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New record of Azurina intercrusma (Evermann & Radcliffe, 1917) (Ovalentaria incertae sedis, Pomacentridae) and confirmation of Scuticaria tigrina (Lesson, 1828) (Anguilliformes, Muraenidae) in the Galápagos Islands

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Abstract

Herein we provide the first published records for Azurina intercrusma and a correction of previous Scuticaria tigrina records within the Galápagos Marine Reserve. The former had not previously been reported north of the southern Ecuadorian coastline and represents a significant step outside of its known distribution for this cold-water species. Scuticaria tigrina had been mentioned in previous literature as present, but its inclusion appears to have been in error; we confirm its presence as a vagrant and provide evidence of live observations in different parts of the archipelago.
NOTES ON GEOGRAPHIC DISTRIBUTION
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Check List 19 (5): 611–620.
https://doi.org/10.15560/19.5.611
5
19
New record of Azurina intercrusma (Evermann & Radclie, 1917)
(Ovalentaria incertae sedis, Pomacentridae) and conrmation of
Scuticaria tigrina (Lesson, 1828) (Anguilliformes, Muraenidae) in
the Galápagos Islands
W B-S1*, I K1, J G2, S B1
1 Charles Darwin Research Station, Charles Darwin Foundation, Santa Cruz, Galápagos, Ecuador WBS: billy.benstedsmith@fcdar-
win.org.ec https://orcid.org/0009-0001-6848-7594 • IK: inti.keith@fcdarwin.org.ec https://orcid.org/0000-0001-9313-833X
SB: stuart.banks@fcdarwin.org.ec https://orcid.org/0009-0007-5015-0903
2 East Pacic Corridor Alliance, Tavernier, FL, USA • JG: jgrove@epcafoundation.org https://orcid.org/0000-0002-7110-2931
* Corresponding author
Abstract. Herein we provide the rst published records for Azurina intercrusma and a correction of previous
Scuticaria tigrina records within the Galápagos Marine Reserve. e former had not previously been reported
north of the southern Ecuadorian coastline and represents a signicant step outside of its known distribution for
this cold-water species. Scuticaria tigrina had been mentioned in previous literature as present, but its inclusion
appears to have been in error; we conrm its presence as a vagrant and provide evidence of live observations in
dierent parts of the archipelago.
Keywords. Citizen science, Eastern Tropical Pacic, new record, reef-eel, reef-sh, scuba diving, subtidal moni-
toring
Academic editor: Arturo Angulo
Received 6 June 2023, accepted 23 August 2023, published 18 September 2023
Bensted-Smith W, Keith I, Grove J, Banks S (2023) New record of Azurina intercrusma (Evermann & Radclie, 1917) (Ovalentaria
incertae sedis, Pomacentr idae) and conrmation of Scuticar ia tigrina (Lesson, 1828) (Angui lliformes, Muraenidae) in the G alápagos
Islands. Check List 19 (5): 611–620. https://doi.org/10.15560/19.5.611
Introduction
e Galápagos are famous for their abundant native
and endemic marine wildlife (Bustamante et al. 2000)
and the dangers of introduction of non-native species
through anthropogenic vectors (Keith et al. 2016; Carl-
ton et al. 2019); however, what is less well-document-
ed is the ux of “vagrant” marine species through the
islands’ waters (McCosker and Rosenblatt 2010). Much
of the ocean’s fauna and ora have a pelagic larval
stage during their development (Orton 1953; Strath-
mann 1993) and this, combined with the oceanic cur-
rents interacting with the Eastern Tropical Pacic
(ETP) (Kessler 2006), occasionally leads to rare or pre-
viously unseen species appearing in the archipelago.
ese “vagrant” species are usually unable to establish
populations and are just temporary residents on the
islands, such as the butterysh of the Indo-Pacic
which can be observed sporadically along the reefs of
Darwin and Wolf (Fig. 1) (Robertson and Allen 2015).
