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Diet preferences of the Aglajidae: a family of
cephalaspidean gastropod predators on
tropical and temperate shores
andrea zamora-silva and manuel anto
’
nio e. malaquias
Phylogenetic Systematics and Evolution Research Group, Department of Natural History, University Museum of Bergen, University
of Bergen, PB 7800, 5020-Bergen, Norway
Aglajidae is a family of tropical and temperate marine Cephalaspidea gastropod slugs regarded as active predators. In order to
better understand their food habits and trophic interactions, we have studied the diet of all genera through the examination of
gut contents. Specimens were dissected for the digestive tract and gut contents were removed and identified by optical and
scanning electron microscopy. Our results confirmed that carnivory is the only feeding mode in aglajids and showed a
sharp preference for vagile prey (94% of food items). We suggest that the interaction between crawling speed, presence of sen-
sorial structures capable of detecting chemical signals from prey, and unique features of the digestive system (e.g. lack of
radula, eversion of the buccal bulb, thickening of gizzard walls) led aglajid slugs to occupy a unique trophic niche among
cephalaspideans, supporting the hypothesis that dietary specialization played a major role in the adaptive radiation of
Cephalaspidea gastropods.
Keywords: aglajids, Cephalaspidea, Mollusca, predation, trophic ecology
Submitted 9 February 2015; accepted 29 April 2015
INTRODUCTION
Aglajidae is a diverse group of predominantly shallow-water
cephalaspidean gastropods with an extensive degree of morpho-
logical and colour variation (Rudman, 1971, 1972a, b, c, 1974,
1978;Gosliner,1980, 2008). The family contains seven recog-
nized genera and approximately 80 species worldwide distribu-
ted in tropical, sub-tropical and temperate shores. They are
mostly found in soft bottom habitats and alga tufts around
rocky shores, coral reefs and seagrass meadows (Thompson,
1977;Martı
´
nez et al., 1993;Nakano,2004;Valde
´
s et al., 2006;
Gosliner et al., 2008;Camacho-Garcı
´
a et al., 2013; Costello
et al., 2013; Bouchet, 2014;Malaquias,2014).
A recent phylogenetic hypothesis of the Aglajidae confirmed
the monophyly of the genera Aglaja, Melanochlamys,
Nakamigawaia, Navanax, Odontoglaja and Philinopsis but sug-
gested the paraphyly of Chelidonura which branched in three sub-
clades (Camacho-Garcı
´
a et al., 2013). The general morphology
and anatomy of several species in these three subclades are well
known and they all depict similar body plans (Rudman, 1974;
Gosliner, 1980; Yonow, 1992, 1994; Ornelas-Gatdula et al.,
2012). As a consequence, the taxonomic status of Chelidonura is
presently not clear and thus, for the purpose of this research, we
adopted its traditional definition (sensu Burn & Thompson, 1998).
In addition to these seven genera, there has been some
debate about the validity and inclusion in the family
Aglajidae of three other lineages, namely Noalda,
Pseudophiline and Spinoaglaja
. The genus Spinoaglaja was
proposed for western Atlantic species with a spine-like ext en-
sion on the anterior part of the shell (Ortea et al. , 2007), but
Camacho-Garcı
´
a et al. (2013) have regarded it as a synonym
of Philinopsis; the latter authors did not consider Noalda as
part of the Aglajidae, but this remains to be tested in a molecu-
lar phylogenetic framework. Pseudophiline has morphological
similarities with Philine (Gosliner, 1980; Kitao & Habe, 1982)
and the genus was recently ascribed to the family Philinidae
based on the presence of philinid-like gizzard plates and
radula (Chaban, 2011). More recently, the new genus
Migaya was proposed by Ortea et al. (2014) for the western
Atlantic species Aglaja felis, but the validity of this genus
remains to be tested in a phylogenetic framework.
Herbivory is considered the plesiomorphic feeding condi-
tion in the Cephalaspidea (Jensen, 1994; Mikkelsen, 1996;
Go
¨
bbeler & Klussmann-Kolb, 2009; Malaquias et al., 2009),
and carnivory was suggested by Malaquias et al. (2009)to
have arise n independently two or three times in different
lineages. The latter authors have hypothesized that dietary
specialization played a major role in the adaptive radiation
of Cephalaspidea gastropods and that relations between prey
structure, habitat and anatomy were important in the diversi-
fication within each lineage, allowing the development of
more specific predator –prey interactions.
