ArticlePDF Available

A new genus and species of Bythitidae (Teleostei: Ophidiiformes) from northwestern Australia

Authors:

Abstract and Figures

A new genus and species of bathyal bythitid fish (Teleostei: Ophidiiformes) is described based on a single specimen caught at a depth of 392 m in the Timor Sea off the coast of northwestern Australia. Timorichthys disjunctus gen. nov., sp. nov. differs from all other bythitid genera by the position of the anus midway between the tip of the snout and origin of the anal fin. The joined vertical fins and the type of intromittant organ furthermore place the new genus in the subfamily Bythitinae.
Content may be subject to copyright.
143
The Beagle, Records of the Museums and Art Galleries of the Northern Territory, 2011 27: x–x
A new genus and species of Bythitidae (Teleostei: Ophidiiformes) from
northwestern Australia
JØRGEN G. NIELSEN1 and WERNER SCHWARZHANS2
1Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen Ø,
DENMARK
jgnielsen@snm.ku.dk
2Ahrensburger Weg 103 D, 22359 Hamburg, GERMANY
wwschwarz@aol.com
ABSTRACT
A new genus and species of bathyal bythitid sh (Teleostei: Ophidiiformes) is described based on a single specimen
caught at a depth of 392 m in the Timor Sea off the coast of northwestern Australia. Timorichthys disjunctus gen. nov.,
sp. nov. differs from all other bythitid genera by the position of the anus midway between the tip of the snout and
origin of the anal n. The joined vertical ns and the type of intromittant organ furthermore place the new genus in
the subfamily Bythitinae.
Keywords: Bythitidae, Timorichthys disjunctus gen. nov., sp. nov., viviparous brotula, taxonomy, northwestern Australia.
INTRODUCTION
The intensive bottom trawling off northwestern Australia
by the Research Vessel Southern Surveyor in 2007 revealed
a number of new and rare ophidiiform shes (Nielsen 2010,
2011). The present paper deals with one 39 mm SL adult
male trawled at a depth of 392 m. At rst it did not seem
similar to any family known from the area. However, the
ratio of the number of dorsal and anal pterygiophores to
the number of adjacent vertebrae being more than one,
the joined vertical ns, the single pelvic n ray and the
presence of a copulatory organ being an integrated part of
the eshy genital hood with the penis present as a small soft
papilla without pseudoclaspers place the specimen in the
subfamily Bythitinae of the viviparous family Bythitidae,
order Ophidiiformes (Nielsen et al. 1999).
The specimen is distinctly different from any of the 15
genera presently referred to the Bythitinae rst and foremost
by the position of the anus midway between the snout and
the anal n origin, but also by the non-tapering body, the
opercular spine being covered by skin and the head pore
pattern. Consequently, a new genus and species are here
described for it.
MATERIAL AND METHODS
The specimen is curated in Museum Victoria (NMV),
according to the standards for museum collections
Fricke & Eschmeyer (2011). Ichthyological terminology,
measurements and counts follow Nielsen et al. (1999);
the terminology of the head pores and otoliths follows
Schwarzhans et al. (2005).
SYSTEMATICS
Timorichthys gen. nov.
Type species, here designated, Timorichthys disjunctus
sp. nov. Gender masculine.
Diagnosis. Differing from all other bythitid genera by
position of anus halfway between tip of snout and origin
of anal n. Body non-tapering and compressed. Head short
with blunt snout. Scales and lateral line absent. Vertical
ns joined. Pectoral radials not prolonged. Mouth oblique,
ending well behind eye. Weak opercular spine covered by
skin. Anterior nostril close to upper lip, ending in distinct
tube. Palatines with few, small teeth. Few, large head pores:
3 anterior infraorbital pores, a pair of anterior mandibular
pores at lower jaw symphysis and 1 posterior mandibular
pore behind termination of maxilla. Otolith with small,
undivided, centrally placed sulcus. Rays in dorsal n 74,
anal n 46, pectoral n 11 or 12. Vertebrae 16+36. Anterior
gill arch with 6 long rakers.