However, occasionally sucient individuals of a giv-
en species arrive, nd each other, and establish a long-
lasting breeding population, the likelihood of which is
also dependent on the adaptability of the species to the
seasonally changing habitats in the Galápagos (Houve-
naghel 1984; Kessler 2006).
Azurina D.S. Jordan & McGregor in Jordan & Ever-
mann, 1898, belonging to the subfamily Chrominae, is
a genus which has undergone several taxonomic revi-
sions over the past decade and a half. Originally con-
taining only two species, it was considered endemic to
the ETP (Robertson and Allen 2015) and comprised of
612 Check List 19 (5)
damselsh with a continuous lateral line and deeply
forked caudal n (Jordan and Evermann 1896; Heller
and Snodgrass 1903). is classication has since been
superseded by Tang et al. (2021), who assigned 10 spe-
cies to the genus Azurina, among those, and for the
rst time, A. intercrusma (Evermann & Radclie, 1917).
is expanded genus now incorporates all species pre-
viously assigned to Chromis G. Cuvier, 1814 with XII
dorsal-n spines from the Atlantic and Eastern Pacic,
as well as two Indo-West Pacic species with the same
morphological characteristics. Only two species within
the clade dier from this denition, including the pos-
sibly now extinct Galápagos endemic (Edgar et al. 2010;
McCosker and Rosenblatt 2010; Russell and Craig 2013)
A. eupalama Heller & Snodgrass, 1903 (with XII–XIV
dorsal-n spines; Heller and Snodgrass 1903). Azuri-
na intercrusma is one of the species assigned to Azu-
rina but not examined within the study by Tang et al.
(2021) due to it also possessing XII dorsal-n spines
and having an Eastern Pacic distribution (Robertson
and Allen 2015), traits which are shared by only two
species in the subfamily Chrominae, all of which have
been classied as Azurina. is identier, in conjunc-
tion with several other morphological features, led the
authors to assign Chromis intercrusma to Azurina sen-
su lato (Tang et al. 2021).
Prior to the present study, the Galápagos Islands
were known to house only one extant species of Azu-
rina (A. atrilobata (T.N. Gill, 1862)), or two if the afore-
mentioned A. eupalama is considered. ere have been
no records of A. intercrusma in the Galápagos Marine
Reserve (GMR) in any of the principal global sh loca-
tion aggregator databases (FishNet 2 2023; iNaturalist
2023; GBIF 2023; OBIS 2023). In fact, the northernmost
record was in 2021 during an intertidal biodiversity
monitoring (Martínez Panizo et al. 2022) of the Bajo
Copé Marine Reserve (Ministerio del Ambiente 2020)
o the coast of Ecuador at a latitude of 01.8°S, with its
Figure 1. Map of the Galápagos Islands showing the locations at which Azurina intercrusma (A) and Scuticaria tigrina (BD) were
observed. Map created by Emily McFarling and Johny Mazón (CDF).
Bensted-Smith et al. | Azurina intercrusma and Scuticaria tigrina in the Galápagos 613
normal range extending from the southern coast of
Ecuador south to Chile between depths of 0 and 35 m
(Robertson and Allen 2015).
On 7 April 2022, W. Bensted-Smith observed a sin-
gle juvenile of A. intercrusma, ~7 cm long, swimming
amongst the rocks (Fig. 2A, B) at a depth of 6 m dur-
ing a Subtidal Ecological Monitoring (Banks 2014)
scuba dive at the tourist site of Punta Moreno on the
southwest coast of Isabela Island (Fig. 1A). It was not-
ed that this individual was swimming alongside a sim-
ilar-looking A. atrilobata, and it could be dierentiated
from this species due to the lack of a prominent white
spot just below the end of the base of the so dorsal
n, which is characteristic of A. atrilobata (Fig. 2C).
No other individuals were noted at any of the other 52
dive sites along the coastlines of western Isabela or the
neighbouring island of Fernandina during that moni-
toring eort.
e morays of the world (Muraenidae) are divided
into two subfamilies, Muraeninae and Uropterygiinae,
the latter of which contains ve genera (Loh et al. 2008).
