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Two new species of freshwater gudgeons (Eleotridae: Mogurnda) from the Arguni Bay Region of West Papua, Indonesia.

Abstract

Two new species of Mogurnda are described from the Ar-guni Bay region of West Papua, Indonesia. Mogurnda arguni, new species is described from 80 specimens, 17.5-92.1 mm SL, collected from a small tributary of the Togarni River in the northeastern reaches of the Arguni Bay drainage. It is most similar to M magna from the Triton Lakes (lying about 80 km southeast) and M mbuta, from the Etna Bay region (about 120 km southeast). The main differences consist of a smaller head, longer pelvic fins, longer caudal fin, fewer predorsal scales and a much smaller size in M arguni in comparison with M magna. Most of these differences are also shared with M mbuta, which exhibits pronounced modal differences in number of pectoral-fin rays (78% with 16 rays vs. 48% in M arguni) and slightly higher number of rakers on the lower limb of the first gill arch. Mogurnda kaimana, new species is described from 38 specimens, 11.5110.2 mm SL, collected from Lake Furnusu, a small mountain lake 15 km northeast of Kaimana. It is most similar to M pardalis from the Triton Lakes but differs in lateral and predorsal scale counts, body depth, head length, interorbital width, pelvic-fin length, and caudal-peduncle length. In addition, preserved specimens of M kaimana are uniformly dark compared to the lighter mottled pattern of M pardalis.

Zusammenfassung

Beschrieben werden zwei neue Arten der Gundelgattung Mogurnda aus der Gegend der Arguni-Bucht in West-Papua, Indonesien. Die neue Art Mogurnda arguni wird anhand von 80 Exemplaren von 17,5-92,1 mm SL beschrieben, die in einem kleinen Nebenfluss des Togarni im Stromgebiet am nordostlichen Rand der Argunibucht gefangen wurden. Sie Ihnelt sehr stark M. magna vom Triton-Seengebiet (etwa 80 km sticlostlich) und M mbuta aus der Gegend der Etna-Bucht (etwa 120 km siidostlich). Hauptunterschei-dungsmerkmale sind der Icleinere Kopf, die langeren Bauch-flossen, eine langere Schwanzflosse, eine geringere Zahl an pradorsalen Schuppen (vor dem Riickenbeginn) und eine viel geringere Gesamtgroge. Die meisten dieser Unter- scheidungsmerkmale gelten auch fur M. mbuta; diese Art wiederum unterscheidet sich deutlich durch die Modalwerte: Zahl der Brustflossenstrahlen (78 % mit 16 Flossenstrahlen im Vergleich zu 48 % bei M arguni) und eine leicht hohere Zahl an Kiemenreusen am unteren Teil des ersten Kie-menbogens. Die neue Art Mogurnda kaimana wird besch-rieben anhand von 38 Exemplaren mit 11,5-110,2 mm SL, gesammelt im Lake Furnusu, einem kleinen Bergsee 15 km nordostlich von Kaimana. Diese ahnelt stark M. pardalif von den Triton Lakes, unterscheidet sich aber durch die Zahlen der seitlichen und pradorsalen Schuppen, Korpertiefe, Kopf-lange, interorbitale Breite (zwischen den Augen), Bauch-flossenlange und Schwanzstiellange. Konservierte Exemplare von M kaimana sind au8erdem einheitlich dunkel im Ge-gensatz zu dem hellen Fleckenmuster bei M pardalis.

Resume

Deux nouvelles especes de Mogurnda sont decrites prove-nant de la region d'Arguni Bay en West Papua, Indonesie. Mogurnda arguni, nouvelle espece, est decrit sur base de 80 specimens, 17,5-92,1 mm de LS, collectes dans un petit tri-butaire de la Togarni River, dans les &endues nord-est du systeme de l'Arguni Bay. II s'apparente le plus a M magna des Triton Lakes (a environ 80 km au sud-est) et a M mbu-ta, de la region d'Etna Bay (a environ 120 km au sud-est). Les differencesAprincipales concernent une tete plus petite, de plus longues pelviennes, une caudale plus longue, moms d'ecailles predorsales et une taille bien inferieure pour M ar-guni compare a M. magna. La plupart des differences sont partagees avec M. mbuta qui montre des differences mod-ales prononcees par rapport aux rayons de la pectorale (78% avec 16 rayons contre 48% pour M arguni) et un nombre legerement superieur de branchiospines sur le limbe infe-rieur du premier arc branchial. Mogurnda kaimana, nouvelle espece, est decrit sur base de 38 specimens, 11,5 110,2 mm de LS, collectes dans le lac Furnusu, un petit lac de montagne a 15 km au nord-est de Kaimana. II s'apparente le plus a M pardalis des Triton Lakes, mais se distingue par le nom-bre d'ecailles laterales et preclorsales, la hauteur du corps, la longueur de la tete, l'espace interorbital, la longueur de la pelvienne et celle du pedoncule caudal. En outre, les specimens conserves de M kaimana sont uniformement sombres compares au patron plus clair et mouchete de M pardalis.