Remarks. The combination of the position of the anus,
the hidden opercular spine, the head pores, and the form of
the body is so unique that Timorichthys does not resemble
any other bythitid genus.
Etymology. The generic name refers to the Timor Sea,
from which the holotype originated.
144
J. G. Nielsen and W. Schwarzhans
Timorichthys disjunctus sp. nov.
(Figs 1–3)
Material examined. Holotype NMV A29734-002,
39 mm SL, male, eastern Indian Ocean, Timor Sea, off
northwestern Australia, approx. 78 km south of Cartier
Island, Kulumburu L29 transect, 13°13’29’’S, 123°23’44’E
to 13°13’20’’S, 123°23’17’’E, R.V. Southern Surveyor,
Sherman sled, 392 m, 5 July 2007.
Diagnosis. See generic diagnosis above.
Description (Figs 1–3).
Meristic characters. Rays in dorsal n 74, caudal n 11-
12, anal n 46, pectoral n 11 or 12, pelvic n 1.Vertebrae
16+36= 52. Pseudobranchial laments 2. Anterior gill arch
with 6 long rakers. Origin of dorsal n above vertebra no.
9, origin of anal n below vertebra no. 24 and dorsal n ray
no. 28. Anus placed below dorsal n ray no 3.
Morphometric characters (in % SL). Head 18.5, depth
at origin of anal n 9.7, depth at origin of dorsal n 11.0,
upper jaw 7.7, depth of posterior maxilla 2.3, orbit 1.3, eye
ball 0.6, interorbital 3.8, snout 3.6, postorbital 13.5, preanal
Fig. 1. Timorichthys disjunctus Holotype, NMV A29734-002, 39 mm SL. Photograph: Markus Krag.
Fig. 2. Timorichthys disjunctus Holotype: A, Ventral view of sh; B, lateral view of head; C, dorsal view of head; D, ventral view of head;
E, lateral view of male copulatory organ; F, ventral view of male copulatory organ.
145
New genus and species of bathyal Bythitidae
52, anus to origin of anal n 26.5, predorsal 24.5, base of
pelvic ns to origin of anal n 37.0.
Head and body naked. Body non-tapering and
compressed (Fig. 1). No lateral line. Head high with blunt
snout. Vertical ns joined. Dorsal n origin above anterior
half of pectoral n. Anal n origin near midpoint of sh.
Pectoral n below midline of sh with peduncle almost as
broad as long. Pelvic ns below opercle, almost reaching
anus. Anus midway between snout and origin of anal n
(Fig. 2 A). Mouth oblique with upper jaw ending well behind
eye. Posterior end of maxilla vertically expanded. Snout
twice as long as eye diameter. Anterior nostril close to upper
lip ending in a tube; posterior nostril a mere hole close to eye
(Fig. 2 B). Opercular spine weak and covered by skin. No
spine on preopercle. Anterior gill arch with 2 small knobs on
upper branch, 1 long raker in angle and lower branch with 5
long rakers followed by 8 small knobs. All knobs and long
rakers with small, densely placed spines. Long rakers almost
twice as long as gill laments; 2 pseudobranchial laments.
Axial skeleton (from radiographs). Number of precaudal
vertebrae 16. Anterior neural spine one-third length of
second spine. All neural and haemal spines with pointed
tips. Neural spines 2–10 decreasing in length and no. 11–16
slightly increasing in length. Precaudal vertebrae 3–8 with
depressed tips, no. 4–16 with enlarged basal parts and no.
7–16 with rather short neural spine. Parapophyses developed
on vertebrae 7–16. Pleural ribs observed on vertebrae 3–7.
Epipleural ribs not observed, but they may be too thin to
show up on radiographs.
