Pseudogobiopsis oligactis ( Bleeker, 1875 )

Larson, Helen K., 2009, Review Of The Gobiid Fish Genera Eugnathogobius And Pseudogobiopsis (Gobioidei: Gobiidae: Gobionellinae), With Descriptions Of Three New Species, Raffles Bulletin of Zoology 57 (1), pp. 127-181 : 157-162

Pseudogobiopsis oligactis ( Bleeker, 1875)

( Figs. 22 , 26 ; Plate 2B; Tables 13–16, 18)

Gobiopsis oligactis Bleeker, 1875: 113-114 (Amboina, Indonesia). – Koumans, 1931: 67; Bleeker, 1983: Pl. 433, Fig. 4 .

Glossogobius campbellianus Jordan & Seale, 1908: 542, Fig. 2 (Buytenzorg, Java).

? Glossogobius mas Hora, 1923: 742–743 , Fig. 23 (Chilka Lake: off Samal Island, Rambha Bay, off Barkul).

Pseudogobius neglectus Koumans, 1931: 102 (nomen nudum; Bleeker museum name). – Bleeker, 1983: Pl. 438, Fig. 13 .

Stigmatogobius neglectus Koumans, 1932: 3 , 5 (western Java).

Pseudogobiopsis oligactis – Koumans, 1935: 131–132, Fig. 4 ; Fowler, 1937: 251; Koumans, 1940: 126; Smith, 1945: 521–522; Kottelat, 1989: 19; Kottelat et al., 1993: 150, Pl.70; Lim & Larson, 1994: 260; Kottelat & Lim,1995: 247; Ng & Tan, 1999: 364; Larson & Lim, 2005: 143; Larson et al., 2008: 143.

Vaimosa perakensis Herre, 1940: 21 , Pl. 16 (Lake above Chenderoh Dam, Perak, Malay Peninsula).

Stigmatogobius oligactis – Koumans 1953: 110, 116–117, Fig. 27 ; Chatterjee, 1980: 229, 230.

Stigmatogobius poicilosoma (in part) – Alfred, 1966: 47.

Stigmatogobius isognathus - Mohsin & Ambak, 1983: 187, Fig. 141.

Mugilogobius perakensis – Kottelat, 1989: 19.

?Genus and species undet. – Roberts, 1993: 44, Fig. 51.

Pseudogobiopsis campbellianus – Kottelat et al., 1993: 150, Pl. 70 (in part).

Pseudogobiopsis neglectus – Kottelat et al., 1993: 150, Pl. 70.

Eugnathogobius oligactis – Larson, 2001: 6970.

Material Examined. – INDIA: CAS 61960, 3(15.0–20.5), sandy beach at Hampi, Tungabahdra River, Bellary District, Karnataka State, Mysore, T. Roberts, 3 Feb.1985. THAILAND: CMK 5385, 22(17–36), stream on road from Ranong to Kra Buri, Ranong Province, M. Kottelat, 24 Apr.1985; KUMF uncatalogued, 3(37.5–41.0), Tha Lad Waterfall, Samui, Surathani Province, C. Vidthayanon, 22 Jul.1983; NIFI 1230, 3(33.5–41.0), Chiew Larn Dam, Klong Saeng, Surat Thani Province, J. Karnasutra, 20 Mar.1983. CAMBODIA: CMK 4806, 1(35), Stung Tong Hong, 77 km on road from Phnom Penh to Sihanoukville, d’Aubenton, 13 Jan.1963. MALAYSIA: Holotype of Vaimosa perakensis, CAS 32975, 1(25.5), Chanderoh Dam, Perak, A.W. Herre, 9 Mar.1937. Paratypes of Vaimosa perakensis, CAS 32977, 17(13.5–28.5), 2 miles N of Sauk, Perak, A.W. Herre, 18 Apr.1937; ZRC 255, 47(12-24.8), lake above Chanderoh Dam, Perak, A. W. Herre & M. F. Tweedie, 19 Mar.1937. CMK 7422, 4(24–31), NE foothills of Gunung Panti, N of Kota Tinggi, Johore, M. Kottelat et al., 1991; NTM S.16374-001, 1(30.5), cleared and stained, same data as preceding; ZRC 19323–19325, 1 of 3(34), Desaru Road, Kota Tinggi, Johor, P. Ng & M. Kottelat, 14 Aug.1991; ZRC 20457–61, 5(25.5–37.5), Rembia, Malacca, D. S. Johnson, 26 Feb.1958; ZRC 1651i–iii, 3(32.0–40.5), Sungei Telok Bahang at 14.5 miles (23.2 km) on Telok Bahang Road, Penang, E. R. Alfred, 21 Oct.1961; FMNH 68465, 3(27.5–29.0), Sungai Tawan, Sungai Tibas Camp, Kalabakan, Tawau, Sabah, R. Inger, 8 Jun.1956; NTM S.14240- 001, 4(23–26), 7 miles (11.2 km) south of Kuching, Kampong Pangkalan Kuap, Sarawak, B. L. Lim, 1 Jan.1969. BRUNEI: NTM S.14239-001, 3(32–36), Sungai Belalong, KBSFC, S. Choy, 27 Jul.1992. SINGAPORE: ZRC 1049i–iv, 4(24–28), MacRitchie Reservoir, S. H. Chung, 4 Nov.1959. INDONESIA: Holotype of Glossogobius oligactis, RMNH 4459, 1(25.5), Java. Holotype of Glossogobius campbellianus, USNM 61051, 1(26.5), Buitenzorg (= Bogor Botanical Gardens), Java, D. H. Campbell. Paratype of Glossogobius campbellianus, CAS 22498, (23), same data as holotype. CMK 9621, 6(15–32), clear stream east of Mentok on road from Pangkalpinang, Banka, Sumatra, M. Kottelat et al., 4 Mar.1993.

