RECORDS OF ANGLERFISHES ( ACTINOPTERYGII : LOPHIIFORMES : LOPHIIDAE ) FROM INDONESIA

Background. The lophiid anglerfi shes are with commercial importance, but rarely they are documented in Indonesian waters. During the Japanese and Indonesian collaborative surveys in 2004 and 2005, an anglerfi sh collection was made and it is the aim of this study to identify this collection, to document new records and to provide information further application usage such as fi shery assessment from the study area. Materials and methods. Specimens were deposited in the HUMZ collection and examined by the authors. Counts, measurements, and photography were consistent with the commonly used methods. Results. Three genera and eight species in the family were collected, including Sladenia cf. zhui [sensu Ni, Wu et Li, 2012]; Lophiomus setigerus (Vahl, 1797); Lophiodes naresi (Günther, 1880); Lophiodes bruchius Caruso, 1981; Lophiodes endoi Ho et Shao, 2008; Lophiodes lugubris (Alcock, 1894); Lophiodes miacanthus (Gilbert, 1905); and Lophiodes triradiatus (Lloyd, 1909). Of these, Sladenia cf. zhui, L. bruchius, L. endoi, L. lugubris, and L. miacanthus, are described in detail. Conclusion. The diversity of the lophiid anglerfi sh fauna is relatively low from the eastern Indian Ocean side of Indonesia. All species treated in the presently reported study represent the fi rst records in Indonesian waters. A discussion of lophiid fauna from Indonesia is provided, along with a key to known species in Indonesia.


INTRODUCTION
The lophiid anglerfi shes are commercially important fi shes that inhabit the sea bottom at depths of several meters to about 1500 m in all major oceans.Some species in the genus Lophius can grow to ca. 1.5 meters total length and are sold as high-priced seafood, whereas most species attain about 40 cm and are of less commercial importance.
The family currently comprises four genera and about 28 valid species.About 14 species representative all four genera inhabit the Indo-west Pacifi c region (Caruso 1999;Ho et al. 2011Ho et al. , 2014)).Only a few species were thought to occur in Indonesian waters, e.g.Lophiomus setigerus, Lophiodes gralicimanus and Lophiodes mutilus (Caruso 1999).
In 2004 and 2005, the Overseas Fishery Cooperation Foundation, Japan, and the Agency for Marine and Fisheries Research, Rep ublic of Indonesia, conducted the Japan and Indonesia Deep Sea Fishery Resources Joint Exploration Project in deep waters off Sumatra and Java, in the eastern Indian Ocean.The aim of this joint exploration was to identify and develop unused deep-sea fi shery resources in this area.To accomplish this purpose, two cruises between 1 September and 30 October, 2004 and three cruises between 2 May and 14 August, 2005 were carried out by the Indonesian research vessel, Baruna Jaya IV.During this exploration, more than 400 fi sh species were collected (Ho et al. 2015(Ho et al. , 2016)).
Among the fi shes collected were 10 specimens of the anglerfi sh family Lophiidae, representing seven species in three genera.The purpose of this publication is to document the occurrence of these species in Indonesian waters, to provide a detailed descriptions of each species, and to provide a key to their identifi cation.

METHODS AND MATERIALS
Methods for taking measurements and the terminology used generally follow Caruso and Bullis (1976) and Caruso (1981).In addition to those measurements used in the above references, the following measurements were recorded for Sladenia: eye diameter as the width of the clear window; inter-opercle and inter-palatine distances were measured from the outer base of the spines or bumps on both sides; upper jaw length is the distance from the upper jaw symphysis to lower margin of the maxilla; and caudal fi n is measured from the posterior edge of the hypural to the distal margin of the fi n.All specimens reported were deposited in the fi sh collection of Hokkaido University Museum, Hokadate (HUMZ).Institutional abbreviations follow those listed in the Catalog of Fishes (online version, Eschmeyer, 2016).

