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2 Other species of Globiscala de Boury (1909) (type 
species Scalaria bullata G. B. Sowerby II, 1844, 
Recent, Indo-West Pacific; Weil etal ., 1999: 54, fig. 
140). 
3 Sagamiscala Masahito, Kuroda & Habe in Kuroda 
etal. (1971: 258) (type species Sagamiscala glob osa 
Masahito, Kuroda & Habe, 1971, Recent, Japan; Weil 
etal. , 1999: 124, fig. 394). 
4 Librariscala Kilbum (1985: 302) (type species Scalaria 
millecostata Pease (1861), Recent, Indo-West Pacific). 
The sculpture of Alora is most similar to that of early 
Janthina species, with fine axial ridges and more prominent 
spiral cords. Keen (1971: 436) recorded the presence of a 
“dull buff 5 periostracum (an intritacalx?) in the type species 
of Alora, A. gouldii, and Weil etal. (1999: 144) described it 
as “The shell is white underneath a thin buffy periostracum”. 
The protoconch of illustrated Alora species (Bouchet & 
Waren, 1986: figs 1227-1228) is of lecithotrophic epitoniine 
type, relatively short and inflated, with very fine, closely 
spaced spiral and axial sculpture, and does not resemble 
that of Janthina species in detail. If Janthina evolved from 
Alora , it did so before Alora lost planktotrophy. DeVries 
(2007) described a middle Miocene species of Alora from 
Peru, confirming that Alora pre-dated the evolution of 
Janthina. However, Alora teresmonile DeVries, 2007 has a 
taller spire and much finer and closer spiral sculpture than 
my Janthina species. Some North Pacific species previously 
referred to Alora were revised by Nakayama & Hasegawa 
(2016); some were transferred to Epidendrium (Epitoniidae) 
and one to the genus Tuba (Mathildidae, Heterobranchia). 
Alora tenerrima (Dautzenberg & Fischer, 1896) (Bouchet & 
Waren, 1986: 542, fig. 1251) is perhaps the benthic epitoniine 
most closely resembling Janthina typica. It is relatively short 
and has few (c. 10), widely spaced spiral cords and uniform, 
fine axial ridgelets similar to those of Janthina species over 
the entire teleoconch surface. Viewing the bubble float of 
Janthina and Recluzia species as a modified epitoniid egg 
mass (Churchill et al ., 2011a) shows how the change from 
a benthic to a neustonic mode of life might have occurred 
rapidly through a relatively minor mutation. 
In contrast, the complete lack of any fossil record implies 
very recent adoption of the neustonic habit by Recluzia 
species, presumably by very similar modifications of the 
pedal mucus gland and egg mass. The bright yellow animal 
tissue suggests that Recluzia possibly evolved from a 
benthic epitoniid similar to Surrepifungium Gittenberger 
& Gittenberger, 2005 or Epidendrium Gittenberger & 
Gittenberger, 2005, which have similar bright yellow 
tissues. However, shell character similarity makes it seem 
more likely that Recluzia evolved from a smooth brown 
epitoniid similar to Alexania Strand, 1928. Comparison 
of molecular sequences should resolve these possibilities. 