Other material examined (but not used in description). THAILAND: KUMF uncatalogued, 8, Thasaeh Reservoir, Chumporn ; USNM 263432 , 14 , Ban Pong ; CMK 9765 , 2 , Koh Chang Island ; CMK 5350 , 5 , Phang Nga ; CAS 44347, 4 , Goh Chang Island ; CAS 53248, 1 , Goh Chang Island ; CAS 53254, 1 , Goh Chang Island ; CAS 51608, 1 , Goh Chang Island ; NTM S.14350- 042, 2, Bangpakong River ; CMK 10713, 22 , Trat Province ; SMF 13346, 4 , Lam Pi River , Phuket ; USNM 316197 , 1 , Pungah ; NTM S.14241-001, 13, Borapet Swamp, Nakonsawan. CAMBODIA : MNHN 1985.988 , 2 , Kampot River; MNHN 1985.996 , 1 , Stung Hong Kong. THE PHILIPPINES: CMK 9978 , 2 , Basey River , Samar . MALAYSIA: CAS 32976, 187 , paratypes of Vaimosa perakensis, Chanderoh Dam , Perak ; ex CAS 39485, 10 , Kota Tinggi, Johore ; ex USNM 258941 , 1 , Sungei Sedili Besar, Johore ; ZRC 32013–26 , 14 , Penang ; ZRC 35262–89 , 28 , Perak ; CMK 20510, 6 , near Kota Tinggi ; ZRC 27562–5 (in part), 1, Selangor ; FMNH 63039 , 1 , Sungei Saoh Sarawak ; FMNH 68468 , 1 , Tawau, Sabah ; FMNH 68469 , 3 , Tawau, Sabah ; FMNH 68470 , 1 , Tawau, Sabah ; FMNH 68464 , 5 , Tawau, Sabah ; ZSM / KEW 268 , 1 , on Kota Kinabalu / Sandakan road, Sabah . BRUNEI: NTM S.14237-001, 1, Belalong ; NTM S.14238-001, 1, east of Temburong . INDONESIA: CMK 9527 , 1 , Sungei Tulit, Kalimantan Timur , Borneo; BMNH 1975.8.15.387-389, 3, Ranu Klumdumgah E, Java ; CMK 6098 , 8 , Lake Sawangan , Java ; CMK 10816, 2 , Rawa Pening, Java ; CMK 6104 , 1 , Maros, Sulawesi ; RMNH 17118 , 1 , Sinaloa (possibly = Sinalud, S of Singaraja, Bali; not Sinaloa, Mexico ). NO LOCALITY : RMNH 23266 , 7 ; RMNH 23017 , 1 ; RMNH 14050 , 5 .