Sommario

Due nuove specie di Mogurnda sono descritte dalla regione Arguni Bay di West Papua, Indonesia. Mogurnda arguni, nuova specie, e descritta sulla base di 80 esemplari di 17,592,1 mm SL, raccolti in un piccolo affluente del flume To-garni nel tratto nord-orientale del bacino idrogeografico di Arguni Bay. Presenza somiglianze con M magna descritta dai laghi Triton (che si trovano a circa 80 km a sud-est) e M mbuta dalla regione Etna Bay (circa 120 km a sud-est). Le differenze principali tra M arguni e M magna consistono in una testa piu piccola, pinne pelviche piu lunghe, pinna cau-dale pii lunga, un minor numero di squame predorsali e di-mensioni complessive molto piu ridotte. La maggior parte di queste differenze sono anche condivise nel confronto con M mbuta, che presenta marcate differenze modali nel nu-mero di raggi della pinna pettorale (78% con 16 raggi con-tro 48% in M arguni) e un numero leggermente maggiore di rastrelli sul lembo inferiore del primo arco branchiale. Mogurnda kaimana, nuova specie, e descritta da 38 esem-plari di 11,5-110,2 mm SL, raccolti dal Lago Furnusu, un piccolo lago di montagna 15 km a nord-est di Kaimana. piii simile a M pardalis dai laghi Triton ma differisce nel conteggio delle scaglie laterali e predorsali, nell'altezza del corpo, la lunghezza della testa, l'ampiezza interorbitale, la lunghezza della pinna pelvica e la lunghezza del peduncolo caudale. Inoltre, gli esemplari conservati di M kaimana sono uniformemente scuri rispetto alla livrea leggermente chiazzata di M. pardalis.

INTRODUCTION

The eleotrid genus Mogurnda Gill 1863 is common in fresh waters of Australia and New Guinea. The group contains at least 27 species, including two new taxa described herein. Allen and Jenkins (1999) reviewed the six Australian members of the genus including M mogurnda (Richardson 1844) and M adspersa (Castelnau 1878), which range widely in the north and east respectively, M oligolepis Allen & Jenkins 1999 from the Kimberley region, and three species from central Australia: M larapintae (Zietz 1896), M clivicola Allen & Jenkins 1999, and M thermophila Allen & Jenkins 1999. Mogurnda mogurnda also occurs at the Aru Islands (Indonesia) and in the Trans-Fly region of western Papua New Guinea. The remaining 21 species (Table I) inhabit the New Guinea mainland. Twelve species are confined to various lakes, mainly Lake Kutubu (seven species; Allen & Hoese 1986 and Jenkins et al. 2000) at the headwaters of the Kikori River in central Papua New Guinea, and lakes of the Birds Neck region (five species; Allen & Renyaan 1996 and Allen & Jenkins 1999) of Indonesian Papua (Fig. 1). Considering the highly restricted range of many of the described species, additional new taxa will certainly be discovered, particularly at previously uncollected remote locations.

Table I. List of Mogurnda species from the island of New Guinea.

Species                            Distribution

Mogurnda aiwasoensis Allen &c      Triton Lakes, West Papua
Renyaan 1996

Mogurnda arguni Allen & Hadiaty    Arguni Bay drainages, W. Papua
2014

Mogurnda aurifodinae Whitley       Widespread northern New Guinea
1938

Mogurnda cingulata Allen &t Hoese  Fly River, PNG to Timika, W.
1991                               Papua

Mogurnda Jurva Allen & Hoese       Lake Kutubu, Papua New Guinea
1986

Mogurnda kaifayama Allen &         Lake Kaifayama, Etna Bay, West
Jenkins 1999                       Papua

Mogurnda kaimana Ahen & Hadiary    Lake Furnusu, Kaimana district,
2014                               W. Papua

Mogurnda kutubuensis Allen &       Lake Kutubu, Papua New Guinea
Hoese 1986

Mogurnda UneataMien &c Hoese       Kokoda vicinity, E. Papua New
1991                               Guinea

Mogurnda maccuneae Jenkins,        Lake Kutubu, Papua New Guinea
Buston &i Allen 2000