RESULTS
Family Lophiidae Rafi nesque, 1810 Genus Sladenia Regan, 1908Sladenia Regan, 1908: 250 (type species: Sladenia gardineri Regan, 1908, by monotypy).Remarks.This is a very poorly known genus with four nominal species, none of which are well represented in collections.The known species have been described from few specimens and individual variation is still poorly understood.The two specimens from the current collection resemble a recently described species, Sladenia chui Ni, Wu et Li, 2012.However, since there are some differences, the identifi cation is only tentative.
Underwater photographs taken by submersibles show individuals of Sladenia on rocks, rocky areas or deep coral reefs, which may explain the relatively few specimens in collections.This is new record for the genus in Indonesian waters.
Body slightly elongate, rather muscular, with slight hump on back.Head globular.Tail strong and cylindrical, gradually compressed posteriorly.Mouth large, its cleft oblique to nearly vertical.Lower jaw extended forward, well in advance of the upper jaw; posterior end of upper jaw not reaching vertical at anterior margin of eye.Eye relatively small, covered by transparent skin, directed laterally and slightly dorsally.
Anterior portion of frontal with fl at dorsal process, its anterior end slightly elevated; posterior portion of frontal with plate-like process directed outward laterally, forming a right angle.Frontal and sphenotic spines both relatively blunt, but better developed than other cranial spines.Dorsal surface of premaxilla, palatine, outer sphenoid, pterotic, dorsal end of opercle, hyomandibula and quadrate with visible/feeble low bumps.Blunt, broad-based symphysial spine on lower jaw.Preopercle, subopercle, humeral, parietal and articular without spines or bumps.
Illicium slender and fi lamentous, its length 36.0-37.0%SL; no esca; second dorsal spine short, 15.9-19.7%SL, about half length of illicium.Two post-cephalic spines, almost completely contained within loose fold of skin.Soft dorsal fi n base short, at posterior one-third of body, covered by loose skin from base to about two-thirds of its height, proximal half of posterior margin of last ray connected by loose skin to base of caudal fi n.Pectoral-fi n base with long pterygial bones, its length about two times that of longest fi n ray.Anal fi n covered by loose skin from base to about three-fourths of its height, proximal half of posterior margin of last ray connected by loose skin to  Teeth on vomer and palatine conical to fanglike, distinctly larger than those on jaws.Two to four teeth on each side of vomer; largest teeth, usually innermost, fi xed, the rest depressible.Single irregular row of 6-7 teeth on palatine.Upper jaw with outer row of smaller teeth along entire length; short, irregular rows of slightly larger teeth along inner one-third of jaw, innermost tooth largest and fi xed, the rest depressible.Lower jaw with about 3-4 rows of depressible teeth, those on inner row longest.
Opercle deeply forked, both lobes about equal in length.Subopercle slender, overlaps by the lower end of lower branch of opercle; dorsal margin of subopercle with bluntly pointed process, anterior end bluntly pointed, posterior portion slender and tapering, fi lamentous distally.Coloration.Uniformly brownish.Margins around mouth, including space between maxilla and premaxilla and lower lip pale.Peritoneum black.Mouth cavity pale, with some light grayish patches on fl oor of mouth and/or tongue.Remarks.The presence of two post-cephalic spines and the uniformly brown coloration indicate a close resemblance between the two Indonesian specimens and S. chui.However, Ni et al. (2012) diagnosed S. chui by its very broad snout (11.7-13.1% SL or 29.2-34.6% of head length), whereas the Indonesian specimens have a narrow snout respectively) that falls within the range of other congeners.In fact, the snout width provided by Ni et al. (2012) is far broader than any lophiid species and that may be attributed to different landmarks interpreted by the authors.An attempt to examine the type series in the Shanghai Ocean University has been unsuccessful.

Lophiomus setigerus (Vahl, 1797)
Fig.  Body depressed, forming rounded disk comprising head and anterior portion of body; tail muscular, depressed.Dorsal surface of frontal and premaxilla with low knoblike spines.Palatine with 2 spines, posterior distinctly larger than anterior.Upper end of each premaxilla with a bifurcate spine, smaller than those of palatine.Blunt symphysial spine on lower jaw.Two sharp spines posteriorly on posterior margin of frontals.
