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ZOOTAXA
ISSN 1175-5326 (print edition)
ISSN 1175-5334 (online edition)
Copyright © 2013 Magnolia Press
Zootaxa 3752 (1): 073–085
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Article
73
http://dx.doi.org/10.11646/zootaxa.3752.1.6
http://zoobank.org/urn:lsid:zoobank.org:pub:40BF612C-3B0D-49C6-8212-30ECE57D10D3
Lost and found: recovery of the holotype of the ocellated angelshark, Squatina
tergocellatoides Chen, 1963 (Squatinidae), with comments on western Pacific
squatinids
SUSAN M. THEISS1, * & DAVID A. EBERT2, 3, 4, 5
1Fisheries Queensland; Department of Agriculture, Fisheries and Forestry; Brisbane, Qld 4001 Australia;
E-mail: s.theiss@uq.edu.au
2Pacific Shark Research Center, Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss Landing, CA, 95039, U.S.A.;
E-mail: debert@mlml.calstate.edu
3Research Associate, Department of Ichthyology, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA.
94118, USA
4Research Associate, South African Institute for Aquatic Biodiversity, Private bag 1015, Grahamstown 6140, South Africa
5Shark Research Centre, Iziko – South African Museum, P.O. Box 91, Cape Town, 8000, South Africa
*Corresponding author
Abstract
The ocellated angelshark, Squatina tergocellatoides, Chen, 1963 is redescribed from the holotype, which was thought to
be lost. Its recent recovery has allowed for a revised description, including new data, and comparison to other Western
Pacific squatinids. Squatina tergocellatoides can be distinguished from its congeners by three pairs of prominent large
black spots, each with a diameter greater than eye length; two on each pectoral fin at anterior and posterior angles and one
on each side near the tail base; another three pairs of lesser defined spots, one large spot on base of each dorsal fin and one
located laterally on each side of tail located below first dorsal fin. Ventral surface is uniformly white to cream coloured,
and margins of pectoral fins and tail similar in colour to dorsal side. Pectoral fins with angular lateral apices and rounded
posterior lobe, pelvic fin tips not reaching origin of first dorsal fin, strongly fringed nasal barbels, small inter-orbital space,
head and mouth lengths, broad internarial width and pelvic fin base, a very small pelvic girdle width, and a caudal fin with
triangular ventral lobe greater in length than dorsal lobe. Comments on additional specimens are provided, as well as ob-
servations on biogeography. A review of western Pacific squatinids is also provided.
Key words: Squatinidae, Squatina tergocellatoides, holotype, redescription, Western Pacific, Taiwan
Introduction
The family Squatinidae (Chondrichthyes: Squatiniformes) are a small but highly distinctive group of ‘ray-like’ sharks
comprised of a single genus with approximately 20 valid species (Ebert et al., 2013). Squatinids are a rather undiverse
group with a dorso-ventrally compressed body morphology and appear to have evolved in parallel to the batoids
(Compagno, 1973, 1977). These sharks are typically found on continental shelves and upper slopes in temperate
waters, although some species occur in tropical waters (Ebert & Winton, 2010; White & Sommerville, 2010).
Although squatinids appear to be the sister group to pristiophorids and batoids (de Carvalho, 1996; Shirai, 1996), the
interrelationships between these orders and the Echinorhinidae remain unresolved (Naylor et al., 2012a, 2012b).
The squatinids as a group are very similar morphologically, lacking well-defined morphological characteristics,
and are often misidentified, especially in those regions where multiple members of this genus may occur. A major
problem within the group is the poor original descriptions of many species, compounded by subsequent confusion and
misidentification in the literature. However, taxonomic research over the past decade has helped clarify the regional
status of the group, particularly in the Indo-Western Pacific and southwestern Atlantic (Walsh & Ebert, 2007; Last &
White, 2008; Walsh et al., 2011; Vaz & de Carvalho, 2013), but much work remains to be done. Given that this group
is the subject of target and non-targeted fisheries regionally, and they are known to be a particularly vulnerable group
THEISS & EBERT
74 · Zootaxa 3752 (1) © 2013 Magnolia Press
to over-exploitation (the IUCN Red List of Threatened Species lists 12 species as being near threatened or higher),
improved taxonomic resolution is critical to the conservation and management of this group.
Five valid species are known occur in the western North Pacific (WNP) which include Squatina caillieti Walsh
et al. 2011, S. formosa Shen & Ting 1972, S. japonica Bleeker 1858, S. nebulosa Regan 1906, and S.
tergocellatoides Chen 1963. Recently, Walsh & Ebert (2007) reviewed the WNP squatinids, excluding S. caillieti,
in order to provide more detailed species descriptions and to identify and establish key defining characteristics
between species. Within this review, limited information was available for S. tergocellatoides as the holotype for
this species was thought to be lost (Walsh & Ebert, 2007). However, a survey (March 2012) of museum fish
collections in Taiwan during a biodiversity study of Taiwanese chondrichthyans, the holotype of S. tergocellatoides
was found by Hsuan-Ching (Hans) Ho (National Museum of Marine Biology & Aquarium, Taiwan).