Mogurnda magna Allen & Renyaan     Triton Lakes, West Papua
1996

Mogurnda malsmithi Allen & jebb    Purari River system, Papua New
1993                               Guinea

Mogurnda mbutaMlen & Jenkins       Mbuta Basin, Etna Bay, West
1999                               Papua

Mogurnda mogurnda (Richardson      Trans-Fly region and Aru Islands
1844)

Mogurnda mosa Jenkins, Buston &    Lake Kutubu, Papua New Guinea
Allen 2000

Mogurnda orientals Allen &C Hoese  Musa River system, E. Papua New
1991                               Guinea

Mogurnda pardalis Allen & Renyaan  Triton Lakes, West Papua
1996

Mogurnda pulchra Horsthemke &      E. Gulf of Papua drainages, PNG
Staeck 1990

Mogurnda spilota Allen & Hoese     Lake Kutubu, Papua New Guinea
1986

Mogurnda variegata Nichols 1951    Lake Kutubu, Papua New Guinea

Mogurnda vitta Allen & Hoese       Lake Kutubu, Papua New Guinea
1986

Mogurnda wapoga Allen, Jenkins &   Wapoga River System, West Papua
Renyaan 1999


The present paper describes two new species collected during a freshwater fish survey of the Arguni Bay region of West Papua, Indonesia in November 2010. The new discoveries represent the westernmost records for the genus in New Guinea, which occurs throughout most of the main landmass of this island and the nearby Aru Islands at elevations below about 600 m. However, it is thus far unknown from the Birds Head Peninsula (Fig. 1), which apparently represents a detached piece of the Australian continental craton that collided with New Guinea during the Miocene (Polhemus 2007). Mogurnda and the atherinid genus Craterocephalus, which frequently co-occur elsewhere, are conspicuously missing from the Birds Head fish community, which is otherwise comprised of typical New Guinean components such as Neosilurus Stein-dachner, 1867 (Plotosidae), Melanotaenia Gill, 1862 (Melanotaeniidae), Pseudomugil Kner, 1866 (Pseudomugilidae), Hephaestus De Vis 1884 (Terapontidae), Glossogobius Gill 1859 (Gobiidae), and Oxyeleotris Bleeker 1874 (Eleotridae).

Mogurnda occur in a variety of fluvial and lacus-trine habitats. They exhibit a particular preference for small, relatively slow to moderate-flowing rainforest creeks, well-vegetated ponds or floodplain lakes, swamps, and karst springs and lakes in hilly terrain. They are typically found alone or in small loose groups, either resting on the bottom or hovering in midwater a short distance above the substrate. Stomach contents of M aurofodinae from the Sepik River system indicate a diet of mainly aquatic and terrestrial insects (Allen & Coates 1990). Relatively large (about 3 mm long), elliptical eggs are deposited on rocky surfaces and guarded by the male. The incubation period is about six days (Allen & Coates 1990). Most species grow to about 80-110 mm SL, but lacustrine species frequently attain a maximum SL of 110-140 mm SL. The largest species by far is M magna from the Triton Lakes of West Papua, which is known to reach at least 191 mm SL (Allen & Renyaan 1996).

MATERIALS AND METHODS

The methods of counting and measuring are as follows: dorsal and anal rays--the last ray of the anal and second dorsal fins is divided at the base and counted as a single ray; gill raker count--number of gill rakers on the first branchial arch. This count is given in two parts (upper and lower limb). The raker at the angle of the gill arch is included in the lower limb count; lateral scale count--number of scales from upper pectoral base to caudal-fin base, excluding the small scales posterior to the hy-pural junction; transverse scale rows--number of scales from anal spine obliquely upward and backward to second dorsal-fin base; predorsal scales--number of scales along midline of nape in front of first dorsal fin; standard length (SL)--measured from the tip of the upper lip to the caudal-fin base; head length--measured from the tip of the upper lip to the upper rear edge of the gill opening; caudal peduncle depth is the least depth and caudal peduncle length is measured between two vertical lines, one passing through the base of the last anal ray and the other through the caudal-fin base.

Counts and measurements that appear in parentheses in the new species descriptions refer to the range for paratypes. Type specimens are deposited at the Museum Zoologicum Bogoriense, Bogor, Indonesia (MZB) and the Western Australian Museum, Perth (WAM).