All ve can be found within Pacic waters, but only
Anarchias, Uropterygius, and Scuticaria are present
in the ETP (GBIF 2023; OBIS 2023). e genus Scuti-
caria Jordan & Snyder, 1901, originally a subgenus of
Uropterygius Rüppell, 1838, was only recognised as its
own genus in 1997 (Böhlke and McCosker 1997) and
includes just two species, S. tigrina (Lesson, 1828) and
S. okinawae (Jordan & Snyder, 1901). Scuticaria tigrina
is a widely distributed species, spanning the Indo-Pacif-
ic, and yet relatively little is known about its population
trends, ecology, and natural history due to its nocturnal
nature. In fact, no S. tigrina leptocephali were identied
until 2012, when a genetic and morphometric analysis
of several collected from southern Japan revealed they
pertained to this species (Tawa et al. 2012).
e known range of this species within the ETP
stretches from the southwestern Gulf of California to
the coast of Panama (López and Bussing 1964; Rosen-
blatt et al. 1972; McCosker and Rosenblatt 1995; Robert-
son and Allen 2015). Its presence has also been reported
on several oceanic islands closer to the GMR, such as
Cocos Island (Robertson and Allen 2015) and possi-
bly Malpelo (Bessudo 2021; Robertson pers. comm.
2022). However, excluding a perhaps mistaken record
by Grove and Lavenberg (1997), which appears to have
led to its inclusion in the publications of McCosker and
Rosenblatt (2010) and, by extension, Dale et al. (2021),
there is no published evidence for the occurrence of the
species in the Galápagos Archipelago.
e rst photographic record of S. tigrina in the
Galápagos Islands (Fig. 3C) was by S. Tonge on 11
August 1988, of a dead individual on a beach of Rábi-
da Island (Fig. 1). When alive, the species is known to
inhabit rocky and rubble bottoms on reefs (Robertson
and Allen 2015), which is indeed where it was encoun-
tered by W. Bensted-Smith on 28 March 2021 near Pun-
ta Moreno, Isabela Island, at a depth of 15 m (Fig. 3A),
whilst the third encounter was in the crevasse of a lava
rock wall on Champion Island o the coast of Floreana
by N. Tirado on 31 March 2022 (Fig. 3B). e latter
two observations were both made during the Charles
Darwin Foundation Subtidal Ecological Monitoring
Program and are recorded within the datasets. No fur-
ther sightings of the species have been reported despite
extensive monitoring eorts each year.
Methods
e species listed within this paper were all observed
during subtidal surveys as part of the Subtidal Ecologi-
cal Monitoring program which is undertaken annu-
ally across the dierent bioregions of the Galápagos
Marine Reserve (Edgar et al. 2004; Kislik et al. 2017)
with the aim of examining trends in subtidal commu-
nities during the warm season months experienced
by the archipelago between diagnostic sites and years.
is eort is undertaken by trained researchers of the
Figure 2. Azurina species in the Galápagos. A, B. A. intercrusma.
Side view of juvenile at Punta Moreno, Isabela Island, Galápa-
gos on 7 April 2022 at a depth of 6 m. Screenshots of video by
W. Bensted-Smith. C. A. atrilobata. Side view for comparison;
photo taken by Allison Estape.
614 Check List 19 (5)
Figure 4. Schematic of a 50 m subtidal transect analogous to the Reef Life Survey methodology with the dierence that sessile
biota point interception quadrats are scored in-situ (Banks 2014).
Figure 3. Scuticaria tigrina. A. Head, frontal and side view. B. Head and frontal view. At Punta Moreno of Isabela Island, Galápagos
on 28 March 2021, at a depth of 15 m. Screenshots of video by W. Bensted-Smith. C. Full-body side view at Rábida Island o
Santiago Island, Galápagos on 11 October 1988, onshore, photo by S. Tonge. D. Body side view at Champion Island o Floreana
Island, Galápagos on 31 March 2022, at a depth of 15 m, photo by N. Tirado.