Two sharp spines on sphenotic, outer about twice size of inner.Inner frontal spine a feeble bump.Hyomandibular spines reduced in larger specimen, slightly developed in smaller.Pterotic spines blunt with broad base.A sharp spine halfway onto preopercle.Lower end of subopercle with sharp spine.Single epiotic spine well developed.Humeral spine well developed, multifi d.
Illicium reaching slightly beyond epiotic spines.Second dorsal-fi n spine shorter than illicium, with very broad pigmented membranes, reaching inner sphenotic spines in small specimen, extending to slightly beyond the spines in larger specimen.Third dorsal-fi n spine short in larger specimen, which might be result of damage, reaching humeral spine; longer in smaller specimen, reaching slightly beyond base of sixth dorsal spine.Fourth dorsal-fi n spine slender, slightly beyond tip of following two spines.Fifth and sixth dorsal-fi n spines short, mostly covered by skin, both not reaching origin of soft dorsal fi n.When fully folded back, anal fi n not reaching base of caudal fi n.Body depressed, head broad; oval in dorsal view.Dorsal surfaces of frontal and premaxilla smooth, without bumps, except for low bump on dorsal surface of upper portion of premaxilla.Posterior margin of frontal bluntly serrate, posteriormost spine directed slightly outward.Sixth dorsal-fi n spine short, about half length of fi fth, not reaching origin of soft dorsal fi n.
Upper jaw with long outer row of small fangs, those on medial portion directed forward and downward; short irregular inner row of teeth on medial one-third of jaw, slightly larger than those of outer row, innermost teeth on each side fi xed, the rest depressible.All teeth on vomer and palatine fi xed, teeth present on outer corner of vomer and along palatine.Lower jaw with about 4 rows of teeth, those on inner row longest.Anal fi n reaching base of caudal fi n when fully folded back.Coloration.Dorsal surface uniformly brownish, with some dark fl aps.Pectoral fi n slightly darker than body, with broad white margin.Dorsal fi n slightly paler than body.Ventral surface paler than that of dorsal surface, but with fi ne pigmentation.Pelvic fi n with base slightly darker than rest fi n and with broad white margin; caudal fi n base deep brown, paler distally.Distribution.Majority of specimens collected from western and central Pacifi c Ocean.Our specimen was collected in the eastern Indian Ocean off Indonesia, which represents the fi rst record of this species in the area.Remarks.This species is easily confused with a similar species, Lophiodes insidiator.Records of the latter from western Pacifi c Ocean need further investigation.
Body depressed, tail muscular, laterally depressed; head broad, oval in dorsal view.Dorsal surface of frontal and premaxilla smooth, without bumps, except for a small bump on dorsal surface of upper portion of premaxilla.Posterior frontal ridge with 3 spines, posteriormost largest, sharp, slightly curved laterally.Inner frontal spine present.
Palatine with 2 sharp spines, posterior spine bout twice length of anterior one.Sphenotic with two spines, inner spine sharp and long, straight; outer spine short and pointed on right side, blunt on left side.Hyomandibular with two short but sharp spines, posterior spine larger.Opercular spine short but sharp.Preopercular spine sharp and long.Two spines on subopercle, outer about twice length of inner.Humeral spine subdivided into four spines distally.Blunt spine on quadrate.Two blunt spines on articular.Cleithral spine blunt.
Illicium reaching slightly beyond base of third dorsalfi n spine.Esca a small bulb, bearing distal cirrus.Second dorsal-fi n spine reaching cleithral spine.Third dorsal-fi n spine broken distally, remaining part extending to base of sixth soft dorsal-fi n ray.Half of fi fth dorsal-fi n spine exposed, short, not reaching origin of soft dorsal fi n.Sixth dorsal spine completely embedded in skin.
Teeth on vomer and palatines about same size of those on jaws.Teeth on premaxilla arranged in longer row on outer margin, those on inner portion of premaxilla slightly longer and directed forward; a short posterior row of slightly longer teeth on inner one-third of bone, the innermost tooth (second innermost on right side) fi xed, the remaining teeth depressible.Lower jaw with three rows of straight teeth, those in innermost row longest.Anal fi n extending well beyond the caudal fi n base when fully folded back.Our specimen represents the fi rst record of the species in the eastern Indian Ocean.
