Beu: Evolution of Janthina and Reduzia 
135 
modified for unknown reasons in some specimens. The two 
published observations of young specimens of Reduzia lutea , 
by Colman (1986) and Churchill et al. (2011 b), both reported 
small specimens, assumed to be males, located on the foot 
or float of a large adult female, implying that a single cycle 
of protandry also occurs in Reduzia species. The specimen 
of Churchill et al. (2011b: figs 1A-B) is in a photograph by 
Denis Riek taken in northern New South Wales, repeated here 
(Fig. 6C). The same physical relationship is confirmed by now 
dry specimens collected alive on a beach in northern New 
Zealand, in which several larval shells are preserved in dried 
mucus material attached to larger shells (see below under R. 
lutea ; Fig. 37). This implies, however, that the production of 
a mucous string and single-bubble “proto-float” by juvenile 
specimens of Janthina species (Simroth, 1895; Churchill et 
al ., 2011b) did not evolve in Recluzia. Churchill etal. (2011b) 
recognized that this is a further significant distinction between 
the genera Janthina and Reduzia. Further research clearly 
is desirable on the life cycle and reproductive strategies of 
neustonic Epitoniidae. 
Protoconchs. Simroth (1895: fig. 3) and Robertson (1971: 
pis 5-6) illustrated larval shells of several Janthina species 
attached to their teleoconchs at an angle to the teleoconch 
coiling axis. Albany (1940) also pointed out that the 
protoconch of Janthina is inclined to the coiling axis of the 
teleoconch. Richter & Thorson (1975: 136) also illustrated 
shells of veligers, demonstrating that they are very similar 
to the protoconchs of planktotrophic benthic Epitoniinae. 
Lalli & Gilmer (1989: fig. 6) illustrated the larval shell of 
an unidentified Janthina species with a unique rectangular 
projection on the outer lip resembling that of a classic 
neogastropod sinusigera larva, although the projection is not as 
long or strongly hooked as in a sinusigera. Fretter & Graham 
(1962: 402, fig. 211), Robertson (1976: 217-219, figs 4-5), 
Collin (2000: fig. 20), Gittenberger & Gittenberger (2005) 
and many other authors have described the numerous, small, 
sand-agglutinated egg capsules linked together by elastic 
threads (chalazae) of benthic Epitoniidae and contrasted 
them with the larger capsules attached to the underside of 
the float in Janthina and Reduzia. Robertson (1976) also 
commented that although J. janthina is ovoviviparous (i.e., 
it broods its eggs in the oviduct) while all four other Janthina 
species are oviparous, the late larval stages of all five species 
are planktotrophic veligers, as is the case for Reduzia lutea 
and presumably Rjohnii. Robertson (1983: 10) also pointed 
out the similarity between the protoconch microsculpture of 
Epitonium and Janthina “first shown by Richter and Thorson” 
(1975: 136). Protoconchs examined for this report show that 
the Janthina protoconch is slightly shorter than those of most 
benthic Epitoniidae, but this appearance is the result partly 
of a truly slightly shorter larval shell (Robertson, 1971: fig. 
22; 2007a: 8, text-fig.) and partly of the high angle of the 
coiling axis of the protoconch to that of the teleoconch in 
some species, so that the protoconch is enclosed slightly in 
the teleoconch. Protoconchs are particularly inclined at a high 
angle in specimens of J. janthina examined (Figs 32A-D) but 
are inclined at only a slight angle in J. exigua, J. globosa and J. 
umbilicata (Figs 30A-B, 34C, F, H), whereas the protoconch 
is parallel to the teleoconch coiling axis in Reduzia lutea 
(Figs 37B-F). Protoconchs of J. pallida and Rjohnii were 
not available for examination. Rolan & Trigo (1973: fig. 3) 
illustrated that of J. pallida well, demonstrating that it is almost 
parallel to the coiling axis of the teleoconch, but is unusually 
short, only c. 2 whorls protruding from the teleoconch apex. 
They commented that “it is not possible to see how many 
whorls are present, because the lowest part is covered by 
the teleoconch” (Rolan & Trigo, 1973: 56). The obvious but 
fine, narrow, axial grooves and weak spiral grooves, with 
weak, rectangular deviations of the axial grooves where 
they are crossed by the spiral grooves, shown in Robertson’s 
(1971, figs 18-19, 22) illustrations of Janthina larval shells, 
are also visible in all protoconchs of Janthina species and 
R. lutea examined here. The protoconch of J. typica , type 
species of Hartungia, has not been available despite a 
careful search of available well-preserved material, notably 
New Zealand material and that from the Roe Calcarenite in 
southern Australia. As noted below under the type material 
of Eunaticina abyssalis Simone, 2014 (= Janthina typica ), 
its supposed protoconch illustrated by Simone (2014: figs 
101—J) is the corroded apex of the Janthina teleoconch, rather 
than the protoconch. The protoconch of J. typica cannot be 
evaluated as yet. Recluzia lutea has a protoconch closely 
similar to that of Janthina species in shape and sculpture, but 
has one fewer whorls. All Janthina and Recluzia protoconchs 
examined have a protoconch I of just over one smooth whorl, 
with an obvious but narrow terminal groove. That of Janthina 
species examined (counted in J. exigua and J. janthina ) has 
a protoconch II of 3.2 whorls (Figs 32B, 34C, F), whereas 
protoconch II of R. lutea consists of only 2.2 whorls (Fig. 37B). 
Spermatozeugmata. Graham (1954) described the repro¬ 
ductive anatomy of Janthinajanthina , based on the specimens 
collected in Cornwall by Fowler (1946a, b). He provided 
details of the anatomy, and again reported fertilization by 
the spermatozeugmata described by Ankel (1930). All adults 
Graham examined were protandrous hermaphrodites and 
lacked a penis when in the male phase. This is equally true 
of all adult males observed since, so the large swimming 
spermatozeugmata provide the means of transferring sperm 
between individuals. Egg capsules and spermatozeugmata of 
Janthina were described also by Muller (1863), Baldasseroni 
(1916) and Ankel (1926,1930), among others. Collin (2000: 
table 1) when describing the anatomy and development 
of Nitidiscala tincta (Carpenter, 1865) pointed out that 
spermatozeugmata are produced by Epitoniidae, Janthinidae, 
Cerithiopsidae and Triphoridae, among the families included 
in Ptenoglossa by some authors. Spermatozeugmata were 
described also in benthic Epitoniidae by Bulnheim (1962, 
1968), Melone et al. (1978, 1980) and McDermott (1981). 
Nishiwaki & Tochimoto (1969) described two distinct sizes of 
spermatozeugmata, both present in two species of Epitonium. 
Healy (1994) and Robertson (2007b) also described the 
incidence of spermatozeugmata in families Epitoniidae, 
Janthinidae, Cerithiopsidae and Triphoridae, but Healy (1994) 
pointed out that those of Cerithiopsidae and Triphoridae are 
strongly distinct from those of Epitoniidae and Janthinidae. 
Once again, spermatozeugmata have not been reported in 
Recluzia species, but presumably they are present, as males 
of Recluzia species also lack a penis. This again reflects 
the need for further research on this rare genus. Identical 
spermatozeugmata provide another character common to 
benthic and neustonic Epitoniidae. 
Egg capsules and brooding. Recluzia species and most 
species of Janthina secrete egg capsules attached to the 
underside of their bubble float by hardened mucus that 
forms a short stalk at the narrow end of the capsule. The 
