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A New Mesophotic Clingfish (Teleostei: Gobiesocidae) from the Bahamas


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A new species of clingfish belonging to the genus Derilissus is described from a deep coral wall in the Exumas, Bahamas. The new species is distinguished from congeners by a unique pigmentation pattern and coloration, the presence of 47 total pectoral-fin rays, a strongly convex posterior margin on disk region B, and by a unique arrangement of papillae on disk region C. The new species is characterized by bright orangish-red coloration on the flank, a yellow head, and a prominent black oval marking on the caudal peduncle. Like other members of the genus, the new species appears to be restricted to the mesophotic zone, and was collected at 286 fsw.
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A New Mesophotic Clingfish (Teleostei: Gobiesocidae) from the Bahamas
John S. Sparks
and David F. Gruber
A new species of clingfish belonging to the genus Derilissus is described from a deep coral wall in the Exumas, Bahamas.
The new species is distinguished from congeners by a unique pigmentation pattern and coloration, the presence of 47
total pectoral-fin rays, a strongly convex posterior margin on disk region B, and by a unique arrangement of papillae on
disk region C. The new species is characterized by bright orangish-red coloration on the flank, a yellow head, and a
prominent black oval marking on the caudal peduncle. Like other members of the genus, the new species appears to be
restricted to the mesophotic zone, and was collected at 286 fsw.
WHILE conducting a series of deep research dives
in the Exumas, Bahamas, a diminutive and
brightly colored clingfish (Gobiesocidae) was
collected using rotenone on a wall dive at roughly 300 fsw.
Based on small adult size, fusion of the gill membranes to
the isthmus, and morphology of the sucking disk, it was
immediately clear that the specimen represented a new
species of the diminutive deepwater genus Derilissus Briggs,
Derilissus currently comprises four species, D. nanus Briggs,
1969, D. vittager Fraser, 1970, D. kremnobates Fraser, 1970,
and D. altifrons Smith-Vaniz, 1971, and was described by
Briggs (1969) to encompass a diminutive new species of
clingfish collected in relatively deep waters of the Bahamas
that differed from all other New World gobiesocids in
having the gill membranes fused to the isthmus. Soon
thereafter, three additional species of Derilissus were de-
scribed (Fraser, 1970; Smith-Vaniz, 1971), all from deeper
waters of the Western Atlantic.
Herein, we formally describe a new species of Derilissus
from a deep coral wall in the Exumas, Bahamas, western
Atlantic Ocean. Further, we discuss the apomorphic mor-
phological features that distinguish the new species from
congeners and other Bahamian gobiesocids.
The holotype was collected using closed-circuit Trimix
rebreather SCUBA systems at a small rotenone station in
280–300 fsw on Bock Wall (23u49955.20N, 276u9910.440W),
near Lee Stocking Island, Exumas, Bahamas. The site is
characterized by a fringing barrier reef beginning at 70 fsw,
and dropping vertically to over 2000 fsw. The vertical ‘wall’
is comprised of a series of ledges and undercuts in roughly
30- to 50-foot intervals. A distinct overhanging ledge that
created a notch from 280 to 300 fsw was identified as a
target collection area. Rotenone was dispersed over this area,
and after 15 to 20 minutes affected specimens were located
with a compact light-emitting diode dive light, collected
using a small hand net, and individually bagged for
transport back to the surface. The specimens were immedi-
ately placed on ice to preserve coloration and photographed.
The holotype of the new species, the only individual that
could be collected, was one of a group of four or five of the
same species living in very near proximity to a small coral
Osteological features of the new species and comparative
gobiesocid taxa were analyzed using radiographs, high-
resolution digital images, and via the examination of whole
specimens under a dissecting scope. Point-to-point morpho-
metric measurements were recorded to the nearest 0.1 mm
using dial calipers. Measurements follow Briggs (1955),
unless noted otherwise. Standard length (SL) is used
throughout. Vertebral count excludes the ural centrum
(5last half-centrum). Following Smith-Vaniz (1971), princi-
pal caudal rays are defined here as those attached to or
articulating with the hypurals, and are presented in the
formula ventral +dorsal. Disk width is measured at the
widest point of the pelvic disk. Institutional abbreviations
are as listed in Leviton et al. (1985) and Sabaj Pe´rez (2010).
Derilissus lombardii, new species
Figures 1, 2; Table 1
Holotype.—AMNH 251906, 10.9 mm SL, Exumas, Bahamas,
Bock Wall, 23u49955.20N, 276u9910.440W, 286 fsw near a
small coral head using Tri-mix mixed-gas closed-circuit
rebreather SCUBA systems, M. Lombardi, J. Godfrey, D. F.
Gruber, and J. S. Sparks, 4 May 2011.
Diagnosis.—AmemberofDerilissus distinguished from
congeners (and all other Bahamian gobiesocids) by the
presence of bright orangish-red coloration, a yellow head,
and a prominent black oval patch on the caudal peduncle.
The new species is further distinguished from congeners by
the pattern of papillae in disk region C (Fig. 2). Anteriorly,
two distinct medial clusters, each comprising 8–9 closely
arrayed papillae plus a single papilla anterior of each cluster,
are present (vs. 2–5 papillae in each central cluster and 4–5
papillae arranged in a distinct crescent posterolaterally in
congeners). Posteriorly, papillae in disk region C are
arranged in a crescent with a single additional papilla dorsal
to its midpoint (vs. papillae arranged in an inverted V-
shaped pattern in D. nanus,D. altifrons, and D. kremnobates,
or clumped in D. vittager). Uniquely among members of
Derilissus, the posterior margin of disk region B in the new
species is strongly convex (vs. straight to weakly convex in
congeners) with the rows of papillae arranged serially in a
semi-circular pattern forming concentric crescents (vs. rows
more or less straight). Lastly, the new species is unique
American Museum of Natural History, Department of Ichthyology, Division of Vertebrate Zoology, Central Park West at 79
Street, New
York, New York 10024; E-mail: Send reprint requests to this address.