Since the original description of S. tergocellatoides was limited, recovery of the holotype, combined with more
recent biogeographic information, provides an opportunity to redescribe and provide additional morphological
characteristics for this species based on new measurements of the holotype. These additional morphological
characteristics take into account recent diagnostic features used to describe, identify, and separate other WNP
species (Walsh & Ebert, 2007; Walsh et al., 2011) and thus fills an informational gap for comparisons between S.
tergocellatoides and other WNP squatinids. An expanded key to the species of Indo-Western Pacific squatinids is
also provided since this region is an area of high biodiversity for squatinids, with the biogeography of several
species still remaining undefined.
Methods
Morphometric measurements modified after Compagno (2001) and following Walsh & Ebert (2007) and Walsh et
al. (2011) were taken to the nearest 0.1 mm, and are presented as a percentage of total length (TL) to facilitate
direct comparison with other regional squatinid species. It should be noted that the holotype TL measurement
presented in the original description by Chen (1963) is slightly larger (625 mm vs. 603 mm TL) to that of the TL
from the current measurements due to preservation; the holotype proportional measurements given here are based
on our new TL measurement. Vertebral counts were taken directly from digital radiographs, while tooth counts
were taken directly from the holotype. Pectoral and pelvic fin radial counts were also taken from the holotype.
Additional measurements of a male and female specimen were taken from Yano et al. (2005) for comparison to the
holotype. Photographs of S. tergocellatoides from other geographic regions throughout its range were obtained and
used to confirm its occurrence. Abbreviations for institutions and field numbers are as follows: Abbreviations for
institutions and field numbers are as follows: Australian National Fish Collection, Hobart, Australia (CSIRO);
British Museum of Natural History, London, United Kingdom (NHM); California Academy of Sciences, San
Francisco, California, U.S.A. (CAS); Hokkaido University, Laboratory of Marine Zoology, Faculty of Fisheries,
Hokkaido, Japan (HUMZ); National Taiwan University, Department of Zoology, Taipei, Taiwan (NTUM); David
A. Ebert field numbers (DAE). Tunghai University, Department of Biology, Taichung, Taiwan (THUP).
Institutional abbreviations follow Sabaj Pérez (2013).
Family Squatinidae Bonaparte, 1838
Genus Squatina Duméril, 1806
Squatina tergocellatoides Chen, 1963
(Figures 1–6, Table 1)
Common name. Ocellated angelshark.
Holotype. THUP 00348, 625 mm TL (original description), 603 mm TL (present study), immature female,
Taiwan Strait (Figure 1).
Diagnosis. A squatinid distinct from other WNP squatinids based on a combination of morphological
characteristics including dorsal surface with six distinct paired spots with lighter centers, nasal barbels and flaps
strongly fringed, and first dorsal fin originating posterior to pelvic fin free rear tips, a condition only found in S.
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SQUATINA TERGOCELLATOIDES REDESCRIPTION
japonicus; predorsal thorns on back absent on S. tergocellatoides, present on S. japonica; lateral head folds have
two rounded lobes on each side; upper lip arch semi-oval, upper lip arch height (1.1), upper lip arch width (4.1);
spiracles relatively large, length about 1.2 times eye diameter, 1.1 times eye-spiracle length, with smooth posterior
inner margins; pectoral fins acutely rounded at apices, with large prominent dark spots at anterior and posterior
angles; pelvic girdle width relatively short (21.5), about equal to head length (20.9); dorsal fins relatively small,
angular, prominent spots at base of each fin, interdorsal space (5.9–6.3) smaller than dorsal caudal space (7.5–7.8);
caudal fin lobed, ventral lobe triangular with its length greater than dorsal lobe length, upper postventral caudal
margin very long (6.1).
FIGURE 1. Dorsal view of Squatina tergocellatoides holotype, immature female, 625 mm TL (original description), 603 mm
TL (present study). Photograph by D. Ebert.
Description. Proportions as percentages of TL for the holotype and two other specimens from Yano et al.
(2005) are presented in Table 1.
TABLE 1 . Squatina tergocellatoides proportional measurements expressed as a percentage of total length (TL%) for the
holotype (THUP 00348) and two additional specimens taken from Yano et al. (2005) from Malaysia.