Aglajids show several unique evolutionary traits with poten-
tial relevance for feeding strategies and diversification, such as
the reduction and posterior internalization of the shell, simpli-
fication of the digestive system (e.g. loss of hard mastication
Corresponding author:
A. Zamora-Silva
Email: Andrea.Zamora@um.uib.no
1
Journal of the Marine Biological Association of the United Kingdom, page 1 of 12. # Marine Biological Association of the United Kingdom, 2015
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/3.0/), which permits
unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited.
doi:10.1017/S0025315415000739
structures like the radula and gastric plates in the large majority
of species), development and thickening of the buccal bulb and
gizzard, secretion of deterrent chemicals, and cephalization of
sensorial organs (Rudman, 1972a, b, c, 1978;Gosliner,1980;
Sleeper et al., 1980; Leonard & Lukowiak, 1984;Wa
¨
gele &
Klussmann-Kolb, 2005;Cruz-Rivera,2011).
Several sensory structures in gastropods (e.g. eyes, anterior
lateral fold s, Hancock’s organs, cephalic bristles, labial palps)
are known to aid in tracking mucous trails (Kohn, 1983) and
for example, Paine (1963, 1965) and Leonard & Lukowiak
(1984) have demonstrated that active predation in Navanax
involves mucous trail and chemoreception. The few empirical
data available on the crawling speed of aglajids suggests that
they are among the fastest moving sea slugs (Turner, 1978).
The size of the buccal bulb and its ability of eversion are also
important features in feeding: in Aglaja, Melanochlamys,
Navanax and Philinopsis, the buccal bulb occupies almost half
of the body length; while in Chelidonura, Nakamigawaia and
Odontoglaja it is reduced to one-fifth of the body (Rudman,
1971). Two different forms of the buccal bulb prevail in
Philinopsis: the typical bulbous shape (e.g. P. taronga, P. orientalis)
that is also present in Aglaja, Melanochlamys and Navanax;anda
tubular variation (e.g. P. depicta, P. pilsbryi) (Rudman, 1971,
1972a, b, c, 1974, 1978)(Figure 1A–C). The buccal bulb in
Aglaja and Navanax can evert completely, whereas this ability is
absent in Chelidonura, Nakamigawaia, Melanochlamys and
Philinopsis (Rudman, 1971, 1974;Gosliner,1980, 1994).
The genus Navanax
feed upon other cephalaspideans
including conspecifics, sacoglosans, anaspideans, nudi-
branchs, caenogastropods, polychaetes, crustaceans and
small fish (Paine, 1963, 1965; Blair & Seapy, 1972; Gosliner,
1980; Leonard & Lukowiak, 1984; Pennings, 1990; Pennings
et al., 2001; Korb, 2003); Philinopsis and Melanochlamys
feed upon cephalaspideans and polychaetes (Rudman,
1972a, b,Go
¨
bbeler & Klussmann-Kolb, 2009); Chelidonura
upon flatworms (Gosliner, 1987, 1994; Yonow, 1992;
Mangubhai, 2007); while Odontoglaja feeds on polychaetes
and bivalves (Rudman, 1978;Wa
¨
gele & Klussmann-Kolb,
2005; Lobo-da-Cunha et al., 2009). No data are available on
the diet of Aglaja and Nakamigawaia.
In this study we provide the first assessment of the dietary
habits of Aglajidae sea slugs based on a comprehensive review
of the literature and examination of gut contents of specimens
representing the generic diversity of the family. We discuss
our findings in relation to the distinctive anatomical, ecologic-
al and behavioural adaptations of these slugs.
MATERIALS AND METHODS
Ninety-two specimens belonging to 32 species of Aglajidae were
dissected and their gut contents removed and examined
(Tabl e 1). Buccal bulb, oesophagus, intestine, and digestive gland
were extracted and opened and the contents spread in Petri
dishes filled with 70% ethanol and identified to the lowest possible
taxonomic level using stereo, compound and scanning electron
microscopy (SEM). Food items were mounted on SEM metallic
stubs and coated with gold-palladium. Macrophotography was
also used when convenient (Figures 2–4). In addition to gut
content analyses, we revised the literature for records of
Aglajidae food preferences in the wild (Table 2).
