: 88, figs. 7, 10).

Geitodoris pusae: Valdés et al. (2006: 178) ; García et al. (2008:144); Padula et al. (2012: 3); Edmunds (2011: 13, fig. 6D). Geitodoris planata auct non Alder & Hancock, 1846: García et al. (2008:209); Rios (2009: 427).

Type material. Probably lost. Not located in MZSP.

Type locality. Ilha de São Sebastião, São Paulo state, Brazil.

Material examined. U.S. A: Florida: Alligator Harbor: MZSP 75326, 18 /iii/1971, Franklin coll. [1]; Brazil: Alagoas state: Recife do Porto: MNRJ 13202, 07 /i/208, V. Padula coll. [1]; Rio de Janeiro state: Cabo Frio: Praia das Conchas: MNRJ 13198, 30 /viii/2008, J. Bahia coll. [1]; MNRJ 13200, 18 /v/2008, J. Bahia & V. Padula colls. [2]; Canal de Itajurú: MNRJ 14973, 23 /viii/2009, J. Alvim coll. [5; two dissected]; MNRJ 14972, 22 /viii/2009, J. Alvim coll. [3]; MNRJ 15032, 12 /11/2009, J. Alvim coll. [2]; Búzios: Praia da Tartaruga: MNRJ10952, 25 /v/2009, J. Alvim coll. [1]; Praia de João Fernandes: MNRJ 13201, 29 /01/2006, V. Padula coll. [2]; Arraial do Cabo: Praia do Forno: MNRJ 12794, 29 /iv/2006, J. Alvim coll. [2]; MNRJ 10787, 17 /vi/2006, J. Alvim coll. [1]; MNRJ 11023, 12 /ii/2007, J. Alvim coll. [1]; MNRJ 12793, 23 /iv/2007, J. Alvim coll. [1; one dissected]; MNRJ 11712, 23 /vi/ 2007, J. Alvim & P. Romano colls. [9]; MNRJ 11713, 23 /vii/2007, V. Padula coll. [1]; MNRJ 11757, 15 /vii/2007, J. Alvim coll. [1]; MNRJ 11832, 25 /viii/2007, J. Alvim coll. [1]; MNRJ 12056, 20 /x/2007, J. Alvim coll. [3]; MNRJ 12236, 25 /xi/2007, J. Alvim coll. [1]; MNRJ 13098, 20 /viii/2008, V. Padula coll. [1; one dissected]; Angra dos Reis: Ilha do Bonfim: MNRJ 17775, 27 /i/2010, J. Alvim coll. [1]; Praia de Mambucaba: MNRJ 15037,15/ x/2009, J. Alvim coll. [1]; São Paulo state: Ilha de São Sebastião: MZSP 13284, x/1915, E. Silva coll. [3].

Geographical distribution. U.S.A.: Florida, Puerto Rico, Curaçao (Ev. Marcus, 1977); Costa Rica; Martinique (Valdés et al., 2006); Jamaica (Thompson, 1980); Brazil: Pará state (Ev. MARCUS, 1970); Alagoas state (Padula et al., 2012); Rio de Janeiro state: Cabo Frio, Arraial do Cabo (present study), Búzios (Domínguez, 2006), Angra dos Reis (present study); São Paulo state: Ilha de São Sebastião (Er. Marcus, 1955), Ilhabela e Ilha das Cabras (Domínguez, 2006); Argentina (Ev. Marcus, 1977).

Description. External morphology ( Figures 1 C; 7E–F): body elliptical, slightly depressed, up to 25.0 mm long alive, with 1.5 to 1.7 times greater length than width. Mantle coriaceous, densely covered by somewhat rounded tubercles irregularly disposed; tubercles of different sizes (diameter: 113 µm to 435 µm); tubercles lower in mantle edge and in center of mantle than those in sides of mantle. Rhinophoral sheaths prominent, densely covered by tubercles, and sometimes with some granules. Rhinophores with cylindrical apex, 12 to 15 diagonal perfoliations. Branchial sheath prominent and smooth, without tubercles. Gill with six-eight retractile, tripinnate branchial leaves, symmetrically positioned along longitudinal axis of body; anal cone high, located between two most posterior branchial leaves. Foot narrower than mantle; anteriorly bilabiated and notched on two “lips”; posteriorly, can project in a rounded tail. Oral tentacles conical and short. Color of living specimens ranges from beige to brown, sometimes vivid orange, with several dark brown blotches on dorsum of irregular sizes and arrangement, and sometime with beige granules star-like; ventrally, orange; rhinophores with same tone as mantle, with some whitish spots on perfoliations and, apical part white; anteriorly branchial leaves and branchial sheath beige and, posteriorly branchial leaves translucent orange.