Remarks.Ho et al. (2011) reported a specimen of this species from the Marquesas Islands of Polynesia, whereas all other specimens were obtained from the Kyushu-Palau Ridge and Hawaiian Islands (Ho and Shao 2008).They (Ho et al. 2011) indicated the differences in the Marquesas specimen: a single terminal cirrus on the esca (vs.more than 5 in the northern Pacifi c specimens) and one extra pair of small tendrils on the third dorsal-fi n spine (vs.only one pair of tendrils).The Indonesian specimen also has only one terminal cirrus on the esca.However, the skin of the third dorsal-fi n spine of this specimen is damaged and tendrils have been lost.
Two teeth on each lateral corner of vomer; palatines with an irregular row of 8 teeth.Teeth on maxilla in one outer row; those on mesial side slightly longer and directed forward; short inner row of teeth with slightly longer teeth than those of outer row, all depressible, except for second innermost of right side (none on left side) fi xed.Lower jaw with three rows of teeth, those of innermost row longest.Anal fi n extending well beyond caudal-fi n base when folded back.
Coloration.Body uniformly deep brown; dorsal surface of pectoral fi n darker with pale margin.Dorsal surface with some small pale spots, each with black cirrus.Ventral surface lightly pigmented.Peritoneum black.Color of esca matching dorsal background.Distribution.Previously known from the western and southern Pacifi c Ocean off Japan, Taiwan and New Caledonia, and from eastern Indian Ocean off western Australia.The specimen represents a new record for Indonesia.Remarks.Although the third dorsal-fi n spine of the Indonesian specimen is slightly shrunken, it clearly has two black skin patches on the upper one-third of the spine.As mentioned in Ho et al. (2011), the only specimen of L. bruchius collected in Polynesia also has one additional pair of small tendrils on the distal portion of the spine.This difference may represent geographic variation.
Body depressed; tail muscular, laterally depressed.Head broad, rounded in dorsal view.Dorsal surfaces of frontal and premaxilla smooth without bumps.Posterior frontal ridge with 3 spines, all blunt.
Palatine with two sharp spines, posterior slightly larger than anterior spine.Inner sphenotic spine sharp and long, straight; outer sphenotic spine blunt, broad.Hyomandibula with two short, sharp spines, anterior spine larger.Opercle with short blunt spine.Preopercle with long sharp spine on left side; spine absent on right side.Two spines on subopercle, posterior spine slightly larger than anterior spine.Humeral spine divided into 4 branches.Quadrate with blunt spine.Articular with two blunt spines.Cleithral spine blunt.
Illicium reaching slightly beyond base of sphenotic spines, but not reaching base of third dorsal-fi n spine.Esca a small narrow bulb, with terminal cirrus.Second dorsal-fi n spine reaching base of humeral spines.Third dorsal-fi n spine reaching base of fi fth ray of soft dorsal fi n; no clear black tendril on spine, but some transparent membrane present.Fifth and sixth dorsal-fi n spines exposed distally, not reaching origin of soft dorsal fi n.Dorsal surfaces of frontal and premaxilla smooth, without bumps.Posterior frontal ridge with 3 spines; posteriormost spine sharp, slightly curved outwardly, and slightly larger than the other two spines.Inner frontal spine present.Palatine with two sharp spines, posterior spine about twice size of anterior one.
Two teeth on each lateral corner of vomer; irregular row of 8 or 9 teeth on palatine; all teeth fi xed.Teeth on maxilla with outer row on margin, those on mesial side slightly longer and directed forward; one short irregular inner row, slightly longer than that of outer row; innermost tooth fi xed, others depressible.Lower jaw with three rows of straight depressible teeth, those in innermost row longest.Anal fi n extended well beyond the caudal fi n base when fully laid back.