Bensted-Smith et al. | Azurina intercrusma and Scuticaria tigrina in the Galápagos 615
Charles Darwin Research Station (CDRS) together with
Galápagos National Park Rangers and covers 63 diag-
nostic coastal sites, across nine islands, at which non-
xed 50 m transects are laid along two standard depth
strata (15 m and 6 m) usually parallel to the coastline
(Banks 2014). e subtidal monitoring process follows
the methods set out by Edgar et al. (2004) and Banks
(2014b), with four monitored groups surveyed by three
trained divers each performing an authorised non-
invasive visual census.
Within the demersal sh and coastal vertebrates
group, the diver must complete an along-track visual
census which encompasses a 1250 m3 volume of water
on each side of the transect and is repeated for both
depths (Fig. 4) (Banks et al. 2016). During the return-
pass (coastal side of transect in Fig. 1) of each transect,
special focus is given to small and cryptic species which
may not have been detected in the rst pass (Banks
2014); it was during these return passes when the pres-
ence of Azurina intercrusma and Scuticaria tigrina
were observed and recorded.
Results
Azurina intercrusma (Evermann & Radclie 1917)
Photographic record. ECUADOR – Galápagos • Isa-
bela, Punta Moreno; 00.703°S, 091.331°W; 6 m depth;
07.IV.2022; W. Bensted-Smith obs.; 1 individual photo-
graphed.
Identication. Azurina intercrusma is a relatively large
damselsh with a maximum known length of 290
mm, although individuals of ~150 mm TL are more
commonly observed (Prado and Béarez 2004; Robert-
son and Allen 2015). It can oen be confused with the
similar-looking Chromis crusma (Valenciennes, 1833),
which inhabits the same regional coastal waters; how-
ever, these two species can be readily dierentiated by
several morphological dierences, including the num-
ber of dorsal spines, XIII (rarely XIV) on C. crusma,
with the rear shorter than the middle, compared to
Azurina intercrusma’s XII, all equal in length. In addi-
tion, A. intercrusma has distinctly angular ends of the
so dorsal and anal ns, whereas C. crusma’s so dor-
sal and anal ns are broadly rounded (Chirichigno
Fonseca and Vélez Dieguez 1998) and the former’s pec-
torals are of moderate size, oen less than or equal to
the length of the head, while the latter’s are always lon-
ger (Evermann and Radclie 1917). e colouration is
blue-grey on the upper half, fading to paler grey fur-
ther down the anks, whilst the ns are also of a dark-
grey shade.
e juvenile stage of this species has a similarly grey-
coloured head, body, and ns as the adult. However, the
iridescent blue outer edges of the dorsal, pelvic, and anal
ns, as well as the upper and lower edges of the caudal
n (Fig. 5A), make it stand out from other species such
as C. crusma with black edges to the dorsal and anal
ns, and a dark tail n (Fig. 5B). is can cause some
confusion since the outer third of A. intercrusma’s dor-
sum is also black. Both juveniles also have a black spot
at the base of the pectoral n (Robertson and Allen
2015). e congener A. atrilobata also shows a similar
body shape and the black spot at the base of the pec-
toral n; this species is commonly found in Galápagos
waters as well as throughout the ETP, partially over-
lapping with the range of A. intercrusma (Robertson
and Allen 2015; OBIS 2023). Furthermore, A. atriloba-
ta is known to occasionally have faint blue edges to its
dorsal, anal, and pelvic ns, adding to the similarities
between both species. ese two species can be dier-
entiated by the presence of an intensely blackish streak
on the lobe of each caudal n of A. atrilobata and the
prominent white spot just below the end of the base of
the so dorsal n also present on this species (Fig. 2C),
both of which are lacking on both adults and juveniles
of A. intercrusma (Robertson and Allen 2015).