Food items were classified in ‘sessile’ and ‘vagile’ according
to their mobility capa cities (Menge et al., 1994;Wa
¨
gele, 2004;
Madden et al., 2008) and an estimate of food preference
(vagile vs sessile) was inferred based on the total diversity of
food items recognized during this study and from literature
records presented in Table 2.
RESULTS
Food items were found in the gut of 11 out of the 32 species
studied and in 24 of the 92 specimens dissected, correspond-
ing to 26% of the specimens analysed (Table 1): one specimen
of Aglaja and Nakamigawaia, three specimens of Navanax,
four specimens of Chelidonura, Philinopsis and Odontoglaja,
and seven of Melanochlamys.
Based on literature records and our own results, 70 differ-
ent food items were re cognized belonging to 20 major taxo-
nomic groups, with vagile organisms accounting for 94%
(¼66 food items) of the diet composition. Carnivory is
Fig. 1. Diagrammatic representation of the digestive system in Aglajidae and SEM image of the radula of Odontoglaja guamensis: (A) massive buccal bulb of
Aglaja, Melanochlamys, Navanax and Philinopsis; (B) tubular buccal bulb variation of Philinopsis; (C) reduced buccal bulb in Chelidonura, Nakamigawaia and
Odontoglaja; (D) radula of O. guamensis. (m) mouth; (bb) buccal bulb; (sg) salivary glands; (oe) oesophagus; (g) gut; (dg) digestive gland; (a) anus. Scale bar:
100 mm.
2 andreazamora-silvaandmanuelanto
’
nio e. malaquias
Table 1. List of Aglajidae species dissected for gut contents. Numbers in brackets are the total number of specimens dissected. (ZMBN – Natural History Collections, University Museum of Bergen, Norway; WAM –
Western Australian Museum; USNM – United States National Museum, Smithsonian; CNMO – Coleccio
´
n Nacional de Moluscos, National Autonomous University of Me
´
xico; NMVF – Museum Victoria, Australia).
Species dissected [no. of specimens dissected] Species with gut content No. of specimens with gut content Voucher No Food item No. of food items in the gut
Aglaja Renier, 1807
A. felis Er. Marcus & Ev. Marcus, 1970 [11] A. felis 1 of 11 ZMBN 84913 Foraminiferans 4
A. tricolorata Renier, 1807 [1]
Aglaja sp. [3]
Chelidonura A. Adams, 1850
C. africana Pruvot–Fol, 1953 [1] C. fulvipunctata 1 of 6 WAM S80134 Nuculidae (Bivalvia) 1
C. amoena Bergh, 1905 [2] C. inornata 1 of 4 ZMBM 94027 Chelidonura inornata 1
C. berolina Er. Marcus & Ev. Marcus, 1970 [2] (Cephalaspidea gastropods)
C. cubana Ortea & Martı
´
nez, 1997 [2] Stylocheilus longicaudus 1
C. electra Rudman, 1970 [1] (Anaspidea gastropods)
C. fulvipunctata Baba, 1938 [6]
C. hirundinina (Quoy & Gaimard, 1833) [1] C. sandrana 2 of 4 ZMBM 94028 Philinopsis sp. 1
C. inornata Baba, 1949 [4] (Cephalaspidea gastropods)
C. pallida Risbec, 1951 [1] Retusa sp. 1
C. sandrana Rudman, 1973 [4] (Cephalaspidea gastropods)
C. tsurugensis Baba & Abe, 1964 [1]
C. varians Eliot, 1903 [1]
Chelidonura sp. [2]
Melanochlamys Cheeseman, 1881
M. cylindrica Cheeseman, 1881 [1] M. diomedea 7 of 8 USNM Enoploidea (Nematoda) 5
M. diomedea (Bergh, 1893) [8] 771859 Kinorhyncha 2
Aciculata (Polychaeta) 2
Nakamigawaia Kuroda & Habe, 1961
N. spiralis Kuroda & Habe, 1961 [7] N. spiralis 1 of 7 ZMBM 94029 Foraminiferans 3
Nakamigawaia sp. [2]
Navanax Pilsbry, 1895
N. aenigmaticus (Bergh, 1893) [3] N. aenigmaticus 2 of 3 USNM 734396 Bulla punctulata
(Cephalaspidea gastropods)
3
N. inermis (J.G. Cooper, 1863) [4] N. inermis 1 of 4 CNMO 1818 Gobiidae (Pisces) 1
N. orbygnianus (Rochebrune, 1881) [2]
Noalda Iredale, 1936
N. exigua (Hedley, 1912) [1] – – – – –
Odontoglaja Rudman, 1978
O. guamensis Rudman, 1978 [4] O. guamensis 4 of 4 ZMBM 94030 Philine sp. 2
(Cephalaspidea gastropods)
Isopoda 1
(Crustacea, Eumalacostraca)
Holothuroidea 1
(Echinodermata)
Philinopsis Pease, 1860
P. depicta Pease, 1860 [3] P. depicta 2 of 3 ZMBM 94031 Facelinidae 1
P. falciphallus Gosliner, 2011 [5] (Nudibranchia gastropods)
Continued
diet preferences in aglajidae 3
confirmed as the only feeding strategy in Aglajidae. The sessile
organisms recognized in the gut of aglajids were bivalves, for-
aminiferans and sponge spicul es (Table 2).