Mogurnda arguni n. sp. (Figs 2-3, Tables II-III)

Table II. Frequency distribution of counts for pectoral-fin rays,
lateral scales

Pectoral rays                              Predorsal scales

Species     15  16  17      17  18  19  20  21  22  23  24  25  26  27

M. arguni   20  22           2   9  20   7   3   1

M. kaimana   8  14   2                   4  10   3   4   2

M. magna     2  14   2               1   3   8   3   1   1

M. mbuta     6  20   1       1   3   6   6   1

M.           1   2
partialis

Scales in lateral series

Species     35  36  37  38  39  40  41  42  43  44  45  46  47  48  49

M. arguni        5   7  10  16   4

M. kaimana       2   6   8   3   2   2   1

M. magna         I   2   6   3   2   2   1

M. mbuta     2   4   2   4

M.                                       1       1           1
pardalis

Scales in transverse series

Species     12  13  14  15  16  17

M. arguni           26  17

M. kaimana           6  16   2

M. magna         6  10   2

M. mbuta     5   7

M.                       2   1
pardalis

Table III. Comparison of maximum size, predorsal scales,
pelvic-fin length and caudal-fin length of Mogurnda
arguni, M. magna, and M. mbuta. *Note following
percentages for lower-limb gill raker counts: M arguni
(88% with 8-9), M magna (60% with 8-9), and M mbuta
(100% with 10-11).

Character     M. arguni   M. magna      M. mbuta

Maximum SL    92.1        191.0         101.5

Predorsal     17-21       21-26         18-22
scales

Lower-limb    Usually 9   Usually 9-10  Usually
gill rakers*                            10-11

Pelvic-fin    21.0-24.2%  19.4-21.5%    17.4-24.4%
length        SL          SL            SL

Caudal-fin    26.5-29.1%  21.0-26.5%    27.1-29.9%
length        SL          SL            SL


Holotype: MZB 22091, female, 92.1 mm SL, Wahisewar stream, 03[degrees]03.920'S, 133[degrees]58.309'E, tributary of Togarni River, West Papua, Indonesia; rotenone, R. Hadiaty and party, 2 November 2010 Paratypes: MZB 19615, 74 specimens, 17.5-66.2 mm SL, collected with holotype; WAM P.33336001, 5 specimens, 36.2-104.0 mm SL, collected with holotype.

Diagnosis: A species of Mogurnda with the following combination of characters: soft dorsal rays 11 or 12; soft anal rays 10-13 (rarely 10 or 13); pectoral rays 15-16; scales in lateral series 36-40; predorsal scales 17-22; lower limb gill rakers usually 9; snout profile straight to slightly convex; pelvic-fin length 21.0-24.2% SL; caudal-fin length 26.5-29.1% SL; young specimens with series of 10 dark bars on side; adults generally darker with less vivid bars; maximum size to at least 92.1 mm SL.

Description: Dorsal rays VIII-I,12 (11-12); anal rays 1,13 (11-12, except one with 10); pectoral rays 16 (15-16); segmented and branched caudal rays 15 (usually 15, except two with 14); scales in lateral series 39 (36-40); transverse scale rows 14 (14-15); predorsal scales 20 (17-22); circurnpeduncular scales 21 (20-24); postdorsal scales 12 (10-12); gill rakers on first arch 2 + 9 (1-3 + 8-10); total rakers 11(10-12).

Body elongate, laterally compressed, more strongly posteriorly; body depth at pelvic fin origin 26.8 (24.4-27.5) percent of SL; body depth at anal fin origin 26.2 (20.9-26.6) percent of SL. Head rounded its profile straight or slightly convex; nape strongly arched. Head length 33.7 (32.5-35.6), snout length 10.5 (8.5-11.0), eye diameter 6.8 (6.92-8.2), interorbital width 11.7 (9.5-12.7), all as percentage of SL.

Lower jaw protruding slightly, mouth of holotype forming an angle of about 32 degrees with longitudinal axis of body; jaw extending to level of anterior edge of pupil; teeth of jaws numerous, in dense bands, outer row enlarged; palate edentulous; tongue, palate and floor of mouth generally pale with faint melanophores. Gill opening extends slightly forward of posterior margin of preopercle.

Scales of head, predorsal region, breast, belly, uppermost part of back and bases of caudal and pectoral fins cycloid, remainder of body scales ctenoid. Head entirely scaled except lips, snout tip, preorbital region, lower jaw and chin; preopercle scales smaller than body scales and tend to be embedded; sensory pores absent on head, but tracks of well-developed papillae arranged as shown in Fig. 3.