Holotype Yano et al. (2005)
THUP 00348 MSR 130 MSR 359
Female Male Female
Total Length (mm) 603 854 555
Pre-caudal length 85.6 87.2 80.7
Pre-orbital 2.9 2.8 3.2
Pre-spiracle length 7.3 7.4 7.5
Pre-gill length 16.2 12.9 15.9
Head Length 14.6
Pre-pectoral length 17.8 15.7 22.0
Pre-pelvic length 38.1 39.2 38.7
Snout-vent length 44.4 42.2 44.3
Pre-first dorsal fin length 63.3 66.2 61.8
Pre-second fin dorsal length 73.1 75.5 70.6
...... continued on the next page
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76 · Zootaxa 3752 (1) © 2013 Magnolia Press
TABLE 1. (Continued)
Holotype Yano et al. (2005)
THUP 00348 MSR 130 MSR 359
Female Male Female
Inter-dorsal fin length 6.3 6.2 5.9
Dorsal-caudal space 7.8 7.6 7.5
Pectoral-pelvic space 11.2 24.0 17.2
Vent-caudal length 37.8
Vent length 2.6
Mouth length 2.7 3.0 2.3
Mouth width 12.0 12.2 12.2
Upper labial furrow length 5.7
Lower labial furrow length 4.2
Internarial width 6.4 6.7 7.2
Nostril width 2.0
Anterior nasal flap length 1.8
Upper lip arch width 4.1
Upper lip arch height 1.1
Eye length 2.0 2.3 2.2
Eye height 1.7 1.5 1.7
Interorbital length 7.8 7.6 8.0
Spiracle length 2.4 2.3 2.5
Eye-spiracle length 2.1
Head height 5.7
Head width 20.9
Trunk height 6.6 6.1
Trunk width 18.6 15.2
Caudal peduncle height 2.5
Caudal peduncle width 4.6
Pectoral fin length 35.2
Pectoral fin anterior margin length 28.7 29.3 25.0
Pectoral fin base length 12.3 12.2 11.4
Pectoral fin height 16.9
Pectoral fin inner margin length 17.6 18.7 19.5
Pectoral fin posterior margin length 12.4 16.4 13.7
Pelvic fin length 24.4 24.0 23.3
Pelvic fin anterior margin 13.5 11.7 12.5
Pelvic fin base length 17.3 12.9 13.9
Pelvic fin height 14.1
Pelvic fin inner margin length 9.0 3.5 8.9
Pelvic fin posterior margin length 18.2
Pelvic girdle width 21.5
First dorsal fin length 6.5 6.3 5.9
First dorsal fin anterior margin length 7.0
First dorsal fin base length 3.5 3.9 3.4
...... continued on the next page
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SQUATINA TERGOCELLATOIDES REDESCRIPTION
Body greatly depressed and ray-like, width at pectoral insertions about 0.8 (0.9) times head length and 4.6
(5.5–5.7) in precaudal length. Head broad, depressed, width about 4.1 in precaudal length; head length to notch
about 5.9 times in precaudal length and 1.4 in head width; preorbital space flattened with slight median concave
depression, becoming strongly concave between eye orbitals; interorbital length 2.1 in preorbital length; lateral
head folds moderately expanded, with two to three rounded lobes on each side (Figures 2a, 2b).
Eyes small, oval, length and height diameters about equal; length about 3.9 (3.3–3.6) in interorbital length;
preorbital length greater than eye length. Spiracle inner margin smooth, width subequal to eye length; length
slightly greater than eye length; interspiracular length subequal to interorbital length; eye-spiracle length less than
eye length (Figure 2a).
FIGURE 2a. Dorsal view of head of Squatina tergocellatoides holotype. A small group of electrosensory pores lateral to the
spiracles are visible, as are a pair of large auditory pores located central and just posterior to the spiracles. Photograph by D. Ebert.
TABLE 1. (Continued)
Holotype Yano et al. (2005)
THUP 00348 MSR 130 MSR 359
Female Male Female
First dorsal fin height 5.6 6.3 4.1
First dorsal fin inner margin length 2.4
First dorsal fin posterior margin length 4.0 5.7 4.2
Second dorsal fin length 5.9 6.2 7.6
Second dorsal fin anterior margin length 6.7
Second dorsal fin base length 3.7 4.0 3.4
Second dorsal fin height 5.7 5.6 4.0
Second dorsal fin inner margin length 2.4
Second dorsal fin posterior margin length 4.0 5.0 4.0
Caudal fin upper lobe length 12.3 13.7 12.9
Caudal fin lower lobe length 14.9 15.3
Caudal lower postventral margin length 4.0
Caudal upper postventral margin length 6.1
Caudal subterminal fin margin length 3.4
THEISS & EBERT
78 · Zootaxa 3752 (1) © 2013 Magnolia Press
FIGURE 2b. Ventral view of head of Squatina tergocellatoides holotype. A group of electrosensory pores, located on the
lateral side of the head just medial and anterior to the pectoral fins, are visible. Photograph by D. Ebert.
Mouth wide, about 4.4 (4.1–5.3) times mouth length, slightly arched, with double folds in front of each angle
of lower jaw. Teeth awl-shaped, slightly curved and directed inwards; three functional series in each jaw; tooth
counts by row, upper 10–10, lower 10–10, totals 20 upper and lower, no medial teeth at symphysis. Labial furrows
extending medially from corners of mouth; upper labial furrow partially covered by dermal folds, slightly longer
than lower labial furrow. Exposed upper lip between bases of anterior nasal flaps forming a narrow high, semi-oval
arch; upper lip arch width 4.1, and height 1.1% of TL (Figure 3).
FIGURE 3. Anterior view of head of Squatina tergocellatoides holotype, depicting lip arch and fringed nasal barbels and flaps.
Photograph by D. Ebert.