City University of New York, Baruch College, Department of Natural Sciences, 17 Lexington Avenue, New York, New York 10010; E-mail:
Submitted: 8 September 2011. Accepted: 12 January 2012. Associate Editor: D. Buth.
F2012 by the American Society of Ichthyologists and Herpetologists DOI: 10.1643/CI-11-124
Copeia 2012, No. 2, 251–256
among congeners in possessing a total of 47 pectoral-fin
Description.—Selected proportional measurements and me-
ristic data presented in Table 1. Comparatively, a very small
gobiesocid. Body moderately wide and rounded anteriorly,
becoming progressively laterally compressed posteriorly.
Caudal peduncle strongly laterally compressed. Head deep
and profile of snout strongly convex, not dorsoventrally
compressed, forming angle of about 75uin lateral view.
Mouth small and rostroventrally oriented. Margin of lower
jaw wider laterally, with moderate medial constriction at
symphysis in ventral view. Eye large, with distinctive
spotted ring. Anterior nostril tubular and elongate, without
dermal flap. Posterior nostril tubular and short. Pore system
on head well developed and as described by Fraser (1970:fig.
2) and Smith-Vaniz (1971) for other members of genus. Pore
system lacking on flank. Body asquamate.
Fig. 1. Derilissus lombardii, new species, holotype, AMNH 251906, 10.9 mm SL, Exumas, Bahamas. Images taken immediately following capture
illustrate live coloration. (A) Lateral view. (B) Dorsal view. (C) Ventral view.
252 Copeia 2012, No. 2
Upper jaw with two distinct rows of crowded, relatively
strongly tricuspid and bicuspid teeth anteriorly, grading to a
single row of weakly bicuspid and unicuspid teeth laterally and
posteriorly. Teeth in a single row in lower jaw, and procumb-
ently implanted. Lower jaw dentition strongly tricuspid
medially, becoming bicuspid laterally, and unicuspid posteri-
orly. Teeth more closely arrayed anteriorly, and becoming more
sparsely arranged posteriorlyinbothupperandlowerjaw.
Fin-ray counts as follows: dorsal 8; anal 7; pectoral 24 (left)
+23 (right) 547 total; pelvic I,4; and principal caudal rays
7+6 (procurrent rays could not be observed in radiographs).
Gill membrane attached to isthmus, and with fleshy,
dorsocaudally directed prong at about midpoint of opening.
Upper attachment of gill membrane is opposite approxi-
mately 9
pectoral-fin ray, and lower attachment is opposite
approximately 21
or 22
pectoral ray. Membrane from last
pelvic ray loosely attached to approximately 20
or 21
pectoral ray. Vertebral count 25.
Four gill arches present on each side, with feeble fourth
arch closely aligned with lower pharyngeal bone. Gill arches
1–3 bear large, complex, brush-like filaments (which
strongly resemble the sea pen, Pennatula), whereas none
are present on fourth arch. Thin, relatively short and
triangular gill rakers present on all four arches. Five
branchiostegal rays present on each side, and arranged in
two distinct groups (1+4). Arrangement and articulation of
branchiostegals as described by Smith-Vaniz (1971:292).
Disk large, well developed, and single. Papillae numerous
and distributed in unique pattern. Arrangement of papillae in
disk region C appears to be phylogenetically informative
within Derilissus as observed by Smith-Vaniz (1971). As
shown in Figure 3, in D. nanus,D. kremnobates, and D.
altifrons papillae on posterior portion of disk region C
arranged in inverted V-shaped pattern (Smith-Vaniz,
1971:fig. 3a–c), whereas in D. vittager, papillae in region
more or less clumped (Smith-Vaniz, 1971:fig. 3d). In contrast,
in D. lombardii, new species, papillae on posterior portion of
disk region C form a crescent with single additional papilla
dorsal to its midpoint (Figs. 1C, 2). Anteriorly in D. lombardii,
two distinct circular medial clusters, each comprising 8–9
closely arrayed papillae plus a single papilla anterior of each
cluster, present (vs. 2–5 papillae in each central cluster and 4–
5 papillae arranged in a separate and distinct crescent
posterolaterally in congeners; Fig. 3). Posterior margin of
disk region B strongly convex with rows of papillae in region
serially arranged in semi-circular pattern forming concentric
crescents (Figs. 1C, 2).
Coloration and pigmentation pattern in life.—Photographed
while fresh and coloration in life represented in Figure 1.
Overall, body bright yellow to orangish-red. Flank bright
orangish-red along midline and ventrally. Yellow to light
orange above midline. Faint orange vertical bars visible on
flank, particularly dorsally. Jaws, snout, and head bright
yellow. Throat light grayish-white to pale yellow. Dorsal
aspect of body mostly bright orange from about mid-orbit to
origin of dorsal fin. Distinctive orange spotting in interor-
bital region and extending slightly posterior to nape. Dark
orangish-red patch posterior to orbit. Black eye ring with
golden and orangish speckling. Distinctive black oval
marking on caudal peduncle. Pelvic disk hyaline to pale
yellow, and peppered with numerous bright orange papillae.
Pectoral fin bright yellow. Dorsal, anal, and caudal fin
hyaline with reddish spotting, particularly distally.
Coloration and pigmentation pattern in alcohol.—Similar to
that described above for coloration in life, except that
Table 1. Morphometric and Meristic Data for Holotype of
Derilissus lombardii.