Diagnosis. – A moderately slender Pseudogobiopsis with second dorsal rays I,6–8 (modally I,6); anal rays I,5–7 (modally I,6); pectoral rays 16–19; longitudinal scales 22– 25; TRB 6-8; predorsal scales 6–10, large, reaching up to close behind eyes; head flattened and jaws greatly enlarged in male; preopercular pores present, posterior portion of oculoscapular canal present, including TLCP pore; scales on body mostly ctenoid; first spine of dorsal fin longest and usually filamentous in males, second or third spine longest in females, but not elongate; upper half of body with scale margins narrowly outlined with dark pigment, five elongate dark blotches along midside of body with fine dark spots below and three dark streaks on face; known from fresh waters of Indo-Malay Archipelago.

Description. – Based on 56 specimens, 18.5–46 mm SL. An asterisk indicates counts of holotype of Glossogobius oligactis .

First dorsal VI*; second dorsal I,6–7 (mean I,6*); anal I,5–7 (mean I,6*), pectoral rays 16–19 (mean 18, holotype with 19 on right, 18 on left), segmented caudal rays always 17*; caudal ray pattern 9/8; branched caudal rays 12–15 (mean 14, modally 7/7, fin ray tips broken in holotype); unsegmented (procurrent) caudal rays 7/7 to 10/10 (modally 9/9); longitudinal scale count 22–25* (mean 23); TRB 6–8 (mean 8, 7 in holotype); predorsal scale count 6*–10 (mean 7); circumpeduncular scales 12–13 (13 only in one specimen). Gill rakers on outer face of first arch 1+7 to 4+8 (modally 3+6). Pterygiophore formula 3-12210 (in 19). Vertebrae 10+15 (in two), 10+16 (in 17), 10+17 (in two). Neural spine of second and third vertebra narrow and pointed (in nine) or stout and pointed (in two). Two epurals (in 16). Two (in nine) or three (in seven) anal pterygiophores before haemal spine of first caudal vertebra. Upper rear corner of scapula ossified or not. Palatine not in contact with quadrate. Pterygoid slender, may be equal to palatine in length. Quadrate forked. Metapterygoid small, with short dorsally oriented projection, no process reaching toward or contacting quadrate (illustrated in Larson, 2001: Fig. 64).

Body compressed posteriorly, rounded to somewhat depressed anteriorly. Body depth at anal fin origin 14.0–21.6% (mean 18.4%) of SL. Head wider than deep, especially in mature males; HL 28.6–35.8% (mean 32.1%) of SL; head in mature females appearing oval in cross-section, males with head distinctly depressed. Depth at posterior preopercular margin 43.4–63.0% (mean 53.1%) of HL. Width at posterior preopercular margin 60.2–84.3% (mean 69.0%) of HL; cheeks may be inflated. Mouth terminal, slightly oblique, forming angle of 15–20° with body axis; jaws greatly enlarged in mature males, reaching well back past eye and nearly reaching angle of preopercle; immature males with jaws reaching to below rear half of eye; mature females with jaws reaching to below front half of eye or just behind eye (in holotype of Glossogobius oligactis , end of jaws protruding past preopercular edge). Lips usually smooth, fleshy fimbriae may be present anteriorly on inner edge of upper lip (fimbriae sometimes very close to outer edge); lower lip free at sides, fused across front, fleshy symphysis slightly raised. Upper jaw 36.6–81.5% (mean 40.7% in females, 59.5% in males) of HL. Eyes dorsolateral, forming part of dorsal profile, 20.4–30.2% (mean 27.4% in females, 24.4% in males) of HL. Snout flattened, rounded, 24.2–35.9% (mean 28.4%) of HL. Interorbital narrow, 11.1–19.1% (mean 13.8%) of HL. Caudal peduncle long, compressed, length 24.7–31.3% (mean 28.5%) of SL. Caudal peduncle depth 10.3–14.1% (mean 12.3%) of SL.

First dorsal fin rounded, tips of spines free, first spine nearly always longest in males (rarely second or third spine longest), spine elongate and filamentous, reaching back nearly to rear of second dorsal fin when depressed; females with no elongate first dorsal fin spines, second or third spines longest; spines barely reaching second dorsal fin origin when depressed. First dorsal spine 15.1–15.3% (mean 15.2%) in females, 14.1–41.0% (mean 25.4%) in males, of SL. Second dorsal spine length 13.2–16.8% (mean 15.0%) of SL. Third dorsal spine length 11.9–15.0% (mean 13.9%) of SL. Second dorsal and anal fins short-based, posteriormost rays longest, rays falling well short of caudal fin base when depressed. Pectoral fin slender, pointed, central rays longest, 20.4–27.9% (mean 25.0%) of SL; rays usually branched but for uppermost. Pelvic fins slender to oval, reaching to anus, 20.2–26.6% (mean 23.2%) of SL. Caudal fin relatively short, rounded posteriorly, 23.8–28.9% (mean 26.4%) of SL.

