GONZALES & GOSLINER: NEW SPECIES OF PHILINE FROM THE INDO-PACIFIC 371 
widens and curves around the curved distal receptaculum seminis. The duct again narrows at the 
point where it enters the albumen and membrane glands. The albumen and membrane glands are 
small. The larger mucous gland is bilobed with a large primary lobe and small secondary one. After 
branching to the female glands, the hermaphroditic duct is elongate and narrow and extends to the 
genital aperture where it then joins the short duct of the small, curved distal receptaculum seminis 
and continues to the genital atrium, where it joins the elongate duct of the bursa copulatrix. The 
bursa is small and pyriform. Its duct is wide thi-oughout its length but is widest at the genital atri¬ 
um. There are no secondary bursae evident in the specimen dissected, but there is a swelling at the 
base of the bursa duct. From the genital atrium the open, ciliated spenn groove leads to the cephal¬ 
ic penis. The penis (Figs. 8E, 9F) is not fully mature and consists of a broad penial sac and a rela¬ 
tively short, compact, highly branched, posteriorly directed prostate gland and associated ducts that 
characterize members of the Philine aperta clade. Within the penial sac, a large hammer-shaped 
penial papilla with lobate flap on the anterior side of the lobed papilla (Fig. 9F).The papilla lacks 
any annature or other ornamentation, but was not entirely mature. 
Remarks. —This species is similar externally to other members of the Philine aperta clade 
(Price et al. 2011). Of the species known from deep water in the Indo-Pacific, P. habei Valdes, 
2008, P. rubra Bergh, 1905, and P puka Price, Gosliner, and Valdes, 2011, have a radula with no 
outer lateral teeth and have gizzard plates with a pair of relatively large pits on each gizzard plate. 
Philine puka has a narrower body shape than does either P habei or P. verdensis. The body shape 
of P. rubra is unknown. Also, P puka reaches a maximum length of 10 mm (Price et al. 2011) and 
is entirely sexually mature at that size, while a 17 mm specimen of P verdensis was not fully 
mature. The inner lateral teeth of P, habei were described as laeking dentieles, whereas the inner 
teeth of both P. puka and P, verdensis have a large number of denticles on the laterals. One speci¬ 
men identified here as P habei (CASIZ 177499) from the Philippines has a radula where most of 
the older radular teeth appear quite worn with only mdimentary denticles, whereas the newer teeth 
have strongly pronounced denticles. Rudimentaiy denticles also appear to be visible in Valdes’ fig¬ 
ure of P. habei (2008: fig. 64a). Much of the anatomy of P. rubra remains undescribed, but the 
penis is shown as having a distinct vesicle attached to the base of the penial sac that is not evident 
in the other species. Details of the penial papilla were not described for P. rubra, and it is likely 
that this species will remain unidentifiable owing to the incompleteness of the original description. 
Other morphological differences also appear to differentiate P verdensis, P habei, and P puka. 
In P. verdensis, the pores of the paired gizzard plates are oblong with one of the pores being 
markedly larger than the other. In P. puka and P. verdensis, the paired holes are very similar in size. 
The unpaired gizzard plate ofi^ puka and P verdensis is much smaller than the paired plates where¬ 
as in P habei all three plates are similar in size. The microstructure of the gizzard plates also dif¬ 
fers in the three species. In P. puka, there is a distinct honey-combed pattern present, whereas in 
P. habei (present study) there is some organization of a honeycomb pattern, but it is not as highly 
organized as in P puka. In P. verdensis, there is no indication of any organized micro structural pat¬ 
tern. The penial papilla of P. verdensis is hammer-shaped with a prominent flap on the anterior 
lobe, whereas in P. habei the penial papilla is asymmetrical with one lobe larger than the other or 
more of less equally lobed (present study). The penis of P. puka is smaller with markedly unequal 
lobes and a very short base. 
In the molecular phylogenetic analysis (Fig. 14), P. verdensis and P. habei are sister species, 
but have a p-distance of 4.2% in their 16S mitochondrial genes. This strongly supports them being 
considered as distinct species. Previously, Kmg et al. (2012) found that separate species of Philine 
have 16S p values greater than 1.0%, while separate populations of members of the same species 
had p values between 0.2-0.3%. 