Standard length (mm) 10.9
Percentage of SL
Head length 38.5
Head width 30.3
Body depth 24.8
Snout length 12.8
Eye length 11.9
Interorbital width (IOW) 10.1
Pelvic disk length 35.8
Pelvic disk width 25.7
Caudal peduncle depth (CPD) 11.0
Caudal peduncle length (CPL) 7.3
Percentage of HL
Snout length 33.3
Eye length 31.0
Interorbital width (IOW) 26.2
Eye length %IOW 118.2
CPD %CPL 150.0
Dorsal fin 8
Anal fin 7
Pectoral fin 24(L) +23(R)
Pelvic fin I, 4
Principal caudal rays 7 +6
Vertebrae 25
Fig. 2. Schematic of sucking disk of holotype of Derilissus lombardii,
AMNH 251906, showing distribution of papillae. Papillae in disk region
C are indicated by solid black circles.
Sparks and Gruber—New mesophotic clingfish from the Bahamas 253
Fig. 3. Ventral view illustrating pattern of papillae on disk in: (A) Derilissus kremnobates, holotype, ANSP 109625; (B) D. altifrons, holotype, ANSP
112690; (C) D. vittiger, holotype, ANSP 109626; (D) D. nanus, holotype, UF 15932.
254 Copeia 2012, No. 2
yellow, orange, and reddish coloration fades significantly in
ethanol. Prominent black oval blotch on caudal peduncle
still detectable in preservation.
Habitat and distribution.—Although described from a single
specimen collected on a deep, mesophotic reef near Lee
Stocking Island in the Exumas, Bahamas, the holotype was
one of a group of four or five individuals living proximate to
a small coral head on an outcrop above an undercut and
ledge in 286 fsw (Fig. 4); however, these additional speci-
mens could not be collected. Additional images of the
habitat of the new species can be observed on the
Mesophotic Coral Ecosystems website (www.mesophotic.
org/index.php?page5photos&photographerid5272). Given
that deep mesophotic reefs have only recently become
accessible via technical SCUBA, it is impossible at this time
to speculate on the geographic range of the new species.
Etymology.—Named after the collector of holotype, Michael
Lombardi, who was part of the deep diving team, along with
Jeff Godfrey, on our Bahamas expedition. Specific epithet,
lombardii, to be treated as a noun in apposition.
Remarks and comparisons.—Although it may seem somewhat
surprising to find a new clingfish in the Bahamas, particu-
larly near Lee Stocking Island, given the significant amount
of ichthyological survey work that has taken place in the
region (e.g., Bo¨hlke, and Chaplin, 1968, 1993; Smith-Vaniz
and Bo¨hlke, 1991), small reclusive fishes on deep mesopho-
tic reefs are difficult to access and observe, and even more
difficult to collect. Due to their frequent cryptic coloration,
small size, and elusive behavior, gobiesocids are frequently
overlooked and remain undetected even in easily accessible
habitats, such as shallow intertidal regions (Craig and
Randall, 2009). It is, therefore, not surprising that new
species of deep water, reef-associated fishes continue to be
discovered in regions that have otherwise been subjected to
a significant amount of ichthyological survey work, given
that mesophotic communities, light-dependent coral com-
munities occurring in the lower reaches of the photic zone,
have only recently become accessible via technical diving
The new species seems to be closely associated with deep
reefs, not straying far from the safety of a coral head. Other
species of Derilissus have been captured in trawls, suggesting
that they are more open water benthic taxa. All species in
the genus are known only from relatively deep water (45–
266 m; 148–873 fsw) compared to other gobiesocids.
In addition to apomorphic features of the pelvic disk
discussed in detail above and the number of pectoral-fin
rays, the new species is readily distinguished from congeners
based on its vivid orangish-red coloration, yellow head, and
prominent black oval marking on the caudal peduncle. Both
D. kremnobates and D. vittager are characterized by chain-like
patterns on the flank (vs. broad vertical bars and spotting in
D. lombardii), and radiating streaks around the orbit in D.
kremnobates, or dark lines on the head in D. vittager (vs. solid
coloration or faint spotting in D. lombardii). Deilissus nanus
Fig. 4. Deep reef habitat on Bock Wall, Exumas, Bahamas. The holotype of the new species was collected from the outcrop near the top of the image
(image taken at approximately 300 fsw). Image by Michael Lombardi.
Sparks and Gruber—New mesophotic clingfish from the Bahamas 255
is reportedly black on the sides, grading to brownish above
(Briggs, 1969). Derilissus kremnobates has two pale spots on
the caudal membrane (Fraser, 1970:fig. 4), whereas D.
vittager possesses dark blotches anteriorly on both the dorsal
and anal membranes (Fraser, 1970:fig. 5). In contrast, these
regions are hyaline in D. lombardii. The new species is
unique in possessing a large black oval marking midlaterally
on the caudal peduncle.
Although coloration in life is unknown for D. altifrons,
some faint, diffuse pigmentation can be seen in the caudal
region of the holotype (ANSP 112690), particularly dorsally
(also see Smith-Vaniz, 1971:fig. 1). After several months in
ethanol the black caudal marking in D. lombardii, new
species, is still visible, although much of the remaining
pigmentation in this specimen has faded. Given the
persistence of the caudal marking in the new species in
preservation and the distribution of what little pigment
remains in the holotype of D. altifrons, it seems likely that D.
altifrons did not possess a large, prominent black midlateral
marking spanning the length of the caudal peduncle in life
(Fig. 1). Regardless, the new species is readily distinguished
from D. altifrons by a number of features already discussed,
including a lower pectoral ray count (47 vs. 52 in D.
altifrons), two distinct rows of teeth in the upper jaw (vs.
single row in D. altifrons), and tricuspid teeth in both upper
and lower jaws (vs. bicuspid in D. altifrons).