First dorsal fin slightly shorter than second dorsal in adults and juveniles; depressed posterior rays of first dorsal fin extending slightly beyond origin of second dorsal fin in adults and about even with or just falling short of origin in specimens less than about 60 mm SL; depressed posterior rays of second dorsal fin extending about three-fourths length of caudal peduncle in large adults, but usually only half length of peduncle or less in smaller specimens; penultimate anal ray tallest, 16.4 (12.5-16.5) percent of SL; sixth or seventh spine of first dorsal fin tallest, 13.3 (9.7-13.3) percent of SL; last 2-3 rays of second dorsal fin tallest, 18.5 (10.219.3) percent of SL; pectoral-fin length 21.0 (22.424.8) percent of SL; pelvic-fin length 21.0 (21.5- 24.2) percent of SL; depressed pelvic-fin tips falling slightly short of anus, except reaching anus in specimens less than about 40 mm SL. Caudal peduncle relatively elongate, its length 20.1 (20.625.5) percent of SL, and depth 14.8 (10.3-15.6) percent of SL. Caudal-fin rounded, its length 28.7 (25.9-29.1) percent of SL.

Colour in li fe (from field notes): Juveniles (< about 50 mm SL) generally purplish-grey brown, darker on back, often with irregular dark brown mottling; about 10 red-brown bars, usually with bifurcate ventral extensions along middle of side, with greenish white area between bars; lower third of body including ventral parts generally white; cheek light grey to bluish with pair of oblique red-brown bands from ventral edge of eye to lower margin of operculum; similar band just above, crossing middle of operculum to pectoral fin-base; median fins generally translucent to light grey; first dorsal fin with 1-2 rows of red-brown spots on basal half; second dorsal fin with white outer edge, scattered small red-brown spots, and 3-4 large red-brown spots along base; anal and caudal fins mainly translucent or slightly dusky and lacking spots; pectoral and pelvic fins mainly translucent; middle of pectoral fin base with dark brown triangular marking with blue area immediately above and yellowish below. Two largest specimens (92.1 mm SL holotype and 75.8 mm paratype) darker overall with ground colour light purple to brownish and less contrasted dark bars on sides and bands on head.

Colour in alcohol: Young fish (less than about 60 mm SL) brown dorsally, grading to creamy yellow or tan on side and ventral portion of body; 10 relatively broad, brown bars on middle of side, becoming more distinct posteriorly; pair of oblique dark bands (often faint) with pale area between them, from ventral edge of eye to lower margin of operculum; additional dark band (often faint) crossing operculum to pectoral-fin base; median fins translucent to dusky grey with darker spotting on dorsal fins; 3-4 large dark spots along base of second dorsal fin, more evident in freshly preserved specimens; pelvic fins greyish with white outer margin; pectoral fins translucent with numerous small melanophores on fin rays; dark brown or black spot covering most of pectoral-fin base. Markings become less distinct with increased growth. Adults generally retain the distinct juvenile colour pattern, although the general ground colour is darker brown with less vividly contrasted bars and bands. The median fins of the holotype and largest paratype (75.8 mm SL) are generally dusky grey with spotting evident only on the dorsal fins.

Comparisons: Mogurnda arguni is most similar to M. magna (Fig. 4) from the Triton Lakes (lying about 80 km southeast) and M. mbuta (Fig. 5) from the Etna Bay region (about 120 km southeast). The three species are generally similar in shape, exhibiting the rounded snout profile that is typical of the majority of Mogurnda in contrast to the flattened, concave profile found in a few lacus-trine species (see Figs 9-10). Juvenile colour patterns of the three species are also similar, featuring a series of dark bars on the side of the body and oblique bands radiating posteriorly from the eye. Selected meristic features are compared in Table II and the salient differences between these species are summarised in Table III. The main differences consist of a smaller head, longer pelvic fins, longer caudal fin, fewer predorsal scales and much smaller size in M. arguni in comparison with M. magna. Most of these differences are also shared with M. mbuta, which exhibits pronounced modal differences in number of pectoral-fin rays (78% with 16 rays versus 48% in M arguni) and slightly higher number of rakers on the lower limb of the first gill arch (100% with 10-11 rakers versus 88% with 89 rakers in M. arguni). The colour patterns of the three species are also noticeably different. Although the juvenile pattern of dark bars along the side is similar, the barred patterns of M. magna and M. mbuta are gradually lost with growth, being replaced by a complex maze-like pattern of irregular spots and blotches (Figs 4-5).

Distribution and habitat: The type locality (Fig. 6) is situated near the easternmost extension of Ar-guni Bay, a large marine incursion lying between the Bomberai Peninsula to the west and main body or Birds Neck region of New Guinea to the east. The habitat consists of a small rainforest tributary of the Togarni River at an elevation of 45 m, about 13 km upstream from the mouth where it flows into Karora Estuary. The stream was relatively clear and slow-flowing with patchy aquatic vegetation. Other species present at the type locality included Melanotaenia ammeri Allen, Unmack & Hadiaty 2008 (Melanotaeniidae), Pseudomugil sp. (Pseudo-mugilidae), Glossamia arguni Hadiaty & Allen 2011 (Apogonidae) and several gobiioid fishes: Redigobius chrysosoma (Bleeker 1875), Mugilogobius mertoni (Weber 1911), Eleotris melanosoma Bleek-er, 1852, Periophthalmus weberi Eggert 1935, and Oxyeleotris nullipora Roberts 1978.

