GOSLINER & BERTSCH: NEW SPECIES OF NUDIBRANCH MOLLUSKS, MEXICO 123 
Figure 4. Reproductive anatomy. A. Rostanga ghiselini sp. nov., holotype, CASIZ 220373. B. Tenellia ivetteae sp. 
nov., paratype, CASIZ 222482. abbreviations: al-albumen gland, am ampulla, bc-bursa copulatrix, ej-ejaculatory portion of 
vas deferens, fg-female gland mass, me-membrane gland, mu-mucous gland, p-penis, pg-penial gland, pr-prostatic portion 
of vas deferens, rs-receptaculum seminis, st-penial stylet, v-vagina, vd-vas deferens, vg-vestibular gland. Scale = 1 mm. 
na, long narrow uterine duct leading to smaller receptaculum seminis. Receptaculum seminis pyri¬ 
form with short duct entering the female gland mass. 
Remarks. — Rostanga ghiselini differs from all other 23 described members of the genus. 
Most species of Rostanga, as in R. ghiselini, have a reddish or orange body color, except for R. seti- 
dens (Odhner, 1939) (whitish), R. phepha Garovoy, Valdes and Gosliner, 2001 (white), R. risbeci 
Baba, 1991 (dark gray to black), R. ankyra Valdes, 2001 (white) and R. crocea Edmunds 2011 (yel¬ 
low). Species of Rostanga have rhinophores of two basic forms, either conical with a series of 
transverse lamellae, as in most other dorid nudibranchs, including R. ghiselini, or broader 
rhinophores with nearly vertical lamellae (Table 1). Twelve species have transverse lamellae while 
11 have vertical ones. 
The buccal armature, both the jaws and radula, of most Rostanga species is distinctive. In six 
species, R. ankyra, R. aureommala Garovoy, Valdes and Gosliner, 2001, R. crocea, R. elandsi 
Garovoy, Valdes and Gosliner, 2001, R. rosi (Ortea, 1979) and R. setidens lack any trace of jaw 
rodlets, while the remaining species, including R. ghiselini, either have small areas of the labial 
cuticle with jaw rodlets or well developed rodlets. The inner lateral tooth of many species of 
Rostanga often contains a series of distinct denticles. This arrangement is found in 16 species of 
Rostanga, while five species have a bifid or simply hamate inner tooth. In R. crawfordi (as R. aus¬ 
tralis), Rudman and Avem (1989) noted that small specimens have a denticulate inner lateral 
whereas medium-sized or large specimens have an entirely smooth inner lateral. Of the species 
with a denticulate inner lateral tooth, only R. ghiselini and R. rubra have a secondary triangular 
cusp below the inner margin bearing numerous denticles. In R. ghiselini this cusp is far more pro¬ 
nounced than in R. rubra (Valdes and Gosliner, 2001; Edmunds, 2011). Also, in R. rubra, some of 
the middle lateral teeth near the point where the hamate teeth become more elongate, lack a sec¬ 
ondary denticle, whereas all of them in R. ghiselini have a secondary denticle. 
Rostanga ghiselini can be compared in detail with the only other species found in the eastern 
Pacific, R. pulchra MacFarland 1905. Both species are reddish orange in color, but R. ghiselini also 
has large black spots present on the notum. The rhinophores of R. ghiselini are conical with trans- 