Labial cuticle and radula ( Figures 7 A–D): Labial cuticle with numerous elongated elements, irregularly disposed. Radula formula 19 x 27.0. 27 in specimen measuring 22.0 mm in length and 22 x 33.0. 33 in specimen measuring 21.0 mm in length; innermost lateral teeth hook-shaped, smooth or with one denticle, this can be insipient or not, in its inner surface; lateral teeth hook-shaped, smooth, larger and more developed in center of rows; marginal teeth spatulate, elongated and thin, with serration beginning on a concave part of teeth following distal part until convex part.

Reproductive system ( Figure 8 A): hermaphrodite duct connected to long and slightly convoluted ampulla. Postampullary gonoduct very short, that connects to oviduct and prostate. Prostate granular, divided into two parts, approximately of same size, less dense part proximal, denser distal part. Vas deferent elongated and convolute, slightly enlarged near genital atrium. Vagina elongated, thinner than deferent duct, opening into rounded bursa copulatrix. Bursa serially arranged, vaginal duct folding once and connecting to short-stalked seminal receptacle; bursa copulatrix with three times more volume than seminal receptacle; uterine duct short. In genital atrium, near vagina opening, there is a rounded vestibular gland.

Biology ( Figures 8 B–C): egg mass white as a spiral ribbon of 5.0 mm to 19.0 mm diameter and 2.0 mm of height, with crenulated border; ribbon with around 2.5– 3.5 whorls in counterclockwise direction and with numerous rows of many tiny eggs (egg capsule approximately 50 µm) irregularly disposed.

Remarks. Geitodoris pusae fits perfectly in the genus Geitodoris Bergh, 1891 , because this species presents all the diagnostic features of the genus, including the dorsum covered with simple tubercles ( Figs. 7 E–F); head with two conical oral tentacles; anterior border of the foot grooved and notched; labial armature armed with jaw elements ( Fig. 7 A); radula composed of hamate teeth, occasionally denticulate ( Fig. 7 B); outermost lateral teeth multidenticulate ( Figs. 7 C–D); reproductive system with a flattened, granular prostate, having two well differentiated regions ( Fig. 8 A); penis and vagina devoid of hooks; and there is a peduculate accessory gland ( Fig. 8 A) (Valdés, 2002).

The specimens studied here present the same general characteristics pointed out by Er. Marcus (1955) as the general coloration, that is light orange with brown blotches, irregularly distributed on the notum, and there are light granules. The color of the gill in all specimens always followed the same pattern: the anterior branchial leaves are beige and the posterior leaves are translucent orange. Despite being evident in most specimens, this feature has not been previously mentioned. However, an illustration of a specimen from Florida by Er. Marcus and Ev. Marcus (1967a, p. 83, Fig. 105) indicates the presence of dark posterior branchial leaves.

Er. Marcus (1955) reported the marginal teeth as worn, whereas Marcus and Marcus (1967a) described its margins as containing minute irregular denticles. In fact, we observed that in some cases the marginal teeth are worn, but in well-preserved specimens, a serrated pattern is present ( Fig. 7 D).