Foraminiferans were the only food item found in the gut
contents of Aglaja and Nakamigawaia, whereas Navanax
yielded the most diverse assemblage of food items, namely
sponges, cephalaspidean gastropods, nudibranch gastrop ods,
sacoglossan gastropods, caenogastropods, annelids, crusta-
ceans and fish.
Field observations showed that Chelidonura inornata feed
upon conspecifics and Navanax inermis was observed sucking
in juveniles of Aplysia sp. (A. Zamora, personal observation).
DISCUSSION
With the exception of the studies by Paine (1963, 1965) on the
diet of the genus Navanax, knowledge about dietary prefer-
ences of aglajid slugs is based on sparse records included in
general works about the diversit y or morphological aspects
of the Aglajidae (e.g. Tchang-Si, 1934; Marcus, 1961;
Marcus & Marcus, 1966; Blair & Seapy, 1972; Rudman,
1972a, b, 1978; Pennings, 1990; Pennings et al., 2001;
Padilla et al., 2010; Gosliner, 2011; Camacho-Garcı
´
a et al.,
2013; see Table 2). This study is the first comprehensive
account dedicated to understand the trophic interactions of
Aglajidae slugs as a whole.
The rather low percentage of slugs found with food
remains in the gut (26%) may be partly explained by the
fact that some aglajids regurgitate the hard parts of prey
items after digestion when those seem to be above a certain
threshold size. This behaviour was documented by Rudman
(1971, 1972a) for the species Philinopsis speciosa, which he
observed regurgitating several empty shells of the gastropod
Bulla ampulla after 2 –3 h of capture. Aglajids do not have a
crushing gizzard with plates and in some cases large shells
are likely too difficult to be carried along the digestive tract
and end up, therefore, being regurgitated. However, Paine
(1963) and Pennings (1990) have demonstrated that in the
large sized-body aglajid species Navanax inermis (average
adult size c. 40 mm; Leonard & Lukowiak, 1984), complete
shells of small ‘prosobranchs’ and ‘opisthobranchs’ (e.g.
Aplysia, Bulla) and hard-pa rts of sea slugs (e.g. radulae,
jaws, shells) can be defecated unaltered.
A striking result of this research is the recognition that
aglajids feed nearly exclusively upon vagile prey (94% of
food items; Tabl e 2). Motile organisms secrete mucus to aid
in crawling or as a protective mechan ism (e.g. opisthobranchs,
nematodes, platyhelminths, annelids, gastropods) (Brusca &
Brusca, 2003; Hickman et al., 1993), leaving behind mucous
trails that can be located and traced by aglajids using their
sensorial organs (Paine, 1965; Kohn, 1983; Davies &
Blackwell, 2007; Terrence et al., 2013).