Dentition. Palatines with very few and small teeth in
1 row. Vomer boomerang formed with few, small teeth
in 1 row. Premaxilla with 2 or 3 rows of small teeth near
symphysis, decreasing to one row posteriorad. Dentary with
3 or 4 rows of small teeth near symphysis, decreasing to 1
row posteriorad.
Head pores (Fig. 2 B–D). Three anterior infraorbital
pores forming dense pattern close to upper lip in front of eye;
infraorbital pores large, about size of posterior nostril. One
anterior mandibular pore at tip of lower jaw corresponding to
rst anterior mandibular pore in terminology of Schwarzhans
et al. (2005); anterior mandibular pore large, with papilla
at anterior rim. One moderately large posterior mandibular
pore behind termination of maxilla corresponding to third
posterior mandibular pore in terminology of Schwarzhans
et al. (2005).
Otolith (Fig. 3 A–C). Small, elongate, with length to
height ratio of 2.0 and height to thickness ratio of 1.8.
Anterior and posterior tips nearly symmetrical, pointed,
slightly shifted dorsally. Dorsal and ventral rims gently
curved without prominent angles. Inner face nearly at
with central, small, oval, undivided sulcus with single
shallow colliculum. Otolith length to colliculum length =
3.5; colliculum length to height = 2.2. Dorsal depression and
ventral furrow feeble. Outer face distinctly convex, smooth.
Male copulatory organ (Fig. 2 E–F). Large, broad hood
with free, small genital papilla inserted in proximal, ventral
position.
Colour. Head and body brown with numerous, tiny, black
spots most dense on snout, cheek and jaws. Eye bluish with
greenish lens.
Biology. Viviparous species, living near to, or on, the
bottom on the deep northwestern Australian Plateau.
Distribution. Only known from the holotype trawled at
392 m off northwestern Australia.
Etymology. From disjunctus (Latin) = separated, distant,
referring to the position of the anus midway between the
tip of the snout and the origin of the anal n. The name is
adjectival.
Fig. 3. Timorichthys disjunctus Holotype, right otolith:. A, median view; B, ventral view; C, frontal view.
146
J. G. Nielsen and W. Schwarzhans
ACKNOWLEDGEMENTS
We are grateful to Martin Gomon and Dianne Bray
(NMV) who let us borrow this interesting sh. Ronald
Fricke (SMNS) is thanked for his careful review of the
manuscript.
REFERENCES
Fricke, R. & Eschmeyer, W.N. 2011. A guide to sh collections in
the Catalog of shes. Online version, updated 14 July 2011.
Internet publication, San Francisco (California Academy
of Sciences). http://research.calacademy.org/research/
Ichthyology/Catalog/collections.asp
Nielsen, J.G. 2010. Revision of the bathyal sh genus Benthocometes
(Teleostei: Ophidiidae) with a new species from off NW
Australia. Zootaxa 2561: 59–68.
Nielsen, J.G. 2011. Revision of the bathyal sh genus Pseudonus
(Teleostei, Bythitidae); P. squamiceps a senior synonym of P.
platycephalus, new to Australian waters. Zootaxa 2867: 59–66.
Nielsen, J.G., Cohen, D.M., Markle, D.F. & Robins, C.R. 1999.
Ophidiiform shes of the world (Order Ophidiiformes). FAO
species catalogue, Volume 18. FAO Fisheries Synopsis 125, v.
18: I–XI + 1–178.
Schwarzhans, W., Møller, P.R. & Nielsen, J.G. 2005. Review of the
Dinematichthyini (Teleostei: Bythitidae) of the Indo-west
Pacic. Part I. Diancistrus and two new genera with 26 new
species. The Beagle. Records of the Museums and Art Galleries
of the Northern Territory 21: 73–163.
Accepted 20 October 2011
... 50 recognized bythitid genera, namely Timorichthys Nielsen and Schwarzhans 2011. The genus belongs to the subfamily Bythitinae characterized by having the jointed vertical fins (Nielsen and Schwarzhans 2011). The present specimen differs in so many characters from the only other described species Timorichthys disjunctus Nielsen and Schwarzhans 2011 that we here describe it as a new species. ...