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SQUATINA TERGOCELLATOIDES REDESCRIPTION
Nostrils terminal, separated from mouth by deep furrow, internarial width moderate 6.4 (6.7–7.2)% TL; nostril
width 3.2 in internarial width. Nasal flaps large, expanded at tips with moderately strong lobate fringes; flaps
extending from dermal folds above mouth; two distinct nasal barbels protruding from nasal flaps; posterior edges
of anterior nasal flaps strongly fringed, tips narrowly lobate and not strongly fringed; posterior nasal flaps low, not
greatly enlarged (Figure 4).
FIGURE 4. Photograph of nasal flap of Squatina tergocellatoides depicting strongly fringed edges. Photograph by W. White.
Dorsal surface covered with rough, tricuspidate denticles; snout, interorbital space, and anterior of spiracles
with clusters of small thornlets; mid-dorsal enlarged spines not present, outer margins of all fins smooth; ventral
surface smooth with some very fine close-set rough denticles on outer pectoral and pelvic fin anterior margins.
Ventral surface of tail covered with close-set imbricate denticles that do not extend to tail base.
Pectoral fins large, originating behind gills, moderately angular in shape, not forming a distinct anterior
shoulder; anterior margin mostly straight, extending to acutely rounded lateral apex, length 28.7 (25.0–29.3)% TL
and more than three quarters pectoral fin length; angle is more obtuse than right angle; posterior margin slightly
concave leading to acutely rounded free rear tip; inner margin convex, approximately half pectoral fin length.
Pectoral fin radial count 40.
Pelvic fins broadly triangular, originating anterior to pectoral fin free rear tip; anterior nearly straight, length
approximately 2.1 (2.0–2.5) times pectoral fin anterior margin length; base approximately 1.4 (1.1–1.2) times the
length of pectoral fin base. Pelvic girdle width between pelvic fin apices moderately broad, 21.5% TL, and about
1.5 times head length. Free rear fin tip tapering posteriorly to acute tip, ending just anterior to first dorsal fin origin;
inner margin slightly concave and short, about 2.7 (2.6–2.9) times pectoral fin length. Pelvic fin insertion furrows
on ventral surface extends in a narrow ellipse to anterior apogee of vent, vent is within ellipse. Pelvic fin radial
count 29.
Dorsal fins small and slightly angular, second dorsal similar in size or slightly smaller than first dorsal; origin
of first dorsal fin posterior to pelvic fin tips; interdorsal space is about 0.8 (0.8) of dorsal caudal space; dorsal fin
bases about equal in length; dorsal fin margins relatively straight, apices are lobed acutely rounded; posterior
THEISS & EBERT
80 · Zootaxa 3752 (1) © 2013 Magnolia Press
margin about 0.6 times length of anterior margin; inner margin approximately 3.5 times the length of anterior
margin; first dorsal fin base 1.8 in interdorsal space, and about 2.2 (1.9–2.2) in dorsal caudal space.
Caudal peduncle flattened dorsal-ventrally, with faintly defined longitudinal ridge along each side. Caudal fin
triangular in shape, posterior contour concave with lower lobe 1.2 (1.2–1.5) times length of upper lobe; subterminal
caudal fin margin slightly more than 0.5 length of upper postventral caudal margin; caudal lower postventral
margin slightly convex, approximately 0.7 length of caudal upper postventral margin (Figure 5).
Total vertebrae 137; total precaudal vertebrae 103; monospondylous vertebrae 48; diplospondylous vertebrae
to caudal origin 55; diplosondylous precaudal vertebrae to first dorsal fin origin 34.
FIGURE 5. Caudal fin of Squatina tergocellatoides holotype, triangular in shape with lower lobe longer than upper lobe.
Photograph by D. Ebert.
Colouration. In life, dorsal surface light yellowish brown covered with close-set, small, numerous rounded
white spots; fin borders whitish, except at fin bases that are blackish (Figure 6). The most striking feature of this
angel shark are the three pairs of prominent large black spots, each with a diameter greater than eye length; two on
each pectoral fin at anterior and posterior angle and one on each side near base of tail; another three pairs of lesser
defined, spots, one located at based of each dorsal fin and a third spot located laterally on tail about below first
dorsal fin. Ventral surface a uniform white to cream colour, margins of pectoral fins and tail similar in colour to
dorsal surface. After preservation, colouration fades to a uniform pale yellowish tan, with all major and minor spots
becoming indistinguishable. Dorsal and ventral fin borders become greyish after preservation.
Size. Maximum total length to at least 100 cm, with males maturing at about 85 cm TL and females at about
100 cm TL; size at birth is about 30 cm TL.
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SQUATINA TERGOCELLATOIDES REDESCRIPTION
FIGURE 6. Photographs of fresh specimens of Squatina tergocellatoides from Hong Kong (A), Vietnam (B) and Taiwan (C)
showing variation in colouration and spot patterns between individuals. Photographs by W. White (A) and H.-C. Ho (B & C).
THEISS & EBERT
82 · Zootaxa 3752 (1) © 2013 Magnolia Press
General Biology. Virtually nothing is known about the biology of this rather distinctive angelshark. It is an
inhabitant of outer continental shelves and upper slopes in warm temperate to tropical waters found at depths of
about 100 to 300 m. Litter size unknown. It may be caught as bycatch by trawlers and other fisheries operating in
the western Pacific, especially around Taiwan and possibly Indonesia, but there is no specific catch information on
the species. Qualitative observations by one of us (DAE) at fish markets in Taiwan indicate that demersal bony
fishes are a primary prey item of this species.