Geitodoris pusae was recorded from the Canary Islands and Mediterranean Sea (Ortea et al. 1988; Ortea, 1990; Tocino et al. 2006). We observed important morphological differences between these earlier descriptions and the specimens collected from Brazil. The specimens described by Ortea et al. (1988); Ortea (1990) and Tocino et al. (2006) present serrations in the marginal teeth of the radula (when this serrations are present) restricted to the distal part of the tooth, whereas in the specimens from Brazil the serrated portion occurs in all concave surfaces of the teeth. Furthermore, in specimens from Europe, a denticle in the innermost lateral tooth, even incipient, has never been reported. In European specimens, the gill is always brown with lighter tips and the branchial sheath is the same tone as the rest of the mantle; however, in Brazilian specimens the branchial leaves located anteriorly are beige, the more posterior branchial leaves are translucent orange, and the smooth branchial sheath is also beige. Ortea et al. (1988) and Ortea (1990) illustrated the reproductive system as presenting a narrow and long vestibular gland with an elongated shape and a long duct, whereas in specimens from Brazil, the vestibular gland is rounded with a short duct ( Fig. 8 A), more similar to the description of Tocino et al. (2006) for Mediterranean specimens. The differences that were observed in all specimens from Europe, in terms of coloration, gill morphology, and radula, lead us to consider the species from Europe as distinct from Western Atlantic G. pusae .

Geitodoris includes four valid species in the Western Atlantic: Geitodoris pusae , Geitodoris planata (Alder & Hancock, 1846) , Geitodoris patagonica Odhner, 1926 and Geitodoris immunda Bergh, 1894 . García et al. (2008, p. 209) recorded Geitodoris planata , a species originally described for European waters and with amphiatlantic distribution (Valdés et al., 2006), from the Brazilian Coast. However, the present study is dealing with the same morphotype treated by García et al. (2008) and this is clearly G. pusae and does not constitute G. planata . According to the re-description made by Cervera et al. (1985) the morphotypes studied here do not represent G. planata because G. planata presents the marginal teeth spatulate and with a smooth edge, while in G. pusae there is a serration beginning on a concave part of teeth following distal part until the convex part; G. planata has the lateral teeth hooked, without any kind of denticulation, while in G. pusae the innermost lateral teeth is hook-shaped and can be smooth or with one denticles; G. planata has a bilobed vestibular, although G. pusae has only one rounded vestibular gland.

Geitodoris immunda Bergh, 1894 , a species from Costa Rica and Venezuela, is the most similar to Geitoris pusae . G. immunda has only been referenced twice: an original description (Bergh, 1894) that is very general and does not enable these two species to be distinguished and a subsequent description by Valdés et al. (2006) that is very brief. Valdés et al. (2006) mentioned that this species has a branchial sheath with a characteristic wavy edge, but they do not provide an explanation for this feature. In the original description by Bergh (1894), the branchial sheath was not described. If the branchial sheath is smooth, this characteristic would match our description of G. pusae . We identified two differences between G. pu s a e analyzed herein and the species description by Bergh (1894): the number of diagonal perfoliations of the rhinophores, which have a range of 12–20 in G. pusae , whereas G. immunda presents 30 perfoliations; and the color of branchial leaves i.e., all specimens observed alive in this paper presented beige anterior branchial leaves and translucent orange more posterior leaves, whereas the gill of G. immunda is brown with white tips (Bergh, 1894; Valdés et al., 2006). Clearly, a comparative study between these two species, as well as a complete description of G. immunda , is needed.

Figures

FIGURE 1. Living specimens; A, Thordisa diuda (MNRJ 13195, 9 mm), photo: V. Padula; B, Hoplodoris hansrosaorum (MNRJ 12924, 22 mm); C, Geitodoris pusae (MNRJ 11712, 12 mm); D, Discodoris branneri (MNRJ 14922, 87 mm); E, Discodoris hummelincki (MNRJ 13997, 32 mm); F, Diaulula greeleyi (MNRJ 14974, 10 mm); G, Rostanga byga (MNRJ 12371, 5 mm); H, Jorunna spazzola (MNRJ 13196, 5 mm), photo: V. Padula.

FIGURE 7. Geitodoris pusae, SEM photographs; A, labial cuticle; B, inner surface of the innermost lateral tooth; C, outermost lateral teeth; D, detail of the marginal teeth, serrated portion of the teeth indicated by white arrow; E – F, tubercle; F, organic portion of the mantle removed. A – B (MNRJ 12793); C – F (MNRJ 14973).

FIGURE 8. Geitodoris pusae (MNRJ 14973); A, general view of reproductive system; B, egg mass; C, SEM photograph showing egg capsules. Abbreviations: am, ampulla; bc, bursa copulatrix; dd, deferent duct; f, female glands; go, gonopore; ov, oviduct; pr, prostate; s, seminal receptacle; u, uterine duct; va, vagina; vg, vestibular gland.