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Records of the Australian Museum (2017) Vol. 69 
Figure 12. World late Miocene-early Pleistocene fossil localities for Janthina species, and purported fossil record of Recluzia. Symbols: 
A, Janthina chavani) ▼, Janthina globosa: m, Janthina krejcii) • , Janthina typica) O, incorrect fossil record of Recluzia. Localities: (1) 
Fouarat, near Casablanca, Morocco ( J. typica ; type locality of Acrybia chouberti Chavan); (2) La Esfinge, Gran Canaria, Canary Islands 
(J. typica)\ (3) Selvagem Grande I. (J typica or possibly J. chavani)-, (4) Sao Vicente, Madeira (J. typica or possibly J. chavani)-, (5) 
Santa Maria I., Azores (type locality of both J. typica and J. krejcii sp. nov.); (6) Kane Megamullion, mid-Atlantic Ridge (J. chavani, type 
locality of Kaneconcha knorri Kaim, Tucholke & Waren); (7) Bowden, Jamaica (J. globosa)-, (8) Casa Cantaure, Paraguana Peninsula, 
Venezuela (incorrect early Miocene record of Recluzia)-, (9) dredge station off Itaunas, Espiritu Santo, Brazil (J. typica, type locality of 
Eunaticina abyssalis Simone); (10) SE Japan (J. typica and J. chavani)-, (11) Anda, Cabarruyan I., Luzon, Philippines (J. globosa)-, (12) 
southern Australia (J. typica and J. chavani)-, (13) northern and southwestern New Zealand (J. typica and J. chavani). More detailed 
localities in the Atlantic islands, New Zealand, southern Australia and Japan are shown on succeeding maps. 
has not evolved as many adaptations to neustonic life as 
Janthina has. With the passage of time, predation pressure 
could have enhanced the protective violet coloration of the 
shell of Janthina, again implying that, lacking protective 
coloration, Recluzia likely is the more recent adopter of the 
neustonic habit. 
The neustonic habit and the necessary modification of the 
pedal mucus gland to allow it to form a bubble float rather 
than chalazae, along with other adaptations to neustonic life 
such as the lack of an operculum and the laying of modified 
egg capsules on the underside of the float, provide the only 
distinctive characters of Janthina and Recluzia. These 
characters seem to be of ecological significance rather than 
phylogenetically informative, as was also concluded by 
Lalli & Gilmer (1989: 22-23). There seems to be no reason 
to regard Janthina and Recluzia species as anything other 
than neustonic Epitoniidae and, as noted above, this has been 
demonstrated from molecular sequences by Churchill et al. 
(2011a) and Takano & Kano (2014). It is concluded that 
Janthina and Recluzia are epitoniids that independently have 
adopted neustonic life, feeding on distinct prey, Janthina on 
mixed prey but mainly on Physalia, Velella and Porpita, and 
Recluzia species mainly (entirely?) on minyadid anemones. 
This is separate from the question of whether Nystiellinae 
Clench & Turner (1952: 336) should be recognized at 
family-group level (Nystiellidae: Niitzel, 1998: 90, 128), a 
question to be resolved by molecular comparisons. Janthina 
and Recluzia share the weakly sculptured protoconch of 
planktotrophic taxa assigned to Epitoniinae rather than the 
prominently axially ribbed protoconch of planktotrophic 
taxa assigned to Nystiellinae. 
The fossil record 
To establish accurate time ranges in order to date the 
evolutionary history of neustonic Epitoniidae, it is important 
to establish the localities and their ages where fossils of 
Janthina have been recorded. The writer is not aware of 
fossils of Recluzia, the one putative but incorrect record 
is shown in Figure 12, which shows the areas of the world 
where Janthina fossils have been recorded. Localities in the 
Atlantic islands, New Zealand, southern Australia and Japan 
are shown in more detail on succeeding maps. 
The succession on Santa Maria Island. The small Santa 
Maria Island (17 km E-W, 6 km N-S; Fig. 13) is the oldest 
and south-easternmost of a complex chain of volcanic 
islands forming the Azores, in the eastern North Atlantic. 
It is important for the present report because the island 
is the type locality of the stratigraphically earliest and 
earliest-described fossil Janthina species, J. typica (Bronn, 
1861). The stratigraphy of Santa Maria Island was mapped 
and described by several earlier authors, notably Hartung 
(1861), Zbyszewski et al. (1961), Zbyszewski & da Veiga 
Ferreira (1962a) and Serralheiro & Madeira (1993). Helpful 
descriptions were also provided by Krejci-Graf etal. (1958) 
and Krejci-Graf (1961). Santa Maria is unique among Azores 
islands in having Pliocene (Zanclean) and, it was thought 
until recently, small areas of latest Miocene (Messinian 
and even possibly Tortonian) limestone and fossiliferous 
tuffaceous lenses interbedded between the lava flows. All 
other Azores islands are younger, and have no marine fossils. 
The localities on Santa Maria Island where limestone and 
other sedimentary lenses crop out were mapped in detail 