Distribution. Endemic to the western Pacific from the waters surrounding Taiwan in the north, southwards to
northwestern Malaysia, including the South China Sea, and the waters off Hong Kong and Vietnam (Compagno et
al., 2005; Yano et al., 2005; Walsh et al., 2011).
Discussion
The recovery of the holotype of S. tergocellatoides, previously thought to be lost, combined with additional
measurements and photographs of additional specimens, has enabled a more accurate comparison to other regional
squatinids based on current morphological measurements for this group of sharks (Walsh & Ebert, 2007). Squatina
tergocellatoides is similar to other regional squatinids but can be easily identified from other species by several
characters. For fresh specimens, colouration involving the three large spot pairs is unique to S. tergocellatoides and
is lacking for other known western North Pacific species; however, these prominent spot pairs fade after
preservation making these sharks indistinguishable from other regional squatinds based solely on colour.
Colouration in life varies slightly, and the condition and preservation of specimens appears to affect the visibility of
the spots. Specimens from Hong Kong (Figure 6a) and Vietnam (Figure 6b) were a darker and lighter brown,
respectively, and covered with small, round light brown spots, while a specimen from Taiwan was dark grey with
faded black spots and several small, distinct white spots (Figure 6c). The three major distinct pairs of black spots
remain constant although the less prominent pairs of spots, like those described from the holotype and in Yano et
al. (2005), are not always present. The Hong Kong and Vietnam specimens, both of which lack these
aforementioned spots, possess instead a pair of spots on each side of the tail, posterior to the larger spots at the base
of the tail.
A recent taxonomic review of WNP squatinids showed that the location of the pelvic fin tips in relation to the
first dorsal fin is a distinctive diagnostic feature (Walsh & Ebert, 2007). In S. tergocellatoides, the pelvic fin tips do
not reach the origin of the first dorsal fin, which is also the case for S. japonica. However, S. tergocellatoides can
be readily distinguished from S. japonica by colouration and the lack of mid-back thorns, the latter of which are
also missing from S. caillieti, S. formosa and S. nebulosa. The possession of fringed nasal barbels is another
defining characteristic of S. tergocellatoides and is not found in other WNP squatinids. Potential confusion exists
where Yano et al. (2005) comments that the barbels of this species are “weakly fringed” but then later states that
the “anterior nasal barbels [are] strongly fringed”. Photographs from Yano et al. (2005) and of recently obtained
specimens from Hong Kong and Taiwan, however, confirm that the nasal barbels are indeed strongly fringed as per
the original description of the holotype. Squatina tergocellatoides also differs from other WNP squatinids by
possessing the smallest interorbital length (7.8) and smallest mouth length (2.7). Although a lobed a caudal fin is
also present in S. caillieti, S. formosa and S. japonica, the caudal fin of S. tergocellatoides has a ventral lobe that is
triangular in shape and greater in length than the dorsal lobe.
The sensory electroreceptor pores on the holotype can be clearly seen on both the dorsal (Figure 2a) and
ventral (Figure 2b) sides, as can the pair of relatively large auditory pores located central and just posterior to the
spiracles (Figure 2a). The low number of ventral pores is comparable to species from the family Orectolobidae,
which share a similar dorso-ventrally compressed body morphology to squatinids, and is likely related to the
ambush predatory strategy that members of both families employ (Theiss et al., 2011). The concurrent low number
of dorsal pores, however, is not typically seen and may suggest that the electrosensory system may not be of
relative importance to these species, compared to other sensory systems such as vision (Fouts & Nelson, 1999).
The number and distribution of electrosensory pores is consistent among species of the same family, so it is
therefore highly likely that other squatinids share a similar electroreceptor pattern to S. tergocellatoides (Kempster
et al., 2012).
Four geographically sympatric species of squatinids are known to occur in Taiwanese waters, making it a
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SQUATINA TERGOCELLATOIDES REDESCRIPTION
hotspot of biodiversity for this genus. The range of two species, S. japonica and S. nebulosa, appear to occur in
more northerly waters extending to Japan and Korea, while the geographic range of S. formosa is poorly known
and unconfirmed from outside Taiwanese waters at this time. Based on recent records, S. tergocellatoides appears
to be a more southerly occurring species having been recorded farther south to off Hong Kong, Vietnam, and
Malaysia (Yano et al., 2005; Walsh et al., 2011). The only other known species of WNP squatinid, S. caillieti, was
caught off Luzon in the Philippine Islands and it is likely that the distribution of this species may overlap the
southern distribution of S. tergocellatoides, but there are no confirmed records of it from outside the Philippines
(Walsh et al., 2011). Conversely there are no confirmed records of S. tergocellatoides from the Philippines.