The genera Navanax and Phili nopsis include relatively
large animals (adult size over 10 mm in most cases) with a
massive buccal bulb that occupies about half of the body
cavity (Rudman, 1972a, 1974)(Figure 1). These slugs are
active crawlers and can feed upon larger prey (e.g. fish,
bulloid gastropods, polychaetes, flatworms, crustaceans, cte-
nophores and other sea slugs; Table 3) by a rapid, partial or
complete eversion of the buccal bulb. Paine (1963) documen-
ted cannibalism in Navanax (N. inermis) but only between
animals of dissimilar size and when those attempted to
Table 1. Continued
Species dissected [no. of specimens dissected] Species with gut content No. of specimens with gut content Voucher No Food item No. of food items in the gut
P. gardineri (Eliot, 1903) [1] Rissoina sp.
(Caenogastropoda)
1
P. gigliolii (Tapparone–Canefri, 1874) [1]
P. orientalis (Baba, 1949) [1] P. taronga 2 of 3 NMVF K02 Haminoea sp. 1
P. reticulata (Eliot, 1903) [1] (Cephalaspidea gastropods)
P. speciosa Pease, 1860 [3] Melanochlamys cylindrica 1
P. taronga (Allan, 1933) [3] (Cephalaspidea gastropods)
4 andreazamora-silvaandmanuelanto
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nio e. malaquias
mate. The diet of N. inermis is by far the best known among
aglajids as a result of the long-term and dedicated studies by
Paine (1963, 1965; see Table 2). These studies seem to indicate
that the genus Navanax is the most generalist among the
Aglajidae, but of course this can be the result of the uneven
amount of data collected for this genus when compared
with the others. The presence of sponge spicules found by
us in the gut of Navanax is likely the result of random
ingestion.
On the other hand, Chelidonura, Melanochlamys and
Odontoglaja species are on average smaller slugs (adult size
less than 10 mm in most cases; exceptions are common in
Chelidonura) that have comparatively a reduced and
non-eversible buccal bulb (the latter is partially eversible in
Odontoglaja) (Rudman, 1972b, 1974; Figure 1; Table 3).
Chelidonura seems to have a preference for epifaunal organ-
isms (e.g. flatworms, slugs, shelled gastropods), whereas
Melanochlamys feed predominantly upon infaunal prey such
Fig. 2. Scanning electron micrographs of food items found in the digestive tract of Aglajidae specimens: (A) residues of foraminiferans in Aglaja felis ZMBN
84913; (B) valve of Nuculidae bivalve in Chelidonura fulvipunctata WAM S80134; (C) jaws of Facelinidae nudibranch in Philinopsis depicta ZMBM 94031;
(D) radula of Facelinidae nudibranch in Philinopsis depicta ZMBM 94031; (E) detail of radula of Facelinidae nudibranch in Philinopsis depicta ZMBM 94031;
(F) shell of Haminoea sp. in Philinopsis taronga NMVF K02; (G) gizzard plates of Haminoea sp. in Philinopsis taronga NMVF K02. Scale bars A and E:
200 mm; B and F: 100 mm; C, D, and G: 20 mm.
diet preferences in aglajidae 5
as polychaetes, nemerteans, nematodes and kinorhynchs
(Table 3).
Odontoglaja, the only confirmed genus with radula (Gosliner
et al., 2008; Figure 1; referred to a possible Chelidonura with
a vestigial radula), which is well developed with strong
bicuspid lateral teeth (Gosliner et al., 2008; Figure 1), has
apparently a preference for organisms with thicker dermis
such as crustaceans, ?holothurians, and polychaetes (Hickman
et al., 1993; Table 3).
Aglaja and Nakamigawaia are genera for which nothing
was previously known about their diet. Most species have an
average adult size over 10 mm (Rudman, 1972c; Baba,
1985), but based on our results it is not possible to ascertain
where the sole presence of foraminiferans found in the gut
reflects a dietary preference or results from accidental inges-
tion. Because of average size, anatomical configuration of
the digestive tract, and crawling capacities of these snails
(Rudman, 1972c; Baba, 1985; Gosliner et al., 2008; Figure 1;
Fig. 3. Scanning electron micrographs of food items found in the digestive tract of Aglajidae specimens: (A) shell of Bulla punctulata in Navanax inermis CNMO
1818; (B) radula of B. punctulata in Navanax inermis CNMO 1818; (C) gizzard plates of B. punctulata in Navanax inermis CNMO 1818; (D) shell of Philine sp. in
Odontoglaja guamensis ZMBM 94030; (E) gizzard plates of Philine sp. in Odontoglaja guamensis ZMBM 94030; (F) Aciculata polychaete in Melanochlamys
diomedea USNM 771859; (G) detail of the parapodia of Aciculata polychaetes in Melanochlamys diomedea USNM 771859. Scale bars A: 1 mm; B, C and D:
200 mm; E and G: 20 mm; F: 100 mm.