Article
A new bythitid fish, Timorichthys angustus, is described on the basis of a single specimen (52 mm in standard length, SL) collected from the East China Sea, Japan. The genus Timorichthys Nielsen and Schwarzhans 2011 was only known from the holotype of the type species Timorichthys disjunctus Nielsen and Schwarzhans 2011 caught in the Timor Sea. The new species differs from T. disjunctus in several characters, such as the pectoral fin peduncle being much longer than its width (vs. equal in T. disjunctus), precaudal vertebrae 22 (vs. 16), total vertebrae 62 (vs. 52), long rakers on the first gill arch 14 (vs. 6), horizontal eye diameter 3.1 % SL (vs. 1.3 % SL), interorbital width 0.8 % SL (vs. 3.3 % SL), posterior mandibular pore absent (vs. present), anterior infraorbital pores 1 (vs. 3), opercular spine not covered by skin (vs. covered by skin), otolith height to thickness 2.5 (vs. 1.8), and head and body light brown in alcohol (vs. dark brown).
Article
Full-text available
Cusk-eels of the order Ophidiiformes are a morphologically diverse assemblage of eel-like, elongate, posteriorly tapering percomorph fishes that occur worldwide in marine waters, from tropical reef areas to the deep sea. The about 400 extant and fossil species included in the ophidiiform clade are arranged into two main lineages, Bythitoidei and Ophidioidei, based on reproductive biology and the position of the anterior nostrils. The anatomy and phylogenetic relationships of these fishes are largely unknown, and the fossil record has not provided substantial information about the earliest phases of their evolutionary history. †Pastorius methenyi, new genus and species, the oldest member of the Ophidiiformes based on articulated skeletal remains, is described herein based on a single specimen collected from the Campanian-Maastrichtian organic-rich laminated limestone of the Liburnica Formation outcropping near the village of Trebiciano, north-eastern Italy. The comparative analysis of osteological and meristic features indicates that †Pastorius methenyi is characterized by at least one of the probable ophidiiform synapomorphies (exclusion of the supraoccipital from the posterior cranial margin by substantial posterodorsal extension of the exoccipitals) and exhibits a unique combination of characters, including a posteriorly broadly expanded maxilla; supramaxilla present; eight branchiostegals; 39 vertebrae; first neural spine shorter than those following; neural arch of first vertebra feebly connected to the first vertebral centrum though a narrow pedestal of bone; anterior abdominal vertebrae ostensibly lacking expanded ribs; caudal skeleton with ostensibly fused first preural, first ural centrum, first uroneural, and ventral hypural plate, and ostensibly fused second ural centrum and dorsal hypural plate, autogenous parhypural, and two epurals; caudal fin free, with 13 rays; a single ossified supraneural located in front of the second neural spine; and notably reduced number of dorsal- and anal-fin rays. †Pastorius is placed as the sister-group of all recent bythitoids, even if some features might indicate that it represents the sister-group of all ophidiiforms. †Pastorius provides the first unequivocal evidence that percomorphs with very elongate and compressed bodies were in existence in the Cretaceous, indicating that this group was characterized by a very high disparity and a vast diversification of bodyplans well before the Cretaceous-Paleogene extinction. © 2015 by the American Society of Ichthyologists and Herpetologists.
Article
Full-text available
Material of three similar and probably related genera of the viviparous ophidiiform family, Bythitidae, has been studied. The monotypic Hastatobythites is only known from the original two specimens; re-examination of the paratype and information of the holotype clearly demonstrates the validity of the genus. The revision of Saccogaster (Cohen & Nielsen 1972) was based on 15 specimens. Since then 29 additional specimens have been collected representing 11 species, three of which are here described: S. brayae, horrida and nikoliviae. Three of the 11 Saccogaster species, S. melanomycter, S. normae and S. rhamphidognatha, differ so much from the remaining eight that a new genus, Parasaccogaster, is described. The main diagnostic characters used for the three genera are: A pair of spines on frontal plate behind eyes, spines on snout, length of gill filaments on anterior arch, number and length of developed gill rakers, size of gill opening, thickness of skin, head pores, otolith morphology, color marks on head, neuromasts on head and head morphometrics, fin ray counts.