Robertson (1997) illustrated a specimen of Alexania 
floridana (Pilsbry, 1945) found in Texas, and commented 
that Alexania is “conchologically ... the epitoniid equivalent 
of the janthinid genus Recluzia ...” (Robertson, 1997: 
11). The name Alexania has had a complex nomenclatural 
history. Its synonyms include Alexandria Tomlin, 1926, type 
species Alexandria natalensis Tomlin, 1926, Recent, South 
Africa; junior homonym of Alexandria Pfeffer (1881: 63; 
Echinoidea); Problitora Iredale (1931: 216), type species 
Amauropsis moerchi A. Adams & Angas, 1864, eastern 
Australia; Tomlinula Strand (1932), unnecessary new name 
for Alexandria^ Habea Kuroda, 1943, type species Habea 
inazawai Kuroda, 1943; and Stenacme Pilsbry, 1945, type 
species Stenacme floridana Pilsbry, 1945 (Robertson & 
Oyama, 1958; Robertson & Habe, 1965). Robertson (1997) 
suggested that there is only one widespread species of 
Alexania , A. natalensis (= Amauropsis moerchi , Habea 
inazawai and Stenacme floridana) although a spirally colour- 
banded second species, A. callizona (Habe, 1961) (Okutani, 
2000: pi. 170, fig. 118) is recognized in Japan. Hayase et 
al. (2015: 111, pi. 5, figs la-d) illustrated specimens of 
A. inazawai (i.e., A. natalensis) collected alive feeding on 
anemones under boulders at Maeshima Island, Mikawa 
Bay, Aichi Prefecture, Japan. Abbott (1974: 124) noted that 
Alexania preys on the benthic anemone Aiptasiomorpha 
luciae (Verrill, 1898) {Diadumene luciae ; Habe, 1943; 
Okutani, 2000: 343), introduced from Southeast Asia 
and occurring widely in eastern USA. Alexania reaches 
a smaller adult size (shell rarely more than 10 mm high) 
and has a slightly shorter and wider teleoconch shape 
than adult Recluzia lutea , and has a shallower suture and 
an adult operculum (Habe, 1943; Pilsbry, 1945). Its dark 
brown colour indicates that the shell likely is calcitic. 
Habe (1943) described and illustrated the creeping animal 
with operculum, radula, veliger larva, undivided cephalic 
tentacles, and egg capsules of Habea inazawai (i.e., A. 
natalensis). The numerous small egg capsules are bound 
together by elastic threads (Habe, 1943: 65). An unusual 
feature is the thin, smooth mantle lobes riding up over both 
sides of the shell as far as the spire apex (Habe, 1943: fig. 2; 
Okutani, 2000: pi. 170, bottom right fig.; Riek, 2017, living 
animal of “ Alexania moerchi ” illustrated), explaining the 
smooth teleoconch exterior. These mantle lobes resemble 
the epipodia of Janthina species closely, but presumably 
superficially. Robertson (1997: 11) noted that “ Alexania and 
Recluzia are brown transitional shell forms. The anatomy, 
like the ptenoglossate radula, is also similar ...”. Takano & 
Kano (2014: figs 1-2; Fig. 3B) also found Alexania inazawai 
to be the most nearly related to Janthina of the four species 
of benthic Epitoniidae they included in their molecular 
analysis. Both Alexania and Janthina were included in the 
same clade as Epitonium , and Opalia and Opaliopsis species 
belong in a second clade of Epitonioidea (Nystiellinae?; 
Opaliopsis Thiele, 1928 is now accepted as an earlier 
synonym of Nystiella Clench & Turner, 1952; Kilbum, 1985: 
259; Brown & Neville, 2015: 13; but Opalia H. Adams & 
A. Adams, 1853 has always been classified in Epitoniinae 
and species of Opalia certainly have the type of protoconch 
usually regarded as diagnostically epitoniine). More taxa 
evidently need to be included in molecular comparisons 
to resolve these relationships. It is feasible that Recluzia 
evolved recently from the benthic epitoniid Alexania , 
adapting to preying on floating anemones rather than benthic 
ones. Churchill et al. (2011a) interpreted the distinctions 
between Recluzia and Janthina (Table 1) as indicating that 
Recluzia evolved earlier and was ancestral to Janthina , and 
consequently Recluzia is not as fully adapted to neustonic 
life as Janthina is. However, the fossil record indicates that 
the opposite interpretation is much more likely; Recluzia and 
Janthina adopted a neustonic life independently, evolving 
from distinct ancestors. Janthina adopted neustonic life late 
in Miocene time. In contrast, Recluzia adopted neustonic 
life very recently, apparently late in Holocene time, and so 