Scuticaria tigrina (Lesson 1828)
Photograp hic records. ECUADOR – Galápagos • Rábi-
da Island; 00.406°S, 090.716°W; 0 m a.s.l.; 11.VIII.1988;
S. Tonge obs.; 1 dead individual photographed • Isa-
bela, Punta Moreno; 00.691°S, 091.318°W; 15 m depth;
28.III.2021; W. Bensted-Smith obs.; 1 individual pho-
tographed • Floreana, Champion; 01.236°S, 090.387°W;
Figure 5. Juveniles, in side view, of Azurina intercrusma and Chromis crusma. A. A. intercrusma, photo by Graham Edgar. B. Chromis
crusma, photo by Rick Stuart-Smith.
616 Check List 19 (5)
15 m depth; 31.III.2022; N. Tirado obs.; 1 individual
photographed.
Identication. Scuticaria tigrina is known to reach siz-
es of 140 cm and inhabits coastlines between depths of
5 and 25 m (Allen and Erdmann 2012; Robertson and
Allen 2015). It has been confused at times with a simi-
lar species, Uropterygius polyspilus (Regan, 1909); both
species have an elongate, almost cylindrical, snake-like
body with similar body colouration and pattern: pale
yellowish grey to russet and covered in yellow-edged
dark blotches along the body and smaller black spots on
the rounded snout and jaws (Fig. 6) (Böhlke and McCo-
sker 1997; Kuiter and Tonozuka 2001; Robertson and
Allen 2015). In addition, both species have short ns
restricted to the tail tip (Böhlke and Randall 2000), and
these similarities have led to these species being con-
fused in at least one case (Gosline 1958). Nevertheless,
there are some key dierences which readily separate
the two species; the position of the anus of S. tigrina
is the clearest identier, far behind the mid-body com-
pared to around the mid-body for U. polyspilus. Identi-
cation underwater can be aided by the shorter snout
and jaw equipped with large, swollen and olive-shaped
posterior nostril tubes on adults of U. polyspilus (Fig.
6D) compared to smaller, straight, and tubular nostrils
on S. tigrina (Fig. 6B) (Böhlke and McCosker 1997).
Discussion
is publication provides the rst photographic evi-
dence of the presence of the Peruvian chromis, Azurina
intercrusma, in the Galápagos Archipelago, as well as
the rst conrmed published record of Scuticaria tig-
rina, whose presence in the islands can be traced back
to 1988 with the rst photo record, albeit of a deceased
specimen. All observations of these species in the Galá-
pagos Archipelago have been of lone individuals with
substantial geographical distance between them, sug-
gesting it is unlikely that they have yet established
breeding populations in the region.
One observation of note is the morphological sim-
ilarity of juvenile A. intercrusma with adult A. atrilo-
bata, as well as the close proximity of the two species
at the location where they were lmed together. Pri-
or to the onset of the 1982–1983 El Niño, the endem-
ic pomacentrid A. eupalama was most oen observed
in heterotypic, plankton-feeding aggregations with A.
atrilobata (Grove and Lavenberg 1997), and Robertson
et al. (2021) suggested that juveniles of Lutjanus inermis
(Peters, 1869) in the Galápagos could possibly remain
undetected in schools of A. atrilobata due to their sem-
blance and only become distinguishable as adults. It
is therefore possible that similar behaviours are being
adopted by solitary or small groups of A. intercrusma
Figure 6. Scuticaria tigrina and Uropterygius polyspilus. A, B. S. tigrina: (A) in side view showing spotted pattern on the body, photo
by Carol Cox; (B) close-up of head features, photo by Allison Estape. C, D. U. polyspilus: (C) side and front view of head and body;
(D) close-up of head features, photos taken by David Rolla.