Coloration.Body uniformly deep brown with many irregular black patches; dorsal surface of pectoral fi n darker, with pale margin.Illicium, second and third dorsal spines deep brown.Esca transparent.Ventral surface brownish gray.Peritoneum black.Distribution.Previously known from the central north, northwestern and tropical Pacifi c Ocean.New record for Indonesia.Remarks.Ho andShao (2007, 2008) recorded this species from Taiwan and Kyushu-Palau Ridge, respectively, and Ho et al. (2011) recorded this species from the tropical Pacifi c Ocean.In contract to specimens from elsewhere, the illicium of the Indonesian specimen is brownish, rather than black and this specimen has only 18 rays in each pectoral fi n.The black color of other specimens of L. miacanthus do not appear to fade after preservation and the relatively few pectoral-fi n rays have not been observed in previous studies (19 or 21 in Caruso 1981;22 in Ho et al. 2011).As more specimens may support the recognition of the Indonesian population as a different species, the identifi cation is regarded as provisional.Remarks.The specimen examined is a juvenile with welldeveloped fi ns and spines.It has only one post-cephalic spine (assumed to be the fi fth dorsal-fi n spine) and has no trace of the last dorsal-fi n spine (assumed to be sixth).Alcock (1894) described Lophius lugubris from India, which he diagnosed as having only four dorsal-fi n spines (i.e.only one post-cephalic spine), except for one syntype that lacks all post-cephalic spines.Caruso (1981) recognized ZSI F13467 as the holotype of L. lugubris and treated it as junior synonym of Lophiodes mutilus.However, according to Alcock (1894), three lots of specimens were used in his description.The fi rst author of present paper examined two other syntypes, ZSI F670/1 and ZSI F671/1, both listed as non-types by Caruso (1981).The former specimen has one post-cephalic dorsal-fi n spine and the latter has none, which is consistent with Alcock's original observation.The illicium of ZSI F671/1 is damaged, but the third dorsal-fi n spine is long (58.0%SL), and the specimen has other characters that distinguish it from L. triradiatus.The fi rst author of present paper examined a series of Indian specimens (n = 21) that consistently have four dorsalfi n spines, whereas all specimens of L. mutilus (and two closely-related species, L. iwamotoi and L. maculatus) consistently have fi ve dorsal-fi n spines (e.g. 2 post-cephalic spines).Hence, we recognize Lophiodes lugubris as a valid species.One of the syntypes, ZSI F13467 is presumed lost.

DISCUSSION
As mentioned above, only a few lophiid species have been recorded from Indonesian waters, namely Lophiomus setigerus, Lophiodes gralicimanus and Lophiodes mutilus (Caruso 2002).Surprisingly, not many lophiid specimens were collected in the 138 hauls made over a period of about seven and half months during the present study.
Only two specimens of Lophiomus setigerus were collected during the survey, despite the fact that the species is the most common lophiid species in the Indo-west Pacifi c region [during all seasons].Only one specimen each of Lophiodes triradius and Lophiodes naresi were collected during this survey although a good number have been regularly collected in the western Pacifi c Ocean (Ho and Shao 2007;Ho et al. 2009Ho et al. , 2011Ho et al. , 2014)).
Only one specimen each of L. endoi, L. miacanthus and L. bruchius were collected in the eastern Indonesian region, corresponding with the results of Ho et al. (2011).These three species may be more abundant in waters further north around Taiwan and Japan than in the tropical Pacifi c region.
By contrast, no specimens identifi able as Lophiodes mutilus were collected during the survey.According to personal observations of the fi rst author, L. mutilus (now recognized as a species complex; Ho, unpub.data) is far more common compared to other congeners in areas such as South Africa, Taiwan, Japan and Australia.
In summary, the low density of lophiid anglerfi shes in the eastern Indian Ocean region off Indonesia differs from that observed in oceanic water of many other countries of the Indo-west Pacifi c region.More investigations are needed to understand the fi sh fauna of this region.

Lophiodes Goode et Bean, 1896
Lophiodes Goode et Bean, 1896: 537 (type species: Lophius mutilus Alcock, 1894, by monotypy).Remarks.The most specious genus of the family, with 17 nominal species distributed in all major oceans.Five species from Indonesian waters are recognized in this study.