However, it is likely that S. tergocellatoides overlaps in its southern distribution with the tropical S. legnota, which
has been recorded in Indonesian waters close to Malaysia (Last & White, 2008). This species can be readily
distinguished from S. tergocellatoides using colouration and position of pelvic fin free rear tips in relation to dorsal
fin origin. More specimens of S. tergocellatoides, as well as S. caillieti and S. legnota, are required to confirm
suspected distributional localities and ranges.
The IUCN Red List of Threatened Species lists S. tergocellatoides as vulnerable mainly due to intense bottom
trawl fisheries that occur within its known range (Walsh & Ebert, 2009). This species does not appear to be
abundant anywhere, but it is taken in small numbers around Taiwan and elsewhere, including Vietnam, Hong
Kong, and Malaysia. Improved species-specific identification of this species and other regional squatinids species
will help in the conservation and management of these sharks.
Key to Indo-Western Pacific species of Squatina
1a. Nasal barbels strongly fringed and with multiple branches or fine cirri. Posterior edges of anterior nasal flaps between nasal
barbels and tips strongly fringed and multi-branched or finely cirrate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.
1b. Nasal barbels simple or bifurcated. Posterior edges of anterior nasal flaps smooth to moderately fringed . . . Squatina legnota.
2a. Paired ocelli present on back, tail and pectoral fins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.
2b. No ocelli on dorsal surface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.
3a. Nasal barbels and anterior nasal flaps greatly expanded and deeply fringed. Lateral head folds low and without rounded lobes.
Three pairs of large ocelli with centers resembling mitotic figures on back near bases of pectoral and pelvic fins. . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Squatina tergocellata.
3b. Nasal barbels and anterior nasal flaps moderately expanded and finely fringed. Lateral head folds higher and with a pair of low
rounded lobes on each side. Six pairs of smaller, light-centered ocelli on back, pectoral and pelvic fins, and tail. . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Squatina tergocellatoides.
4a. Interorbital space flat or convex. No orbital thorns. Lower caudal lobe with numerous dark spots. . . . . . . . Squatina australis.
4b. Interorbital space concave. Orbital thorns normally present. Lower caudal lobe with more pale spots than dark spots. . . . . . 5.
5a. Nasal barbels strongly bifurcate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.
5b. Nasal barbels weakly or not bifurcate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.
6a. Upper surface mainly covered with small white, dark-edged spots. Predorsal thorns absent from midline of back. . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Squatina albipunctata.
6b. Upper surface mainly covered in bluish spots; a single white spot on nuchal region. A row of small predorsal thorns on back,
mostly single . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Squatina pseudocellata.
7a. Lateral head folds with two lobes at and in front of mouth corners on each side. . . . . . . . . . . . . . . . . . . . . Squatina nebulosa.
7b. Lateral head folds with a single lobe on each side or none. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.
8a. Angle of pectoral apex broadly obtuse, much greater than a right angle. Nasal barbels highly depressed and membranous.. . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Squatina formosa.
8b. Angle of pectoral apex narrowly obtuse, usually slightly greater than a right angle. Nasal barbels thickened and subcylindrical.
9a. No enlarged predorsal thorns on back, at most weakly enlarged denticles. . . . . . . . . . . . . . . . . . . . . . . . . . . Squatina africana.
9b. A row of enlarged predorsal thorns on back. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Squatina japonica.
Material examined
Squatina caillieti: Holotype: CAS 226473, immature female, 328 mm total length, Taiwan Fisheries Research
Institute Fishery Researcher 1 sta. FR1-PHI-02-95, 23 September 1995, 363-385 m, Philippines, Luzon, 13°08.98–
09.84'N, 124°04.72–00.01'E, collected by L.J.V. Compagno and P.R. Last.
Squatina formosa: (4 specimens) Holotype: NTT7213130 (now labelled as NTUM 01329), immature female,
Dong-gang, Pingtung, Taiwan, 31 January 1972; DAE 881805, immature male, Da-xi, Taiwan, May 1988,
THEISS & EBERT
84 · Zootaxa 3752 (1) © 2013 Magnolia Press
collected by David A. Ebert; DAE 052105, immature male, Da-xi, Taiwan, May 2005, collected by David A.
Ebert; DAE 052305-2, immature female, Da-xi, Taiwan, May 2005, collected by David A. Ebert.
Squatina japonica: (4 specimens) HUMZ 107395, immature female, off Shirahama, Shimoda City, Shizuoka
prefecture, Japan, 27 January 1986, caught with a bottom gill net at 30 m; HUMZ 105913 immature male, off
Itado, Shimoda, Shizuoka prefecture, Japan, 19 Nov 1985, caught with a bottom gill net at 10m; CAS 20955:
immature male, Japan, Tokyo market, collected by R/V Snyder and Sindo as part of the “Albatross 1906 cruise”;
CAS 20956, immature male, Japan, Tokyo market, collected by R/V Snyder and Sindo as part of the “Albatross
1906 cruise.”
Squatina legnota: (1 specimen) Paratype: CSIRO H 6565-01, adult male, 1252 mm TL, Tanjung Luar fish
landing site, Lombok, Indonesia, 08o 45’S, 116o 35’ E, 9 September 2004.