No distinct mental fraenum, chin smooth, sometimes with fleshy pad behind symphysis (usually discernible in freshly preserved material). Anterior nostril placed just above preorbital edge, in short tube oriented forward. Posterior nostril rounded to oval, placed very close to front centre margin of eye. Gill opening wide, extending forward to under opercle or just under preopercle. Inner edge of pectoral girdle smooth with no ridge or flange; only two specimens observed with single small fleshy knob. Gill rakers very short and unspined, longest rakers near angle of arch; rakers on inner face of first arch about twice height of outer rakers, as are outer and inner rakers on other arches. Tongue large, tip deeply bilobed (rarely concave); occasionally tongue blunt and reduced in size. Teeth small; teeth in outermost row of upper jaw largest, curved and pointed, placed at front of jaws; two rows of smaller pointed teeth behind this row; one or two rows of small pointed teeth at side of jaw (very little difference in size of teeth between males and females). Lower jaw with three or four rows of small pointed teeth across front, teeth in inner rows tending to point posteriorly; teeth in innermost row on side of jaw largest and stoutest (posteriormost few teeth largest); usually one or two rows of teeth at side of jaw in females; in males, only anterior half of lower jaw with teeth, posteriormost tooth largest.

Predorsal scales moderately large, evenly sized, reaching to close behind eyes; anteriormost scale broader than those behind it. Operculum with large cycloid scales, lower quarter sometimes unscaled. Cheek always naked. Pectoral base covered with few large cycloid scales. Prepelvic area covered with cycloid scales. Belly midline naked, remainder covered with cycloid or ctenoid scales, or with patch of ctenoid scales close to pelvic fin base and rest of scales cycloid. Ctenoid scales on side of body extending forward to pectoral base, sometimes extending dorsally over base. Anteriormost scales on body larger than those posteriorly.

Genital papilla in male elongate and flattened, narrowing toward tip, one or several tiny lobes at tip; in female, papilla short, rounded and bulbous, indented at tip.

Head pores present ( Fig. 25 ). Pair of nasal pores, pair of anterior interorbital pores, a median posterior interorbital pore, postorbital and infraorbital pore behind each eye, oculoscapular canal and pore over preoperculum and three preopercular pores. One specimen from Cambodia (MNHN 1985.996) with extra pore on each oculoscapular canal, close to infraorbital pore.

Sensory papillae pattern longitudinal, as in Fig. 25 . Cheek rows a, c and cp composed of large, widely spaced papillae, and rows b and d of very small, closely spaced papillae. Two to three s rows on snout, of one papilla each; middle row papilla absent or reduced in size. Mandibular f row of two papillae, one on each side of symphysis.

Colouration of fresh material. – Gerhard Ott made available photographs of captive specimens from the Chong-fa Waterfall on the Andaman coast of Thailand (Plate 2B). The head and body are translucent pearly grey, slightly yellowish to gold-speckled dorsally; belly whitish; five or six dusky internal blocks of pigment just visible through body wall and several indistinct dusky saddles on dorsum (most distinct on posterior half of body); scales with dark margins, on lower half of body, scale margins outlined with black speckles and dense black small round spots. Head pinkish-grey on lower half, dorsal half slightly yellowish to gold-speckled. First dorsal fin transparent, with alternating pale creamy yellow and faint diffuse brown bands and small black oval spot near base of fin posteriorly, elongate first dorsal spine creamy yellow, fin margin translucent. Second dorsal fin and caudal fin with closely spaced irregular alternating bands of pinkish brown and creamy yellow to pinkish, fin margins brownish. Anal fin whitish. Pectoral and pelvic fins translucent blueish white to nearly transparent.