6 andreazamora-silvaandmanuelanto
’
nio e. malaquias
Tables 2 & 3), our expectation was to find a diet composed by
several motile invertebrates.
Malaquias et al. (2009) mapped the diet of most lineages of
cephaslaspids onto a molecular phylogeny of the group and
have suggested that dietary specialization played a major
role in the adaptive radiation of these gastropods. Our
results reinforced the view that Aglajidae slugs are the only
active hunter group of cephalaspids and the only one to be
specialized on motile prey (Malaquias et al., 2009;Go
¨
bbeler
& Klussmann-Kolb, 2009).
ACKNOWLEDGEMENTS
We are indebted to A. Cosgrove-Wilke (Western Australian
Museum), E. Naranjo-Garcı
´
a (Coleccio
´
n Nacional de
Moluscos, UNAM-Me
´
xico), J. Chuk (Museum Victoria,
Australia), N. Anthes (University of Tu¨bingen), K. Jensen
and O. Tendal (Zoologisk Museum, Copenhagen),
T. Nickens (Smithsonian Institution, National Museum of
Natural History), and M. Caballer (Muse
´
um national
d
1
Histoire naturelle, Paris) for providing specimens for this
Fig. 4. Scanning electron micrographs of food items found in the digestive tract of Aglajidae specimens: (A) Kynorhyncha sp. in Melanochlamys diomedea USNM
771859; (B) ?exoskeleton of Isopoda in Odontoglaja guamensis ZMBM 94030; (C) Enoploidea nematodes in Melanochlamys diomedea USNM 771859; (D) detail of
the mouth of the nematodes in Melanochlamys diomedea USNM 771859; (E) ?fragment of a spicule of Holothuria in Odontoglaja guamensis ZMBM 94030; (F)
complete specimen of Gobiidae fish in Navanax inermis CNMO 1818. Scale bars A: 20 mm; B: 30 mm: C and E: 100 mm; D: 10 mm, F: 5 mm.
diet preferences in aglajidae 7
Table 2. Review of the diet of Aglajidae based on literature records and novel data (based on animals collected in the wild).
Species Food item Prey ecology References
Aglaja Renier, 1807
A. felis Er. Marcus & Ev. Marcus, 1970 - Foraminiferans Sessile Present study
Chelidonura A. Adams, 1850
C. alisonae Gosliner, 2011 - Convoluta acoels flatworms (Acoelomorpha) Vagile Gosliner (2011)
C. fulvipunctata Baba, 1938 - Nuculidae (Bivalvia) Sessile Present study
C. hirudinina (Quoy & Gaimard, 1833) - Free living flatworms (?Acoelomorpha/Platyhelminthes) Vagile Gosliner (1987)
Cruz-Rivera (2011)
Kohn (1983)
C. inornata Baba, 1949 - Chelidonura inornata (Cephalaspidea gastropods)
- Stylocheilus longicaudus (Anaspidea gastropods)
All vagile Rudman, 1974
Present study
C. punctata Eliot, 1903 - Acoels flatworms Vagile Mangubhai (2007)
C. sandrana Rudman, 1973 - Philinopsis sp.
- Retusa sp. (Cephalaspidea gastropods)
All vagile Present study
C. varians Eliot, 1903 - Acoels flatworms (Acoelomorpha) Vagile Yonow (1992, 1994)
Melanochlamys Cheeseman, 1881
M. cylindrica Cheeseman, 1881 - Polychaeta
- Nemertea
All vagile Rudman (1971, 1972b, c)
M. diomedea (Bergh, 1893) - Enoploidea (Nematoda)
- Kinorhyncha
- Aciculata (Polychaeta)
All vagile Present study
Nakamigawaia Kuroda & Habe, 1961
N. spiralis Kuroda & Habe, 1961 - Foraminiferans Sessile Present study
Navanax Pilsbry, 1895
N. aenigmaticus (Bergh, 1893) - Haliclona sp. (Porifera)
- Tethya sp. (Porifera)
- Bulla sp.
