Oryzias sarasinorum Parenti, 2008

Parenti, Lynne R., 2008, A phylogenetic analysis and taxonomic revision of ricefishes, Oryzias and relatives (Beloniformes, Adrianichthyidae), Zoological Journal of the Linnean Society 154 (3), pp. 494-610 : 583-585

ORYZIAS SARASINORUM ( POPTA, 1905) COMB. NOV.

SARASINS’ BUNTINGI

FIGURE 54

Haplochilus sarasinorum Popta, 1905: 239 [type locality: Indonesia: Sulawesi Tengah, Lake Lindu].- Nijssen et al., 1982: 70 [ZMA type specimens].

Xenopoecilus sarasinorum .- Regan, 1911a: 373 [as type by monotypy of new genus, Xenopoecilus ].- Weber & de Beaufort, 1922: 378 [comparisons, distribution].- Rosen, 1964: 222–263 [in part, comparative anatomy, relationships, classification].- Parenti, 1987: 561 [in part, characters, comparisons].- Whitten et al., 1987a: 295, table 4.10 [Sulawesi, distribution].- Kottelat & Sutter, 1988: 55 [note on type material].- Bleher, 1989: 30–32 [photograph, report of collection from Lake Lindu, Sulawesi Tengah].- Kottelat et al., 1993: pl. 44 [photograph of female carrying cluster of embryos].- Seegers, 1997: 15, 18 [listed, photograph].- Sovrano et al., 1999: 175– 180; Sovrano et al., 2001: 237–244; Sovrano, 2004: 385–391 [left-eye preference, brain specialization].- Parenti, 2005: 24 [photograph].

Xenopoecilus saracinorum . Incorrect spelling.- Naruse et al., 1994: 47–52 [biology, comparisons].- Naruse, 1996: 3–7, figs 2–4 [relationships, karyology].

Xenopoecilus sanarisorum . Incorrect spelling.- Böhm, 1997: 642 [report from Lake Lindu; photographs].

Differential diagnosis: Oryzias sarasinorum is unique among ricefish in having a broad, silvery, lateral band that extends from the posterior margin of the head to the caudal peduncle in life and in some preserved specimens. The species is distinguished from other Oryzias , and is more similar to Adrianichthys species , by having a high number of scales in a lateral series (70–75 vs. 24–54). It is further distinguished from congeners by palatine and quadrate bones articulating via elongate flanges anteriorly, and by having 15, rather than 14 or fewer, precaudal vertebrae. Like A. oophorus , it is a pelvic brooder.

Description: Elongate, maximum size of specimens examined 58 mm SL. Body slender, elongate, laterally compressed; body depth 13–15. Size and extent of abdominal concavity between pelvic fins and anal fin could not be determined. Mouth terminal, upper and lower jaws slightly elongate; lower jaw extends beyond upper jaw. Dorsal and ventral body profile nearly straight from head to dorsal- and anal-fin origins. Head length 29; snout length 11; eye moderate, 9, orbits do not project beyond dorsal surface of head. Fleshy, incompletely scaly, basal portion of dorsal and anal fin project slightly beyond primary body profile. Scales small, cycloid and relatively deciduous; 70–75 in a lateral series. Elongate, filamentous dorsal- and anal-fin rays in males; anal-fin rays without bony contact organs. Medialmost pelvicfin ray not connected to body via a membrane. Caudal fin slightly lunate, dorsal and ventral segmented caudal-fin rays longer than middle rays. Urogenital papilla single-lobed in females. Males with subconical tubular urogenital papilla.

Premaxilla short and broad with distinct ascending process; premaxilla and dentary with two to three irregular rows of caniniform teeth; enlarged, caniniform teeth posteriorly on the premaxilla and dentary of males. No preethmoid cartilage; ossified portions of mesethmoid disc-shaped; anterior border of ethmoid cartilage irregular. Palatine and quadrate articulate via elongate flanges that overlap anteriorly. Dorsal ramus of hyomandibula not distinctly bifid, single cartilage articulates with sphenotic and pterotic. Lacrimal sensory canal carried in open bony groove. First pleural rib on parapophysis of third vertebra; lateral process of pelvic bone attaches to fifth pleural rib. Caudal skeleton with two epural bones; one ventral accessory bone. Fifth ceratobranchial toothplates subtriangular, with pavement dentition anteriorly, followed by five to six discrete rows of unicuspid teeth; small, incomplete posterior row in males. Basihyal bone triangular, basihyal cartilage elongate and rectangular. Epibranchial elements fully ossified; epibranchial 2 notably smaller than the other epibranchial elements.