Etymology: The species is named arguni with reference to the general type locality, which encompasses the eastern side of Arguni Bay, West Papua. The name is treated as a noun in apposition.

Mogurnda kaimana n. sp. (Figs 7-9, Tables II & IV)

Table IV. Comparison of selected characters related
to scale counts and body proportions of Mogurnda
kaimana and M pardalis.

Character         M. kaimana     M. partialis

Lateral scales    36-42          42-47

Predorsal scales  21-25          28-32

Depth at pelvic   23.7-31.3% SL  19.7-23.5% SL
origin

Depth at anal     21.1-26.4% SL  17.9-21.9% SL
origin

Head length       34.3-38.1% SL  39.0-40.9% SL

Intetotbital      11.3-14.2% SL   9.0-10.3% SL
width

Pelvic-fin        18.6-25.9% SL  16.2-18.9% SL
length

Caudal-peduncle   12.4-15.2% SL   9.5-12.3% SL
depth


Holotype: MZB 19774, female, 110.2 mm SL, Lake Furnusu, 03[degrees]33.492'S, 133[degrees] 52.747' E, Bit-syara Bay district, about 15 km northeast of Kaimana, West Papua, Indonesia; seine, Sopian, 10 November 2010.

Paratypes: MZB 19658, 24 specimens, 11.5-81.9 mm SL, same location as holotype, rotenone, G. Allen & M. Ammer, 3 November 2010; MZB 19755, 8 specimens, 25.4-89.2 mm SL, collected with holotype; WAM P.33338-001, 5 specimens, 36.5-107.4 mm SL, collected with holotype.

Diagnosis: A species of Mogurnda with the following combination of characters: soft dorsal rays 11 or 12; soft anal rays 12 (rarely 11); pectoral rays 15-17, rarely 17; scales in lateral series 36-42; predorsal scales 21-25; rakers on lower limb of first gill arch usually 9 (80% of specimens with 8-9); body depth at pelvic origin 21.1-26.4% SL; body depth at anal origin 21.1-26.4% SL; head length 34.338.1% SL; interorbital width 11.3-14.2% SL; pelvic-fin length 18.6-25.9% SL; caudal-peduncle depth 12.4-15.2% SL; snout profile concave, especially noticeable in adults, but detectable in juveniles as small as 25 mm SL; young specimens with a series of about 10 dark squares on sides, gradually developing pattern of numerous irregular spots and blotches on side, becoming increasingly melanistic with age, adults entirely dark brown, nearly blackish (sometimes with hint of darker mottling); maximum size to at least 110 mm SL.

Description: Dorsal rays VIII ( one paratype with VII) + 1,11 (11-12); anal rays 1,12 (11-12); pectoral rays 16 (15-16, except one paratype with 17); branched and segmented caudal rays 15; scales in lateral series 41 (36-42); transverse scale rows 15 (14-16); predorsal scales 21(21-25); circumpedun-cular scales 23 (21-23); postdorsal scales 12 (1113); gill rakers on first arch 3+8 (2-4 + 8-10), total rakers 11(10-13).

Body elongate, laterally compressed, more strongly posteriorly; body depth at pelvic fin origin 31.3 (23.7-31.0) percent of SL; body depth at anal fin origin 26.0 (21.1-26.1) percent of SL. Head pointed when viewed laterally; snout profile concave, especially noticeable in adults, but also apparent in juveniles to at least 30 mm SL; nape strongly arched. Head length 38.1 (34.3-27.5), snout length 11.0 (8.8-11.3), eye diameter 6.1 (6.1-8.1), interorbital width 14.2 (11.3-14.0), all as percentage of SL.

Lower jaw protruding slightly, mouth of holotype forming angle of about 46 degrees with longitudinal axis of body; jaw extending to level of anterior edge of pupil or slightly posterior; teeth of jaws numerous, in dense bands, outer row enlarged and individual teeth well-separated; palate edentulous; tongue, palate and floor of mouth generally pale with pepper-like melanophores. Gill opening extends forward to about level of midway point between upper rear margin of preopercle and posterior edge of eye.