Gobiesocids used in comparative analyses arranged alpha-
betically, with additional relevant information presented for
other members of Derilissus.
Acyrtops beryllinus: AMNH 34410, 6 ex., Bahamas; AMNH
87230, 1 ex., Florida; AMNH 225258, 1 ex., Bahamas.
Acyrtus artius: AMNH 18568, 3 ex., Bahamas; AMNH 30005,
1 ex., Bahamas; AMNH 31186, 2 ex., Bahamas.
Acyrtus rubiginosus: AMNH 23998, 32 ex., Bahamas; AMNH
24990, 54 ex., Bahamas; AMNH 34248, 69 ex., Bahamas; AMNH
249672, 2 ex., Bahamas; AMNH 250336, 1 ex., Bahamas.
Arcos macrophthalmus: AMNH 239026, 2 ex., Bahamas;
AMNH 249673, 1 ex., Bahamas.
Derilissus altifrons: ANSP 112690, holotype, 17.1 mm SL,
Dominica Channel, western Atlantic, 15u13.09N, 60u56.99W,
depth 68–69 m.
Derilissus kremnobates: ANSP 109625, holotype, 27.6 mm SL,
Arrowsmith Bank, Caribbean Sea, 21u059N, 86u239W, depth
80–145 fm.
Derilissus nanus: UF 15932, holotype, 13.5 mm SL, off West
Plana Cay, Bahamas, depth 48–51 m.
Derilissus vittiger: ANSP 109626, 18.6 mm SL, Venezuela,
11u01.89–11u01.09N, 65u34.29–65u36.39W, depth 37 fm.
Gobiesox lucayanus: AMNH 21270, 2 ex., Bahamas.
Gobiesox punctulatus: AMNH 19962, 1 ex., Bahamas; AMNH
28970, 1 ex., Bahamas; AMNH 30939, 1 ex., Antigua; AMNH
33232, 1 ex., Bahamas.
Tomicodon cryptus: AMNH 237341, 1 ex., Venezuela; AMNH
238924, 1 ex., Curacao.
Tomicodon fasciatus: AMNH 249671, 4 ex., Bahamas; AMNH
249710, 1 ex., Bahamas.
Tomicodon reitzae: AMNH 237345, 1 ex., Venezuela; AMNH
249277, 1 ex., Venezuela.
Tomicodon rupestris: AMNH 239048, 1 ex., Curacao; AMNH
239051, 1 ex., Curacao.
We offer our sincere gratitude to our deep-diving team on
the expedition, M. Lombardi (Ocean Opportunity) and J.
Godfrey (UCONN), who generously collected for us on their
exploratory dives and, as a result, discovered the new
species. We are grateful to the Lee Stocking Island Marine
Institute for logistical support and for assistance with
permits. Thanks to K. Conway (TAMU) for generously
sharing his knowledge of gobiesocids and confirming the
generic placement of the new species, and to R. Schelly and
R. Arrindell (AMNH) for assistance with radiographs. For the
loan of specimens in their care, digital images, and
radiographs, we are grateful to K. Luckenbill, M. Sabaj, and
J. Lundberg (ANSP), and Z. Randall and L. Page (UF). All
research was conducted in accordance with American
Museum of Natural History (AMNH) IACUC guidelines.
This study was supported by Waitt awards from the National
Geographic Society (W140-10) to M. Lombardi and (W101-
10) to D. Gruber, Ocean Opportunity, Inc., the AMNH, New
York, and the National Science Foundation through an
award to JSS (IOS-0749943).
Bo¨hlke, J. E., and C. C. G. Chaplin. 1968. Fishes of the
Bahamas and Adjacent Tropical Waters. First edition.
Livingston, Wynnewood, Pennsylvania.
Bo¨hlke, J. E., and C. C. G. Chaplin. 1993. Fishes of the
Bahamas and Adjacent Tropical Waters. Second edition.
University of Texas Press, Austin, Texas.
Briggs, J. C. 1955. A monograph of the clingfishes (Order
Xenopterygii). Stanford Ichthyological Bulletin 6:iv +224.
Briggs, J. C. 1969. A new genus and species of clingfish
(family Gobiesocidae) from the Bahama Islands. Copeia
Craig, M. T., and J. E. Randall. 2009. Briggsia hastingsi,a
new genus and species of clingfish from Oman. Zootaxa
Fraser, T. H. 1970. Two new species of the clingfish genus
Derilissus (Gobiesocidae) from the western Atlantic.
Copeia 1970:38–42.
Leviton, A. E., R. H. Gibbs, Jr., E. Heal, and C. E. Dawson.
1985. Standards in herpetology and ichthyology: part I.
Standard symbolic codes for institutional resource collec-
tions in herpetology and ichthyology. Copeia 1985:
Sabaj Pe´ rez, M. H. (ed.). 2010. Standard symbolic codes for
institutional resource collections in herpetology and
ichthyology: an Online Reference. Vers. 2.0. American
Society of Ichthyologists and Herpetologists, Washington,
D.C. Electronically accessible at
(accessed 24 June 2011).
Smith-Vaniz, W. F. 1971. Another new species of the
clingfish genus Derilissus from the Western Atlantic
(Pisces: Gobiesocidae). Copeia 1971:291–294.
Smith-Vaniz, W. F., and E. B. Bo¨hlke. 1991. Additions to
the ichthyofauna of the Bahama Islands, with comments
on endemic species. Proceedings of the Academy of
Natural Sciences of Philadelphia 143:193–206.