Squatina nebulosa: (8 specimens) Holotype: BMNH 1862.11.1.89, immature female, Japan; Paratypes of S.
formosa, three specimens, were examined and reidentified as S. nebulosa by Walsh & Ebert (2007). These
specimens are NTU7222433 (now labelled as NTUM 01327), and NTU7041632 (now labelled as NTUM 01328),
immature female, Tashi, Taiwan (24o 56.5’N, 121o 53.0’E) in single trawling net at 100-120 fathoms, 16 April
1970, collected by W.H. Ting; NTU7041632 (now labelled as NTUM 01328), immature female, Tashi, Taiwan, 24
February 1972, collected by W.H. Ting; DAE 882105, immature female, Tashi, Taiwan, May 1988, collected by
David A. Ebert; DAE 052305-1, immature male, Tashi, Taiwan, May 2005, collected by David A. Ebert; DAE
052505, immature male, May 2005, collected by David A. Ebert; HUMZ 149422, immature female, caught in
trawl net in Okinawa Trough, 25° 37.28’N, 126° 05.35’E to 25° 38.12’N, 126° 07.83’E, 2 August 1994; HUMZ
149423, immature male, caught in trawl net in Okinawa Trough, 25° 37.28’N, 126° 05.35’E to 25° 38.12’N, 126°
07.83’E, Japan, 2 August 1994.
Acknowledgements
We thank H.-C. Ho (NMMBA) who found the previously missing holotype, K.-T. Shao (ASIZP), S.-J. Joung
(NTOU), W. White, P. Last, A. Graham, (CSIRO), G. Burgess (UF) and W. Smith (Oregon State University) for aid
in obtaining comparative squatinid specimens used for this project, K. Nakaya (Hokkaido University) for his
generous assistance in loaning S. nebulosa specimens, D. Catania, J. Fong, T. Iwamoto and M. Hoang (CAS) for
help with S. japonica specimens and references on squatinds. Support for this project was provided by NOAA/
NMFS to the National Shark Research Consortium and the David and Lucile Packard Foundation to the Pacific
Shark Research Center. Additional support provided by a National Science Foundation grant "Jaws and Backbone:
Chondrichthyan Phylogeny and a Spine for the Vertebrate Tree of Life" DEB-01132229 to G. Naylor, College of
Charleston, and the National Science Council, Taiwan and National Museum of Marine Biology and Aquarium
(NMMBA 102200255), Taiwan supported a chondrichthyan biodiversity workshop in Taiwan in March 2012 that
allowed examination material from this region.
References
Bleeker, P. (1858) Vierde bijdrage tot de kennis der icthyologische fauna van Japan. Acta Societatis Scientiarum Indo-
Neerlandicae, 3, 1–46.
Bonaparte, C.L. (1838) Iconografia della fauna italica per le quattro classi degli animali vertebrati. Tomo III. Pesci. Roma.
Iconografia. Vol. 3. Fasc. 22–23, puntata 104, 110–120, 2 pls.
Chen, J.T.F. (1963) A review of the sharks of Taiwan. Biology Bulletin of Tunghai University Ichthyology Series, 1, 1–102.
Compagno, L.J.V. (1973) Interrelationships of living elasmobranchs. Interrelationships of fishes. Zoological Journal of the
Linnean Society, Supplement 1, 53, 15–61.
Compagno, L.J.V. (1977) Phyletic relationships of living sharks and rays. American Zoologist, 17, 303–322.
http://dx.doi.org/10.1093/icb/17.2.303
Compagno, L.J.V. (2001) Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Vol. 2.
Bullhead, mackerel, and carpet sharks (Heterodontiformes, Lamniformes, and Orectolobiformes). FAO Species Catalogue
for Fishery Purposes. No. 1, vol.2. Rome, FAO. 2001. 269 pp.
Zootaxa 3752 (1) © 2013 Magnolia Press · 85
SQUATINA TERGOCELLATOIDES REDESCRIPTION
Compagno, L.J.V., Dando, M. & Fowler, S. (2005) A field guide to the sharks of the world. Harper Collins Publishing Ltd.,
London, 368 pp.
de Carvalho, M.R. (1996) Higher-level elasmobranch phylogeny, basal squaleans, and paraphyly. In: Stiassny, M.L.J., Parenti,
L.R. & Johnson, G.D. (Eds.), Interrelationships of Fishes. Academic Press, San Diego, London, pp. 35–62.
Duméril, A.M.C. (1806) Zoologie Analytique: ou méthode naturelle de classificatio des animaux. Allais, Paris, 377 pp.
Ebert, D.A., Fowler, S. & Compagno, L.J.V. (2013) Sharks of the world: a fully illustrated guide to the sharks of the world.
Wild Nature Press, Plymouth, 528 pp.
Ebert, D.A. & Winton, M.V. (2010) Chondrichthyans of high latitude seas. In: Carrier, J.C., Musick, J.A. & Heithaus, M.R.
(Eds.), The biology of sharks and their relatives, volume 2. CRC Press, Boca Raton, pp. 115–158.