Scales of head, predorsal region, breast, belly, uppermost part of back and bases of caudal and pectoral fins cycloid, remainder of body scales ctenoid. Head entirely scaled except lips, snout tip, preorbital region, lower jaw and chin; preopercle scales smaller than body scales and tend to be embedded, especially in smaller specimens; sensory pores absent on head, but tracks of well developed papillae arranged as shown in Fig. 9.

First dorsal fin slightly shorter than second dorsal in adults and juveniles; depressed posterior rays of first dorsal fin extending slightly beyond origin of second dorsal fin in adults and about even with origin in specimens less than about 60 mm SL; depressed posterior rays of second dorsal fin extending about two thirds length of caudal peduncle in large adults, but usually only half length of peduncle or less in smaller specimens; sixth or seventh spine of first dorsal fin tallest, 10.4 (11.5-12.2) percent of SL; last 2-3 rays of second dorsal fin tallest, 14.5 (12.0-15.9) percent of SL; penultimate anal ray tallest, 14.6 (10.5-15.0) percent of SL; pectoral-fin length 22.9 (19.7-22.5) percent of SL; pelvic-fin length 21.1 (18.6-25.9) percent of SL; depressed pelvic fin tips falling well short of anus. Caudal peduncle relatively elongate, its length 18.9 (18.2-25.7) percent of SL, and depth 14.6 (12.414.8) percent of SL. Caudal-fin rounded, its length 25.2 (22.1-26.3) percent of SL.

Colour in life: Juveniles brown dorsally, grading to pale yellow on side of body with series of 10, large red-brown squares in midlateral row; pair of oblique brown bands from lower rear corner of eye to lower margin of operculum; additional brown stripe just above and parallel to previous pair, crossing opercle and joining dark brown triangular mark on pectoral-fin base; fins translucent to slightly dusky with 3 large reddish spots at base of second dorsal fin, and smaller reddish brown spots on remainder of fin and faint spotting on caudal fins; pelvic fin white and pectoral fins translucent. Intermediate individuals (approximately 40-65 mm SL, Fig. 7) darker overall with juvenile bars replaced by complex pattern of irregular spots and blotches on pale golden yellow background; oblique dark bands on the head (as described for juveniles) more intense and dark marking on pectoral-fin base particularly dark, highlighted by yellow areas dorsally and ventrally; median fins generally dusky with whitish margins; first dorsal fin with faint spotting; second dorsal fin with 3-4 large reddish spots near base; caudal fin mainly dark grey; anal fin dusky grey with yellowish basal portion surrounding 3-4 large dark blotches; pectoral and pelvic fins translucent, except individual rays frequently brown or grey.

Large specimens (> 89 mm SL) generally purplish brown with darker brown blotches, mottling, and bands (pattern similar to that shown in Fig. 7); fins dusky purplish with spotting evident on dorsal, anal, and caudal fin; pelvic fins purplish grey; pectoral fins translucent with dark grey rays.

Colour in alcohol: large specimens (in excess of about 89 mm SL, including holotype) overall dark brown on body and median fins with very faint indication of pattern shown in Fig. 7 of live individuals; dark spotting on median fins evident when specimen illuminated from behind; head dark brown dorsally, lighter brown on opercle and preopercle, grading to dusky whitish on ventral portions and adjacent breast; pair of diagonal, dark brown bands from lower edge of eye to lower margin of opercle; similar band across middle of opercle, more or less continuous with prominent dark mark on pectoral-fin base; pelvic fins dark grey; pectoral fins translucent with greyish rays.

Juvenile (less than 40 mm SL) yellowish tan to brown, grading to yellowish white or tan on ventral parts; about 10 evenly spaced, dark brown squares midlaterally on side of body, increasingly obscure with growth, particularly on anterior half; marking on caudal-fin base usually more vivid and enlarged; oblique bands on head and prominent dark marking on pectoral-fin base similar to those of large specimens described above.

Comparisons: Mogurnda kaimana is most similar to M pardalis Allen and Renyaan, 1996 (Fig. 10) from the Triton Lakes (Lake Kamaka), which lie from it by a steep ridge that rises to an altitude of about 500-550 m. The lake occupies a scenic basin that is approximately five km long and 1-2 km wide. It is completely surrounded by steep ridges without any connection to the nearby sea. Drainage appears to be subterranean, which is typical for other lakes in this region (e.g. Triton Lakes, lying 40 km to the southeast) that consists of rugged limestone karst. The current Google Earth satellite image of the lake basin reveals that it is mainly dry or swampy, but the water level at the time of our collection was extremely high and most of the basin was filled with a large continuous lake with swampy margins. Judging from snorkel observations and partially submerged trees we estimate the shoreline was approximately 3-4 in above normal levels. Most paratypes were collected adjacent to a rocky shore among aquatic vegetation and submerged Pandanus roots. Four other species were present in the lake, which are provisionally identified as Neosilurus brevidorsalis (Gunther 1867) (Plotosidae) , Craterocephalus sp. (Atherinidae) , Melanotaenia mairasi Allen & Hadiaty 2011 (Melanotaeniidae) , and Oxyeleotris nullipora Roberts 1978.