Dorsal-fin rays 11–12. Anal-fin rays 21–22. Pelvicfin rays 7. Pectoral-fin rays 10–11. Principal caudalfin rays i,5/6,i. Procurrent fin-rays, dorsal 6, ventral 6–8. Vertebrae 34(15 + 19). Branchiostegal rays 5–6.

Cytogenetic data: A fused chromosome constitution ( Naruse, 1996: 6, fig. 3) with two pairs of large metacentric chromosomes. Chromosome constitution of O. sarasinorum is otherwise considered to be poorly known.

Colour in life: Ground colour beige-yellowish with a ‘central “luminous” stripe’ that reflects light strongly ( Bleher, 1989: 32).

Colour in alcohol: Ground colour pale yellow, belly pale whitish yellow. A broad, silvery, lateral band extends from posterior margin of the head to caudal peduncle in some specimens, other specimens bleached. A diffuse row of melanophores from the dorsal surface of the head to the dorsal-fin origin, an irregular, midlateral black line from the posterior border of the head to base of the caudal fin. Fins hyaline to dusky.

Distribution and habitat: Endemic to Lake Lindu, Sulawesi Tengah ( Parenti & Soeroto, 2004: fig. 1). Oryzias sarasinorum is a pelagic species; adults live in the open waters of Lake Lindu ( Bleher, 1989; Böhm, 1997); females carry clusters of embryos between the pelvic fins and abdomen.

Remarks: The description of Haplochilus sarasinorum was based on ‘ 25 Exemplare von 57–69 mm. [total] Länge’ ( Popta, 1905: 239). Part of the syntypic series, collected from Lake Lindu by Fritz and Paul Sarasin, vii.1902, has been examined, below. Additional syntypes in the Naturhistorisches Museum Basel, Switzerland (see Kottelat & Sutter, 1988: 55), not examined by me, are: NMBA 1014–1020 (7), NMBA 1032–1037 (6) and NMBA 1040 (1). I do not designate a lectotype from among the syntypes because I have been unable to locate the entire type series. Also, the poor condition of examined syntypes precludes the advantage of designating any one specimen as the primary type. The bodies of many specimens are dehydrated and distorted (see illustration in original description), making some measurements imprecise, in particular depth of the body and of the caudal peduncle. The two ricefish species now known from Lake Lindu, Oryzias sarasinorum ( Popta, 1905) and Oryzias bonneorum , described above, cannot be confused given the material at hand. Popta (1905) clearly indicated that her new species had 75 scales in a lateral series and remarked on the silvery body, characters of O. sarasinorum , not O. bonneorum . One of Popta’s (1905) syntypes, AMNH 20481, a specimen cleared and stained some decades ago, agrees better with O. bonneorum than O. sarasinorum in having, for example, 13 + 18 = 31 vertebrae. Another common name for this species is Sarasins’ minnow ( Seegers, 1997: 18). The second specimen in AMNH 20481 was probably the one illustrated in Rosen (1964). If so, some of his illustrations are probably of O. bonneorum , not O. sarasinorum . The outline drawings of O. sarasinorum on Rosen’s (1964) figure 3D,E are probably of that species.

Material examined: Fourteen specimens (35–58 mm SL).

Syntypes. INDONESIA. Sulawesi Tengah: Lake Lindu : RMNH 7664 , 3 (54–58 mm), ZMA 100.648 , 1 (54 mm), BMNH 1914.2.13 : 26–27, 2 (55–57 mm), formerly in NMBA, and AMNH 20481 (ex. ZMA 100.648 ), 2 [possibly = O. bonneorum ] (35 mm and a second heavily dissected specimen of unrecorded SL, both cleared and stained for bone), F. & P. Sarasin, vii.1902 .

Non-type specimens. INDONESIA. Sulawesi Tengah: Lake Lindu , C. Bonne, iv.1939, ZMA 100.649 , 2 , dehydrated, (39–58 mm), 2.5 km N of Tomato, H. Bleher, 24.vi.1989, CMK 6556 , 3 , males, (42.6–49.7 mm, the largest cleared and counterstained for bone and cartilage), CMK 6557 , female, (53.4 mm) .

Figures

Figure 54. Oryzias sarasinorum (Popta, 1905), Lake Lindu, Sulawesi Tengah, Indonesia, female, CMK 6557, 53.4 mm SL, carrying a cluster of embryos between pelvic fins and body.