- Bulla punctulata (Cephalaspidea gastropods)
Sessile
Vagile
Ev. Marcus & Er Marcus (1966)
Padilla et al. (2010)
Present study
N. gemmatus
(Mo
¨
rch, 1863) - Platyhelminthes
- Elysia crispata (Sacoglossa gastropods)
All vagile Thompson (1976, 1977)
Gosliner, 1980
N. inermis (J. G. Cooper, 1863) - Aplysia californica (Anaspidea gastropods)
- Bulla punctulata
- B. gouldiana
- Haminoea virescens
- Navanax inermis (Cephalaspidea gastropods)
- Elysia sp. (Sacoglossa gastropods)
- Barleeia sp. (Caenogastropoda)
- Cystiscus sp. (Neogastropoda)
- Gobiidae (Pisces)
All vagile Paine (1963, 1965)
Emlen (1966)
Blair & Seapy (1972)
Gosliner (1980; 1994)
Sleeper, et al. (1980)
Leonard & Lukowiak (1984)
Pennings (1990)
Pennings et al. (2001)
Korb (2003)
Present study
N. polyalphos (Gosliner & Williams, 1972) - Haminoea sp. (Cephalaspidea gastropods) Vagile Gosliner & Williams (1972)
8 andreazamora-silvaandmanuelanto
’
nio e. malaquias
Odontoglaja Rudman, 1978
O. guamensis Rudman, 1978 - Polychaeta
- Philine sp. (Cephalaspidea gastropods)
- Isopoda (Crustacea)
- Holothuroidea (Echinodermata)
Vagile Rudman (1978)
Present study
O. mosaica Gosliner, 2011 - Benthic copepods (Crustacea) Vagile Gosliner (2011)
Philinopsis Pease, 1860
P. ctenophoraphaga Gosliner, 2011 - Coeloplana (Benthoplana) meteoris (Benthic ctenophores) Vagile Gosliner (2011)
P. depicta Pease, 1860 - Polychaeta
- Philine quadripartita
- P. scabra (Cephalaspidea gastropods)
- Facelinidae (Nudibranchia gastropods)
- Rissoina sp. (Caenogastropoda)
All vagile Marcus (1961)
Gosliner (1980)
Chiu, 1990
Lobo-da-Cunha et al. (2009)
Lobo-da-Cunha et al. (2011)
Present study
P. falciphallus Gosliner 2011 - Polyclad flatworms (Platyhelminthes) Vagile Gosliner (2011)
P. pilsbryi (Eliot, 1900) - Small opisthobranchs (Opisthobranchia gastropods) Vagile Go
¨
bbeler & Klussmann–Kolb (2009)
P. minor (Tchang-Si, 1934) - Small molluscs Vagile Tchang-Si (1934)
P. speciosa Pease, 1860 - Aliculastrum cylindricum
- Bulla ampulla
- Chelidonura sandrana
- Haminoea sp. (Cephalaspidea gastropods)
- Aplysia parvula (Anaspidea gastropods)
- Ringicula sp. (Heterobranchia gastropods)
All vagile Rudman (1972a)
Gosliner (1980)
Yonow (1992)
P. taronga (Allan, 1933) - Amalda sp. (Caenogastropoda)
- Haminoea sp.
- Haminoea zelandiae
- Melanochlamys cylindrica
- Philine auriformis (Cephalaspidea gastropods)
All vagile Rudman (1972a)
Present study
diet preferences in aglajidae 9
study. We also thank J. L. Cervera (University of Ca
´
diz),
N. Budaeva (University Museum of Bergen, Norway) and
P. Valentich-Scott (Santa Barbara Museum of Natural
History) for helping with identification of some food items.
We are grateful to E. Erichsen (University of Bergen) for his
support with the electron microscopy sessions. M. Caballer
made valuable comments on this paper.
FINANCIAL SUPPORT
This work was funded through a doctoral grant given to the
first author by the Consejo Nacional de Ciencia y
Tecnologı
´
a (CONACYT-Me
´
xico), fellowship BAZS/188890/
2010. Additionally, this research benefited from specimens
gathered through visits of the second author to European
natural history museums funded by the SYNTHESYS
Project, http://www.synthesys.info/, which is financed by the
European Community Research Infrastructure Action under
the FP7 ‘Capacities’ Program.
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Correspondence should be addressed to:
A. Zamora-Silva
Phylogenetic Systematics and Evolution Research Group,
Department of Natural History, University Museum of
Bergen, University of Bergen, PB 7800, 5020-Bergen, Norway
email: Andrea.Zamora@um.uib.no
12 andrea zamora-silva and manuel anto
’
nio e. malaquias