Etymology: The species is named kaimana with reference to the nearby town of Kaimana, which is the capital of Kaimana Regency, within which the type locality is situated.

ACKNOWLEDGEMENTS

We are especially indebted to Richard Sneider and Fabian Oberfeld, who provided financial sponsorship, excellent companionship, and field assistance. Special thanks are also due to the local government and the masyarakat adat (traditional communities) of Kaimana and Arguni Bay for allowing us to visit their spectacular homeland and for their commitment to preserve it. Max Ammer (Raja Ampat Research & Conservation Centre) provided his piloting expertise in an ultralight aircraft and collecting assistance during the visit to Lake Furnusu and other excursions during the expedition. We also thank our LIPI colleagues Daisy Wowor, Ristiyanti Marwoto, Mulyadi, Sopian, and Samuel Renyaan (University of Cendrawasih) for their advice and collecting assistance. Ken & Josephine Wieden- hoeft and their crew on Puti Raja were excellent hosts for the 2010 Arguni Expedition and provided essential logistic assistance. We are also indebted to Nimrod (Roy) Tafre from the Kaimana Spatial Planning Department and Zeth Parinding from the Kaimana Department of Nature Conservation for their help in making our expedition possible and for collection assistance. The staff of the Kaimana office of Conservation International (CI) was very helpful with planning issues and communication with local authorities. We also thank the Paine Family Trust and William Mathews Brooks for funding support for this taxonomic work. Last, but not least, we are most grateful to Mark Erdmann (CI) for his tireless organizational efforts and essential assistance during the Arguni Bay expedition. He also reviewed the manuscript.

REFERENCES

ALLEN, G. R. & COATES, D. 1990. An ichthyological survey of the Sepik River, Papua New Guinea. Records of the Western Australian Museum Supplement 34: 31-116.

ALLEN, G. R. 8L HOESE, D. F. 1986. The eleotrid fishes of Lake Kutubu, Papua New Guinea with descriptions of four new species. Records of the Western Australian Museum 13 (1): 79-100.

ALLEN, G. R. & HOESE, D. F. 1991. A review of the genus Mogurnda (Pisces: Eleotrididae) from New Guinea with descriptions of three new species. Ichthyological Exploration of Freshwaters 2 (1): 31-46.

ALLEN, G. R. & JENKINS, A. P. 1999. A review of the Australian freshwater gudgeons, genus Mogurnda (Eleotri-dae) with descriptions of three new species. aqua, Journal of Ichthyology and Aquatic Biology 3 (4): 141-156.

ALLEN, G. R. & JENKINS, A. P. 1999. Two new species of Mogurnda (Osteichthyes: Eleotrididae) from the Etna Bay Region, Irian Jaya, Indonesia. Ichthyological Exploration of Freshwaters 10 (3): 237-246.

ALLEN, G. R. & RENYAAN, S. J. 1996. Eleotrid fishes of the Triton Lakes, Irian Jaya, with description of four new species. Revue franfaise d'Aquariologie Herpetologie 23 (12): 47-56.

JENKINS, A. P., BUSTON, P. M. & ALLEN, G. R. 2000. Two new species of freshwater gudgeons (Eleotrididae: Mogurnda) from Lake Kutubu, Papua New Guinea. Ichthyological Exploration of Freshwaters 11(1): 47-54.

POLHEMUS, D. A. 2007. Tectonic geology of Papua. In: The Ecology of Papua. (Eds. A. J. Marshall & B. M. Beehler): 137-164. Periplus Editions, Singapore.

Gerald R. Allen' and Renny K. Hadiaty(2)

1) Western Australian Museum, Locked Bag 49, Welshpool DC, Perth, Western Australia 6986.

E-mail: tropical_reef@bigpond.com

2) Museum Zoologicurn Bogoriense (MZB), Division of Zoology. Research Centre for Biology, Indonesian Institute of Sciences (LIPI), Jalan Raya Bogor, Km 46, Cibinong 16911, Indonesia.

Received: 7 March 2014--Accepted 11 April 2014
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Author:Allen, Gerald R.; Hadiaty, Renny K.
Publication:aqua: International Journal of Ichthyology
Article Type:Report
Geographic Code:9INDO
Date:Apr 1, 2014
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