256 Copeia 2012, No. 2
... Though these fishes are commonly considered small, drab inhabitants of the intertidal zone, in reality, they are remarkably variable and exhibit a stunning range of morphological and ecological diversity (Fig. 1). The smallest clingfishes reach only 10-13 mm standard length (SL) as adults (e.g., Derilissus; Briggs, 1969;Sparks and Gruber, 2012), whereas the largest are 30 times larger at up to 300 mm SL, such as the South American Sicyases sanguineus and the South African Rocksucker, Chorisochismus dentex (Briggs, 1955). The adhesive disc can be a prominent structure that completely spans the belly, comparatively small, or even absent (Springer and Fraser, 1976). ...
... In addition to Eckloniaichthys, our study is also the first to include sequences of a species of the genus Derilissus, with some of the smallest described clingfishes to date. Their tiny maximum recorded sizes for the four described species range from 10.9-27.6 mm SL (Briggs, 1969;Fraser, 1970;Smith-Vaniz, 1971;Sparks and Gruber, 2012) with female individuals as small as 11.3 mm SL already with well-developed eggs and likely capable of reproduction (Briggs, 1969). In the original description of Derilissus, Briggs (1969) outlined his argument for placing this genus either in Diademichthyinae (based on his three-character system) or Gobiesocinae (based on a number of similarities shared by D. nanus, Acyrtops, Eckloniaichthys, and Rimicola) and in the end chose the Gobiesocinae. ...
Full-text available
Gobiesocidae are a moderate-sized family (currently 182 species, 51 genera) of predominantly coastal marine fishes, commonly referred to as clingfishes. Depending on the classification adopted, the species and genera of clingfishes are organized either across ten subfamilies, based on a classification scheme introduced in the 1950s (“traditional” classification, comprising Aspasminae, Cheilobranchinae, Chorisochisminae, Diademichthyinae, Diplocrepinae, Gobiesocinae, Haplocylicinae, Lepadogastrinae, Protogobiesocinae, and Trachelochisminae), or just two subfamilies, in a classification scheme adopted only recently (“reduced” classification, comprising Cheilobranchinae and Gobiesocinae). We investigated the phylogenetic relationships among members of the family Gobiesocidae using both mitochondrial and nuclear DNA sequence data to assess whether the alternative classification schemes (traditional and reduced) are compatible with inferred evolutionary relationships. Phylogenetic hypotheses are derived from maximum-likelihood and Bayesian analyses of a seven-gene concatenated dataset (2 mitochondrial and 5 nuclear markers; 4,857 bp) compiled from individuals representing 82 (of 182) species, 42 (of 51) genera, and 10 (of 10) subfamilies of the Gobiesocidae. Although our investigation provides strong support for the monophyly of the Gobiesocidae, multiple subfamilies of the traditional classification (Aspasminae, Diademichthyinae, Diplocrepinae, Gobiesocinae, and Trachelochisminae), one subfamily of the reduced classification (Gobiesocinae), and multiple genera (Aspasmichthys, Cochleoceps, Lepadogaster, and Lepadichthys) are resolved as non-monophyletic groups. Based on our results and the results of previous studies, we recommend a systematic reassignment of genera between subfamilies, of which we recognize nine: Cheilobranchinae, Chorisochisminae, Diademichthyinae, Diplocrepinae, Haplocylicinae, Gobiesocinae, Lepadogastrinae, Protogobiesocinae, and Trachelochisminae. Membership of the Lepadogastrinae is unchanged from previous usage; the Cheilobranchinae are expanded to contain additional genera from southern Australia, including those placed previously in the Aspasminae (Nettorhamphos and Posidonichthys) and the Diplocrepinae (Barryichthys, Cochleoceps, and Parvicrepis); the Aspasminae are placed in the synonymy of the Diademichthyinae and all genera placed in the former (excluding Modicus and Posidonichthys) are transferred to the latter; the Diplocrepinae are restricted to Diplocrepis; Eckloniaichthys scylliorhiniceps is transferred from the Gobiesocinae to the Chorisochisminae; Gobiesocinae are restricted to the New World members of this group (Acyrtops, Acyrtus, Arcos, Derilissus, Gobiesox, Rimicola, Sicyases, and Tomicodon); the Haplocylicinae are expanded to include additional genera from New Zealand (Gastrocyathus, Gastrocymba, and Gastroscyphus); the Protogobiesocinae are expanded to accommodate three genera of deep water taxa (Gymnoscyphus, Kopua, and Protogobiesox); and the Trachelochisminae are restricted to Dellichthys and Trachelochismus. Four genera (Aspasmogaster, Conidens, Creocele, and Modicus) of uncertain placement are not assigned to any subfamily herein and are considered incertae sedis within the Gobiesocidae.
... Over seventy percent of the descriptions of new species of clingfishes published in the last ten years are based only on one or two individuals (e.g., Hutchins, 2006;Randall, 2008, 2009;Moore et al., 2012;Sparks and Gruber, 2012;Fricke, 2014;Craig et al., 2015;Shinohara and Katayama, 2015;Hastings and Conway, 2017). In the majority of these descriptions, the internal (skeletal) anato- my of the newly described species has gone undocumented or documented only superficially via radiographs (e.g., Moore et al., 2012;Sparks and Gruber, 2012;Shinohara and Katayama, 2015;Hastings and Conway, 2017), likely due to valid concerns regarding damage to type material. ...
... Over seventy percent of the descriptions of new species of clingfishes published in the last ten years are based only on one or two individuals (e.g., Hutchins, 2006;Randall, 2008, 2009;Moore et al., 2012;Sparks and Gruber, 2012;Fricke, 2014;Craig et al., 2015;Shinohara and Katayama, 2015;Hastings and Conway, 2017). In the majority of these descriptions, the internal (skeletal) anato- my of the newly described species has gone undocumented or documented only superficially via radiographs (e.g., Moore et al., 2012;Sparks and Gruber, 2012;Shinohara and Katayama, 2015;Hastings and Conway, 2017), likely due to valid concerns regarding damage to type material. Our description of Nettorhamphos radula is also derived from a small number of individuals (holotype and single paratype only), but contrary to these previous descriptions we have used a combination of traditional radiography and CT scanning to almost fully document the skeletal anatomy of the individuals of the type series. ...