Fouts, W.R. & Nelson, D.R. (1999) Prey capture by the Pacific angel shark, Squatina californica: visually mediated strikes and
ambush-site characteristics. Copeia, 1999 (2), 304–312.
http://dx.doi.org/10.2307/1447476
Kempster, R.M., McCarthy, I.D. & Collin, S.P. (2012) Phylogenetic and ecological factors influencing the number and
distribution of electroreceptors in elasmobranchs. Journal of Fish Biology, 80, 2055–2088.
http://dx.doi.org/10.1111/j.1095-8649.2011.03214.x
Last, P.R. & Stevens, J.D. (2009) Sharks and rays of Australia. CSIRO, Melbourne, 644 pp.
Last, P.R. & White, W.T. (2008) Three new angel sharks (Chondrichthyes: Squatinidae) from the Indo-Australian region.
Zootaxa, 1743, 1–26.
Naylor, G.J.P., Caira, J.N., Jensen, K., Rosana, K.A.M., White, W.T. & Last, P.R. (2012a) A DNA sequence-based approach to
the identification of shark and ray species and its implications for global elasmobranch diversity and parasitology. Bulletin
of the American Natural History Museum, 367, 1–263.
http://dx.doi.org/10.1206/754.1
Naylor, G.J.P., Caira, J.N., Jensen, K., Kerri, Rosana, K.A.M., Straube, N. & Lakner, C. (2012b) Elasmobranch phylogeny: a
mitochondrial estimate based on 595 species. In: Carrier, J.C., Musick, J.A. & Heithaus, M.R. (Eds.), Biology of sharks
and their relatives, second ed. CRC Press, Boca Raton, pp. 31–56.
Naylor, G.J.P., Ryburn, J.A., Fedrigo, O. & Lopez, A. (2005) Phylogenetic relationships among the major lineages of modern
elasmobranchs. In: Hamlett, W.C. (Ed.), Reproductive biology and phylogeny of Chondrichthyes–sharks, batoids and
chimaeras. Science Publisher, Inc., Enfield, pp. 1–25.
Regan, C.T. (1906) Descriptions of some new sharks in the British Museum Collection. Annals and Magazine of Natural
History (Series 7), 18, 435–440.
http://dx.doi.org/10.1080/00222930608562643
Sabaj Pérez, M.H. (Ed.) (2013) Standard symbolic codes for institutional resource collections in herpetology and ichthyology:
an Online Reference. Version 4.0. American Society of Ichthyologists and Herpetologists, Washington, DC. Available
from: http://www.asih.org/ (accessed 28 June 2013)
Shen, S.-C. & Ting, W-H. (1972) Ecological and morphological study on fish fauna from the waters around Taiwan and its
adjacent islands. Notes on some continental shelf fishes and descriptions of two new species. Bulletin of the Institute of
Zoologic Academy, Sinica, 11, 13–31.
Shirai, S. (1996) Phylogenetic interrelationships of neoselachians (Chondrichthyes: Euselachii). In: Stiassny, M.L.J., Parenti,
L.R. & Johnson, G.D. (Eds.), Interrelationships of Fishes. Academic Press, San Diego, pp. 9–34.
Theiss, S.M., Collin, S.P. & Hart, N.S. (2011) Morphology and distribution of the ampullary electroreceptors in wobbegong
sharks: implications for feeding behaviour. Marine Biology, 158, 723–735.
http://dx.doi.org/10.1007/s00227-010-1595-1
Vaz, D.F.B. & de Carvalho, M.R. (2013) Morphological and taxonomic revision of species of Squatina from the southwestern
Atlantic Ocean (Chondrichthyes: Squatiniformes: Squatinidae). Zootaxa, 3695(1), 1–81.
http://dx.doi.org/10.11646/zootaxa.3695.1.1
Walsh, J.H. & Ebert, D.A. (2007) A review of the systematics of western North Pacific angel sharks, genus Squatina, with
redescriptions of Squatina formosa, S. japonica, and S. nebulosa (Chondrichthyes: Squatiniformes, Squatinidae). Zootaxa,
1551, 31–47.
Walsh, J.H. & Ebert, D.A. (2009) Squatina tergocellatoides. In: IUCN 2013. IUCN Red List of Threatened Species. Version
2013.1. Available from: http://www.iucnredlist.org (accessed 20 October 2013)
Walsh, J.H., Ebert, D.A. & Compagno, L.J.V. (2011) Squatina caillieti sp. nov., a new species of angel shark
(Chondrichthyes:Squatiniformes: Squatinidae) from the Philippine Islands. Zootaxa, 2759, 49–59.
White, W.T. & Sommerville, E. (2010) Elasmobranchs of tropical marine ecosystems. In: Carrier, J.C., Musick, J.A. &
Heithaus, M.R. (Eds.), Sharks and their relatives II. CRC Press, Boca Raton, pp. 159–240.
Yano, K., Ali, A., Gambang, A.C., Hamid, I.A., Razak, S.A. & Zainal, A. (2005) Sharks and Rays of Malaysia and Brunei
Darussalam. Marine Fishery Resources Development and Managment Department, Southeast Asian Fisheries
Development Center, Kuala Terengganu, Malaysia, 591 pp.