A photograph of a living captive specimen, identified as Boleophthalmus sp. , appears in Wheeler (1979: Pl. 431). Fish light yellowish-grey, with whitish breast and abdominal region, scale margins narrowly outlined with light greyish brown (darker on back) on dorsal half of body; on ventral half of body scale margins outlined by series of small blackish dots. No dark midlateral blotches visible, but posterior half of body with about five dusky internal bars. Head (facing away from viewer) with brownish bar extending from eye toward snout tip, some brownish marks directly below eye and diagonal brown bar extending from rear of the eye across cheek. Opercle, pectoral base and pectoral fin yellowish. Both dorsal fins translucent, with rows of elongate black and light yellow spots (two rows on first dorsal fin; four or five on second); greatly elongate first dorsal fin spine broad (membranous?) and yellowish white. Caudal fin translucent yellowish with 10 rows of purplish brown small spots coalescing posteriorly into narrow lines.

Larson & Lim (2005: 143) also show a live specimen. Freshly dead specimens in available slides are similar to preserved specimens, being whitish or whitish yellow with brown and/or greyish-brown body markings and blackish spots on the dorsal fins.

Colouration of preserved material. – Head and body yellowish-white, light greyish-brown to pale brownish (depending upon preservation), paler on ventral half, with five elongate, rectangular, brown blotches along midside of body; scale margins on upper half of body outlined narrowly with brown; scales on lower half of body becoming less clearly outlined, with series of tiny black or brown spots (conspicuous against light background) ( Fig. 26 ). Five diffuse brown saddles usually visible, crossing back and reaching down to midside of body, sometimes joining midlateral blotches. Posteriormost midlateral blotch usually wedge-shaped, extending onto caudal fin base. Nape and upper half of body often with indistinct brown spotting and mottling. Ventral midline of caudal peduncle with thin black line, usually with three to four evenly spaced narrow black blotches present.

Head with three distinct brown markings: first, short broad bar from front of eye to upper lip but not extending onto lip; second, curved broad to narrow streak from lower edge of eye to jaw, bending sharply rearward and ending on middle of cheek; and third, broad diagonal bar from rear of eye extending backward to end of middle of cheek just above second streak; third bar usually darkest and broadest. Opercle with few diffuse brown spots, usually dark brown irregular marking present near upper rear corner. Lips and chin plain dusky grey to brown. Pectoral base with blackish to brown spot or blotch across bases of uppermost few fin rays. Breast and belly pale to dusky.

First dorsal fin translucent to whitish with two to three rows of elongate black spots on spines and membranes (spots often joining to form irregular rows); filamentous portion of first spine plain whitish. Second dorsal fin similar, with four to seven rows of blackish spots coalescing on posterior half of fin at least, forming wavy rows. Anal fin plain dusky grey. Caudal fin translucent to dusky with 5–10 rows of small elongate dusky spots or fine irregular dusky bars. Pectoral fin translucent to dusky. Pelvic fins translucent dusky, darkest toward fin bases.

Comparisons. – This species was found to be frequently been confused with Pseudogobiopsis siamensis in museum collections, as the two species can occur syntopically and small female specimens look superficially similar. The headpore arrangement (preopercular pores and rear portion of oculoscapular canal and pore present in P. oligactis , but absent in P. siamensis ) and caudal fin colour pattern (vertically oriented rows of brown spots in P. oligactis vs. similarly oriented grey to brown zigzag lines in P. siamensis ) are the simplest means of distinguishing the two. Additionally, P. oligactis tends to be longer bodied with a somewhat flattened head (especially in adult males), while P. siamensis is stockier, with the head depth at the preopercle greater than the width.

Distribution. – Specimens are known from Thailand through the Indo-Malayan Archipelago to Indonesia. Two specimens are known from the Philippines (but see Remarks). Ng & Tan (1999) reported the species for the first time from the Endau River system in southern Peninsular Malaysia.

This species appears to have become extinct in Singapore, with the only known specimens collected in 1959. Despite recent surveys of most habitats on the island by resident biologists, P. oligactis has not been found since ( Larson et al., 2008).

Ecology. – Freshwater, usually from fast-flowing hill streams, out of the main current. Syntopic with P. siamensis in Malaysia.

Herre (1940), in his description of Vaimosa perakensis , described how the species rapidly increased in abundance along the edges of Chanderoh Dam ( Malaysia) after it was built.