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Nettorhamphos radula, new genus and species, is described from two specimens, 20.3–40.2 mm SL, trawled from sponge and algae reefs between 30–40 meters in depth offshore from Fremantle, Western Australia. The new taxon is distinguished from all other members of the Gobiesocidae by having vast fields of tiny conical teeth throughout the oral jaws that are arranged in multiple, regular rows along the lingual surface of the premaxilla and the dentary. The new taxon is tentatively considered a close relative of two other southern Australian endemic clingfish taxa (Posidonichthys and the undescribed ‘‘Genus A’’) based on the presence of a well-developed and heavily ossified subopercular bone that articulates strongly with both the opercle (dorsally) and the preopercle (anteriorly).
... In the central and western Pacific CCRs are commonly used to record quantitative depth-distribution data throughout most of the mesophotic zone of reefs (e.g., Fukunaga et al., 2017;Coleman et al., 2018;Pinheiro et al., 2019b) and also to collect specimens of new species of deep-reef fishes (e.g., Pyle, 2000;Pinheiro et al., 2019b;Shepherd et al., 2020;Tea et al., 2020). However, there has been little actual collecting of reef fishes using this technique in the Greater Caribbean (Starck and Colin, 1978;Sparks and Gruber, 2012), with somewhat more collecting activity in Brazil (Pimentel et al., 2020). ...
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Understanding the diversity and ecology of deep-reef fishes is challenging. Due to intensive and widely dispersed sampling, the Greater Caribbean (GC) fauna of species found on shallow reefs is much better characterized than the fauna of deep-reef species restricted to mesophotic (40–130 m) and rariphotic (130–300 m) depths. Our knowledge about deep-reef fishes is based on ship-board sampling and the recent use of rebreather diving, remotely operated vehicles (ROVs), baited remote underwater videos, and crewed submersibles. Submersible research on GC deep-reef fishes began in the 1960s and has flourished over the last decade through research by the Smithsonian Institution’s Deep Reef Observation Project (DROP). Here we quantify the contribution of submersible research, particularly the surge by DROP, to our understanding of the diversity of the deep-reef fish fauna of the GC. We compared shallow- and deep-reef fish faunas of three GC sites subjected to DROP research to faunas of three sites without such research. DROP increased the size of the deep faunas at three islands ∼9-fold, and they have deep-reef faunas ∼2–4 times the size of those of the other three sites. Those deep-reef faunas have high proportions of small cryptobenthic fishes, which also represent a major component of shallow faunas. That research increased the rate of discovery (collection) of new species of deep-reef fishes ∼6-fold and accounts for 31% of the deep-reef species first discovered within the GC. Substantial numbers of new species at each of the three DROP islands were not found at the other two. This indicates that other parts of the GC likely harbor many undetected deep-reef fishes, and that the size of the deep-reef fauna of the GC is significantly underestimated. These results show that small research submersibles are versatile, highly productive tools for deep-reef studies. They allow long-duration dives at any depth, while offering unparalleled views of their surroundings to study the ecology of deep-reef fishes (e.g., DROP’s definition of the rariphotic assemblage from fish depth distributions). Submersibles can efficiently collect reef fishes of a broad range of taxa, ecotypes and sizes, leading to a more comprehensive understanding of the regional GC deep-reef fish fauna.
... confirm that this species is an inhabitant of mesophotic coral reefs (i.e., largely tropical, light-dependent communities found between 30-150 m depth; Loya et al., 2019). Gobiesocids are rarely encountered in mesophotic coral reef ecosystems, and in addition to F. akiko, other mesophotic coral reef-dwelling gobiesocids include the members of the new world genus Derilissus (which contains five species, D. altifrons, D. kremnobates, D. lombardii, D. nanus, and D. vittiger ;Briggs, 1969b;Fraser, 1970;Smith-Vaniz, 1971;Sparks and Gruber, 2012) and potentially also certain eastern tropical Atlantic members of the genus Diplecogaster (including D. ctenocrypta and D. tonstricula; Fricke et al., 2015). ...
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A new genus and two new species of Indo-Pacific clingfishes are described in this study. The new genus, Flabellicauda, belongs to the Diademichthyinae and can be distinguished from other genera currently placed in this subfamily by the following combination of characters: snout moderate in length and slightly pointed, not extremely long or strongly rounded; oral cleft very small, restricted to anterior tip of snout, posterior portion of both jaws covered by thick skin of snout; gill opening a tiny, narrow slit, dorsalmost point level with base of 9th to 14th (usually 12th, rarely 9th) pectoral-fin ray in lateral view; gill membrane attached to isthmus; two rows of gill filaments on gill arches 1–3; extremely small “single” adhesive disc, its length 8.1–13.5% SL; center of disc flat, without cavity; disc papillae flattened, similar in size across disc surface; preopercular lateral line canal and associated pores absent; dorsal, anal, and caudal fins connected via thin membrane, giving appearance of single, continuous median fin around posterior part of body; and upper and lower hypural plates completely fused, forming large fan-like hypural complex. Two new species are described and assigned to Flabellicauda, including F. alleni, new species (type species of Flabellicauda), and F. cometes, new species. Two additional species previously assigned to Lepadichthys are also transferred to Flabellicauda, including F. bolini, new combination, and F. akiko, new combination. Among species of Flabellicauda, F. akiko is unique in having the following characters: head sensory canal pores poorly developed, including 1 nasal and 1 postorbital pore (vs. usually 2 nasal, 2 lacrimal, and 2 postorbital pores in F. alleni, and F. bolini; 2 nasal pores in F. cometes); upper end of gill opening level with base of 9th or 10th pectoral-fin ray in lateral view (vs. 12th to 14th); disc region A with papillae at center (vs. disc region A without papillae at center); and body background color red in life, with white stripes along body (vs. body background color black or marron in life, with white stripes along body). Although F. alleni is very similar to F. bolini, the former differs from the latter in having a higher number of gill rakers (viz., 5–8 [modally 6, rarely 5], 6–8 [6], and 6–8 [7] on the first, second, and third gill arch, respectively, and 18–24 [19] total gill rakers [first + second + third arch] in F. alleni vs. 4–6 [5] on the first, second, and third arch, respectively, and 12–17 [14] total gill rakers in F. bolini). In addition to the meristic difference, head length, pre-disc length, orbit diameter, and caudal-peduncle length and width proportions further aid to distinguish F. alleni from F. bolini. Examined specimens of F. alleni were collected from Sri Lank and southeast Asia whereas those of F. bolini were collected from Papua New Guinea, Vanuatu, and Fiji and the range of the two species are not known to overlap. Flabellicauda cometes can be easily distinguished from F. alleni and F. bolini in having the following characters: 10–12 dorsal-fin rays (vs. 12–15 [13]); 9–11 anal-fin rays (vs. 10–13 [11], rarely 10); head sensory canal pores poorly developed, including 2 nasal and 1 postorbital pores. Notes on the ecology of each of the four species of Flabellicauda are also provided.