Bensted-Smith et al. | Azurina intercrusma and Scuticaria tigrina in the Galápagos 617
juveniles which arrive at the islands. Both species are
known to have native ranges which overlap along the
coastlines of southern Ecuador and northern Peru
(Robertson and Allen 2015), which could suggest it is
a common occurrence, but there have been no studies
regarding this activity. Regardless of whether this activ-
ity is common, it is apparent that morphologically sim-
ilar sh will occasionally aggregate (Parrish 1989; Cro
et al. 2003; Tessier et al. 2005), which may be the case
if A. intercrusma juveniles arrive at the Galápagos. e
discovery of A. intercrusma, alongside the recent con-
rmation of the presence of L. inermis in the archipela-
go suggests more care should be taken when recording
schools of Chrominae during monitoring eorts; this
will help identify possible new or rare arrivals from
other regions of the Pacic Ocean. e site is scheduled
to be visited again for monitoring purposes in 2023, at
which time the divers will look closely for this species,
making sure to consider its possible aggregation with
A. intercrusma.
e known native range of A. intercrusma only
extends as far north as the southern coast of Ecuador,
over 1,100 km from the location the juvenile was found,
in an area u nder the inuence of the Humboldt Current,
Chile Coastal Current, Peru Coastal Current, and the
counter currents of the latter two (Kessler 2006; atje
et al. 2008; Chaigneau et al. 2013). During La Niña
years a cold tongue of upwelled waters from the Ant-
arctic extends oshore from northern Peru to the Galá-
pagos Islands, advected oshore by Ekman currents
due to the enhanced trade winds (Fiedler and Talley
2006; Grados et al. 2018). Increased oshore transport
of larvae is thought to occur with the stronger upwell-
ing conditions, although the eect on strong swimming
larvae is diminished (Gaymer et al. 2010). e occur-
rence of this phenomena could create the conditions
necessary for the westward transport of A. intercrusma
larva; members of the same genus are known to have a
planktonic larval duration of over 30 days (Wellington
and Victor 1989; Victor and Wellington 2000) between
the continental and insular coastlines. e observation
was made during a La Niña event which has been ongo-
ing since November 2021 and is the third such event
in a row (Bureau of Meteorology 2022), which suggests
there could be a link between the two. e sh was
found at Punta Moreno along the western shore of Isa-
bela Island (Fig. 1B), on the edge of the Canal Bolivar/
Elizabeth bioregion (Edgar et al. 2004), an area known
to be 5–6°C cooler than nearby islands and highly pro-
ductive due to the upwelling of the Equatorial Under-
current (EUC) bringing colder and nutrient rich waters
from the deep (Houvenaghel 1978; Eden and Timmer-
mann 2004; McCosker and Rosenblatt 2010; Ruiz and
Wol 2011; Wol et al. 2012).
Originating from the Indo-Pacic, an area known as
the heat engine of the world (De Deckker 2016), Scuti-
caria tigrina’s “typical” habitat is much warmer than
that of A. intercru sma; however, both species were found
at the same location (albeit a year apart) known for its
colder waters. is can be explained by the observa-
tion occurring during the warm season of the Galápa-
gos Archipelago in which the EUC upwelling weakens,
along with the Humboldt Current, and the warmer
Panama Current is dominant, raising the water tem-
perature, even in the cold west, by several degrees Cel-
sius (Houvenaghel 1984; Kessler 2006; Schaeer et al.
2008; Glynn et al. 2017). Strong El Niño events, such as
in 1982/83 or 1997/8, are thought to be possible vectors
for the arrival of Indo-Pacic species at fringe islands
of the ETP like the Galápagos, but these are oen only
temporary vagrants and it likely does not represent a
major source of transpacic migration (Robertson et
al. 2004). Another possible advection route is from the
continental coastline and islands of Costa Rica, Pana-
ma, and Colombia, where this species is known to be
present, with increased ow during the warmer season.