Schneider (2003) described captive spawning of specimens originally collected from Santubong Peninsula, Sarawak; the habitat was described as a small stream with pebble and rock substrate. In captivity, the male constructed burrows under stones and became golden-yellow in colour with darker scale margins (dark saddles and lines on the body vanish), a violet hue on the head and bright red fins. A ready to spawn female had a pale body with black pelvic fins. About 1,000 eggs were deposited on the roof of the spawning cave and larvae were planktonic.

Horsthemke (in litt.) observed that captive female specimens often moved up into the water column and rested on top of large stones or on the leaves of aquatic plants, while a male was strictly benthic (and cryptic in behaviour). They ate live food, but nothing larger than chironomid larvae.

Remarks. – Stigmatogobius neglectus Koumans is based on a Bleeker manuscript name, Pseudogobius neglectus , and listed as name only in Koumans (1931) and Bleeker (1983). Bleeker (1983: Pl. 438, Fig. 13 ) indicated that the black spot drawn on the fi rst dorsal fin on the figure of Pseudogobius neglectus was erroneous. Kottelat et al. (1993: pl. 70) reproduced this figure without comment.

Koumans (1940: 126) first recognised that Glossogobius campbellianus was a synonym of P. oligactis . However, he also thought that Vaimosa siamensis was also a synonym ( Koumans 1940: 135), which it is not.

Kottelat et al. (1993) combined P. oligactis and P. siamensis under their account for Pseudogobiopsis campbellianus . The specimens in their Fig. 70 are P. siamensis ; and the batch of specimens from which they came (CMK 7864) included both species. They also listed this species (as Pseudogobiopsis neglectus ) as a “... species to watch ...” due to its apparent rarity and lack of biological information about it ( Kottelat et al., 1993: xxxvi).

Roberts (1993: 44, Fig. 51) published one of Kuhl & van Hasselt’s illustrations, of a fish from Java (artist unknown) which could be Pseudogobiopsis oligactis . It is relatively slender, has an elongate first dorsal fin spine, elongate black blotches along the midside of the body, small brown spots on the whitish lower half of the body and finely barred caudal fin. However, the mouth is not enlarged and there is a black blotch on the pectoral base, features which resemble that of specimens of a probably new species not included within this paper.

There appear to be some dwarf (i.e. sexually mature at a small size) populations of this species. Thirteen specimens from Borapet Swamp , Nakornsawan Province , Thailand ( NTM S.14241-001), include 23 mm SL males with enlarged mouths and a 19 mm SL female with nearly ripe eggs. Additionally , the only specimens from the Philippines which are of this species are two very small mature fish (21 mm SL male, 17.5 mm SL female) from the Basey River , Samar ( CMK 9978 ). The male has an enormous mouth reaching to the rear of the preopercle and the female is filled with ripening ova. Both fish are very dark in colour (chocolate-brown, with whitish scale centres) and show some indistinct vertical brown bars on the side of the body. It is possible that these two specimens belong to a separate species (although basic counts agree with P. oligactis ), but additional material is required to confirm this .

Figures

Fig. 22. Pseudogobiopsis festivus, new species, holotype, 34.5 mm SL, male, ZRC 40279, near Kuching, Sarawak, Malaysia.

Fig. 26. Pseudogobiopsis oligactis, CMK 10862, 28.8 and 34.9 mm SL, locality unknown. From colour slide by Maurice Kottelat.

Fig. 4. Eugnathogobius indicus, new species, paratype, 14 mm SL, male, USNM 316139, Grande Terre, Aldabra Atoll, Seychelles.

Fig. 2. One of the 10 trees from PAUP analyses; preferred tree on which classification is based (CI = 0.4935, RI = 0.6929).

Fig. 23. Pseudogobiopsis festivus, new species, papillae pattern. 26 mm SL female, CMK 8401, Sungei Bejit, Sarawak: A, lateral view; B, dorsal view. Scale bar = 1 mm.

Fig. 13. Eugnathogobius microps, 25.5 mm SL, NTM S.13953-013, Klong Bang Sai, Phuket, Thailand.

Fig. 27. Pseudogobiopsis paludosus. Holotype of Ctenogobius paludosus Herre, CAS 32998, 30.5 mm SL male, Kota Tinggi, Johore, Malaysia.

Fig. 25. Pseudogobiopsis oligactis, papillae pattern. 36 mm SL male, CMK 5385, Ranong, Thailand. Scale bar = 1 mm.