... Recent data now suggests that the majority of reef-dwelling fish species are not true depth generalists, and although some shallow species may reach mesophotic depths, most are more abundant at one strata or another (Muñoz et al., 2017;Thresher and Colin, 1986;Rocha et al., 2018). Stratification of reef fishes is also supported by the continued high yield of new species discoveries in the mesophotic zone, even in regions that have been thoroughly surveyed at shallower depths (Pyle, 2000;Sparks and Gruber, 2012). However, these deep reefs are hypothesized to be just as vulnerable as their shallow water counterparts to both natural and human-mediated impacts and further study and increased conservation is essential to their survival (Appledoorn et al., 2015). ...
Mesophotic coral reefs (~30–150 m) and deeper reefs (>150 m) represent some of the least explored and poorly documented habitats in our oceans. These deep ecosystems are both high in biodiversity and ecologically distinct from shallower reefs. They are also equally threatened by natural and anthropogenic factors. Thanks to advancements in remote undersea technologies, our access to and understanding of these poorly studied environments continues to expand. With current data now suggesting more stratified populations of reef fishes and a continuous yield of new species discovered in the mesophotic zone, now under global pressures of climate change and overfishing, the need to explore these ecosystems has never been greater. Most deep-sea (>200 m) biodiversity studies rely on dredging and trawling technologies that are not selective or targeted. Here we present on the design and field demonstration of a compact, low-cost, targeted reef fish sampling system intended for use on inspection-class ROVs in the mesophotic zone. During a research expedition to the Western Province of the Solomon Islands, the system successfully collected multiple novel fish species at depths ranging from 90 to 187 m. The results obtained during this expedition highlight the utility of ROV-based collecting systems, add to the growing knowledge of mesophotic reef communities, and inspire new techniques for sampling mobile faunas at depth.
... Still, due to their cryptic ecology, it is not surprising that the majority of recent genus and species descriptions are based on the investigation of a few individuals only (e.g., Conway et al., 2017b). Whereas some of these taxonomical and systematic studies use more classical approaches (e.g., Fricke, 2014;Fricke et al., 2010Fricke et al., , 2015Fricke & Wirtz, 2017Sparks & Gruber, 2012), many authors include more comprehensive morphological (e.g., micro-computed tomography imaging) and/or genetic (e.g., single locus DNA barcoding) methods, which altogether turn out to be effective tools for delineating clingfish species (e.g., Almada et al., 2008;Bileceno glu et al., 2017;Conway et al., 2014Conway et al., , 2017aConway et al., c, 2018Conway et al., , 2019Fujiwara et al., 2018;Fujiwara & Motomura, 2018a,b, 2019Henriques et al., 2002). ...
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The clingfish (Gobiesocidae) genus Gouania (Nardo 1833) is endemic to the Mediterranean Sea and inhabits, unlike any other vertebrate species in Europe, the harsh intertidal environment of gravel beaches. Following up on a previous phylogenetic study, we revise the diversity and taxonomy of this genus, by analysing a comprehensive set of morphological (meristics, morphometrics, micro computed tomography imaging), geographical and genetic (DNA‐barcoding) data. We provide descriptions of three new species, G. adriatica sp. nov., G. orientalis sp. nov., G. hofrichteri sp. nov. as well as re‐descriptions of G. willdenowi (Risso 1810) and G. pigra (Nardo 1827) and assign neotypes for the latter two species. In addition to elucidating the complex taxonomic situation of Gouania, we discuss the potential of this enigmatic clingfish genus for further ecological, evolutionary and biodiversity studies that might unravel even more diversity in this unique Mediterranean fish radiation.