As mentioned before, the Galápagos is host to nearly
all species of muraenids recorded from the Indo-Pacif-
ic, be they vagrants or resident populations (McCosker
and Rosenblatt 2010). e potential of muraenid arrival
in the Galápagos could be aided by the greater lepto-
cephali larvae swimming potential and larval life his-
tory of this family, which has enabled them to be highly
dispersive whilst maintaining minimal genetic dier-
entiation between populations (Grove and Lavenberg
1997; Reece et al. 2011). e sporadic observations of S.
tigrina as well as its absence in the major sh collections
carried out in the Galápagos suggest that this species is
likely only a vagrant there.
e record of this species in McCosker and Rosen-
blatt’s (2010) e Fishes of the Galápagos Archipelago:
An Update is unclear. Scuticaria tigrina is mentioned in
only two of the references cited (Rosenblatt et al. 1972;
Grove and Lavenberg 1997), and it is unlikely the spe-
cies was found during the submersible expeditions in
the recent years prior to the publication, since there
is no reference to S. tigrina being found during these
as well as the study area being outside of the species’
depth range (Robertson and Allen 2015). In Grove and
Lavenberg (1997), S. tigrina (as S. tigrinus) is among the
species which they mention has been captured in the
Galápagos archipelago, stating that “only one of the
muraenid eels of Indo-Pacic origin has not: Enchely-
nassa canina”, which remains undetected here (GBIF
2023; OBIS 2023). Nevertheless, no mention is made of
when or where it had been collected, and there appear
to be no records from museum collections conrming
its presence in the islands (FishNet 2 2023; GBIF 2023;
OBIS 2023).
e rst known photographic record of S. tigrina in
the Galápagos Islands is from 1988 and would likely not
have been known to science or species records with-
out the help of citizen science sites such as iNaturalist
(Aristeidou et al. 2021). e fact it was only uploaded
in 2018 shows the importance of sharing private photo
collections through these sites to help identify new spe-
cies and uncommon vagrants.
618 Check List 19 (5)
Both species mentioned are also included within the
recently published list of Galápagos shes (Grove et al.
2022). Scuticaria tigrina is listed therein as a vagrant
based upon the iNaturalist observation by S. Tonge
and personal communications from us, whilst A. inter-
crusma’s inclusion as a vagrant is based solely upon the
record contained herein. Despite these records, this
publication provides the evidence of rst live sightings
of both these species in the Galápagos Islands and is
therefore an important addition to the scientic litera-
ture on the shes of the Galápagos.
Acknowledgements
We thank Ross Robertson and Benjamin Victor for
their help regarding both the identication of these
species as well as the motivation and helpful informa-
tion they have given during the writing of this paper.
We would like to also thank Rashid Cruz for his help
in editing the photos of the species included in this
publication. Furthermore, we thank Emily McFarling
and Johny Mazón for their help creating the map, and
Nathalia Tirado of the Charles Darwin Research Sta-
tion for spotting, photographing, and giving us permis-
sion to use the image of Scuticaria tigrina at Champion
Island (Fig. 3D).
Last but certainly not least, we thank the photogra-
phers who allowed us to use their high-quality imag-
es within this publication: Simon Tonge for providing
his photo of S. tigrina; Allison Estape for her photos of
Azurina atrilobata and S. tigrina; Graham Edgar for his
photo of a juvenile A. intercrusma; Rick Stuart-Smith
for his photo of a juvenile Chromis crusma; Carol Cox
for her photo of S. tigrina; and David Rolla for his pho-
tos of Uropterygius polyspilus.
All authors would like to thank the Galapagos
National Park for granting us authorization to carry
out this investigation (research permit number: PC-07–
22) and the Charles Darwin Foundation for provid-
ing us the opportunity to carry out our research. is
publication is contribution number 2546 of the Charles
Darwin Foundation for the Galapagos Islands.
Author Contributions
Conceptualisation: WBS. Data curation: WBS. Formal
analysis: WBS. Funding acquisition: IK. Investigation:
WBS, IK. Methodology: SB. Resources: IK. Supervi-
sion: IK, JG, SB. Visualisation: WBS. Project admin-
istration: IK. Soware: WBS. Validation: JG. Writing
– original dra: WBS. Writing – review and editing:
WBS, IK, JG, SB.
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