Article
Full-text available
An ongoing revision of the dinematichthyine fishes (Ophidiiformes, Bythitidae, Brosmophycinae) of the Indo-West Pacific based on ca. 5000 specimens will be published in parts. Part I includes 765 identified specimens in the genera Brotulinella (new genus with one new species), Diancistrus Ogilby, 1899 (with four described and 23 new species) and Paradiancistrus (new genus with two new species). The main distinguishing character in this group of presumably related genera is the male pseudoclasper pattern. Brotulinella is further characterized by the slender form and the generally higher number of precaudal vertebrae (12 versus 11 in the two other genera, except for one species with 12 in Diancistrus). Paradiancistrus is unique amongst Indo-West Pacific dinematichthyine genera in having only one instead of three lower preopercular pores. Brotulina Fowler, 1946, Calcarbrotula Fowler, 1946 and Parabrosmolus Machida, 1996, are regarded as junior synonyms of Diancistrus. The separating characters of the species are male pseudoclaspers, head squamation, head pores, otoliths, morphometric proportions, and fin ray and vertebral counts. Diancistrus, which has remained monotypic for more than 100 years, is here shown to be one of the most diverse genera of tropical reef fishes. The many unrecognised species have previously been confused with other genera such as Dinematichthys and Ogilbia. Pseudoclasper morphology is used to define three informal species groups in the genus Diancistrus.
Article
The bathyal genus Benthocometes (Teleostei: Ophidiidae) is revised based on 29 specimens from the Atlantic Ocean and the Mediterranean Sea and one from off NW Australia. Examination of the Atlantic and Mediterranean material confirmed the synonomizing of the three Atlantic species, B. robustus, B. armatum and B. muraenolepis. The Australian specimen represents a new species, B. australiensis, differing from B. robustus in e.g. the number of long rakers on the anterior gill arch, the form of the palatine dentition and the predorsal and upper jaw lengths.
Article
The viviparous, bathyal fish genus Pseudonus (Teleostei, Bythitidae, Bythitinae) is known from the Indo-Pacific Ocean. Three species have been described, all based on 1-2 specimens: P. acutus Garman, 1899 from the tropical East Pacific, P. platycephalus (Smith & Radcliffe, 1913) from the Indo-Australian area and P. squamiceps (Lloyd, 1907) from the Gulf of Aden. An additional 18 specimens have become available to justify this revision. The result has established the conspecificity of P. squamiceps and P. platycephalus with P. squamiceps the senior synomym of the two. The major differences between P. acutus and P. squamiceps are that the former has more dorsal (101-119 vs 95-102) and anal (74-85 vs 64-71) fin rays, more vertebrae (61-63 vs 55-58) and lacking pelvic fin rays (vs one of 15 specimens lacks pelvic fin rays). This is the first record of P. squamiceps from Australian waters.
A guide to fish collections in the Catalog of fishes Online version, updated 14 – Internet publication http://research.calacademy.org/research/ Ichthyology/Catalog/collections Revision of the bathyal fish genus Benthocometes (Teleostei: Ophidiidae) with a new species from off NW Australia
  • R Fricke
  • W N Eschmeyer
Fricke, R. & Eschmeyer, W.N. 2011. A guide to fish collections in the Catalog of fishes. Online version, updated 14 July 2011. – Internet publication, San Francisco (California Academy of Sciences). http://research.calacademy.org/research/ Ichthyology/Catalog/collections.asp Nielsen, J.G. 2010. Revision of the bathyal fish genus Benthocometes (Teleostei: Ophidiidae) with a new species from off NW Australia. Zootaxa 2561: 59–68.