... , b;Baldwin and Weigt 2012;Sparks and Gruber 2012;Walsh and Tanaka 2012;Carvalho- Filho and Ferreira 2013;Pyle and Earle 2013; Robertson 2014, 2015;Fukui and Motomura 2014; Copus et al. 2015a, b;Stiller et al. 2015;Anderson et al. 2016; Baldwin et al. 2016a, b;Carvalho-Filho et al. 2016;Pyle and Kosaki 2016;Sinniger et al. 2016;Tea et al. 2016;Tornabene et al. 2016b;Anderson and Johnson 2017;Conway et al. 2017;Easton et al. 2017Easton et al. , 2018Easton et al. , 2019Hastings and Conway 2017;Motomura et al. 2017;Prokofiev 2017;Rocha et al. 2017;Tornabene and Baldwin 2017;Walsh et al. 2017;Winterbottom 2017; Montgomery et al. 2019), algae (Norris and Olsen 1991;Ballantine and Norris 1994; Aponte 1996, 2002; Ruiz 2010, 2011;Athanasiadis et al. 2013;Tsuda et al. 2015;Spalding et al. 2016Spalding et al. , 2019a, anthozoans(Vermeij et al. 2003;Tu et al. 2012; Guzman 2013, 2016;Randall 2015;Kise and Reimer 2016;Samimi-Namin et al. 2016;Benayahu et al. 2017Benayahu et al. , 2019Rowley et al. 2019), other invertebrate groups ...
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Although the existence of zooxanthellate corals in mesophotic coral ecosystems (MCEs; light-dependent coral ecosystems from 30 to 150 m in depth) has been known since the nineteenth century and focused scientific exploration of MCEs began over 50 years ago, more than 70% of all research on MCEs has been published only within the past seven years. MCEs represent approximately 80% of potential coral reef habitat worldwide, yet very little is known about them in comparison to shallow reefs. Many MCE species new to science have been discovered in the past decade, and many more await discovery. The term MCEs has been widely adopted by the scientific community since its 2008 inception; however, there is considerable inconsistency in how it is subdivided into “upper” and “lower” (and sometimes “middle”) zones. Moreover, doing so may lead to artificial boundaries when habitats and ecological communities at different depth zones may blend together. Growing evidence suggests that MCEs harbor proportionally more geographically endemic species than their shallow-water counterparts, and initial indications are that major biogeographic patterns described for shallow reef organisms may not apply to MCEs. Although MCEs may serve as refugia for some shallow species, they are increasingly recognized as unique ecosystems, important in their own right. Future research on MCEs should aim to address gaps in our understanding of the basic physical and biological characteristics of MCEs including geography, taxonomic composition, depth distribution, ecology, physiology, and connectivity. Improving knowledge of MCEs would benefit from combining different technologies to leverage the strengths of each.
The one-dimensional deformation of shape memory alloy (SMA) wires and springs can be implemented into different types of functional structures with three-dimensional deformations. These structures can be classified based on the type of structure and how the SMA element has been implemented into the following categories: rigid mechanical joints, semi-rigid flexural hinges, SMA elements externally attached to a soft structure, and embedded into the soft structure. These structures have a wide range of properties and implementation requirements, and they have been used to produce a variety of robots with rigid and soft motions. The different research efforts to develop actuators and robots related to each type of structure are presented along with their respective strengths and weaknesses. A model is then developed to discuss the performance and applicability of SMA wires versus SMA springs for actuators with a polymeric matrix to see the effect of each type of SMA on the selection of design parameters. A comparison of the different types of structures and the applicability of different types of SMA elements for different types of structures is then presented.
The unusual clingfish Protogobiesox asymmetricus n. gen, n. sp. is described on the basis of 4 specimens collected in deep water off the north coast of Papua New Guinea in 2012. The species is characterized by its 9-10 dorsal rays, 8 anal rays, 17-24 pectoral-fin rays, 15 principal caudal-fin rays, 3 gills, third arch with 3 gill rakers, 34-35 total vertebrae, with asymmetrical lateral bending starting behind the skull, bent at an angle of 85°-92°; skull asymmetrical in frontal view; skin naked, surface of head and body without striae; disc without adhesive papillae. A new subfamily Protogobiesocinae is described for this species and Lepadicyathus mendeleevi Prokofiev, 2005 which is redescribed. The new subfamily is compared within the family; keys to the subfamilies of Gobiesocidae and the species within the new subfamily are presented; its phylogenetic relationship to other gobiesocids is inferred based on a multi-locus DNA dataset.
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Two new species of the clingfish genus Derilissus are described from the Caribbean Sea. Notes on the color pattern, pore system, osteology, and ecology are given and these species are compared with the only other species presently known in this unusual gobiesocine genus.
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Briggsia hastingsi is described as a new genus and species of gobiesocid fish from a single specimen, 22 mm in standard length, collected in 2 m depth on the southeastern coast of Oman. The genus differs principally from other aspasmine genera in having fewer dorsal- and anal-fin rays (4 each) and a shorter head (head length 2.5 in standard length).
A tiny, new species of clingfish, Derilissus nanus, from the Bahamas also represents a new genus. Because of an interesting evolutionary convergence, the new genus would, on superficial characters, be placed in an Indo-West Pacific subfamily. However, its osteology indicates that it is a derivative from a New World stock and that it should be placed in the subfamily Gobiesocinae. Its relationships within the subfamily are considered.
A new species of the clingfish genus Derilissus is described from off Dominica. Comparison with its congeners reveals that the new species is most closely related to D. nanus. A reduced number of pectoral-fin rays and disk papillae suggest that D. nanus is the most specialized member of the genus.
Additions to the ichthyofauna of the Bahama Islands, with comments on endemic species
  • W F Smith-Vaniz
  • E B Böhlke
Smith-Vaniz, W. F., and E. B. Böhlke. 1991. Additions to the ichthyofauna of the Bahama Islands, with comments on endemic species. Proceedings of the Academy of Natural Sciences of Philadelphia 143:193-206.
Standard symbolic codes for institutional resource collections in herpetology and ichthyology: an Online Reference. Vers. 2.0
  • Sabaj Pérez
Sabaj Pérez, M. H. (ed.). 2010. Standard symbolic codes for institutional resource collections in herpetology and ichthyology: an Online Reference. Vers. 2.0. American Society of Ichthyologists and Herpetologists, Washington, D.C. Electronically accessible at (accessed 24 June 2011).