Oryzias bonneorum, 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 : 554-555

ORYZIAS BONNEORUM SP. NOV.

BONNES’ BUNTINGI

FIGURES 5A , 7A , 8B , 11B, 23B , 24E , 26D , 28B , 38

Xenopoecilus sarasinorum .- Rosen, 1964: 222–263 [in part, comparative anatomy, relationships, classification].- Rosen & Parenti, 1981: 10 [in part, characters]-. Parenti, 1987: 561 [in part, characters, comparisons].-?Kottelat et al., 1993: pl. 44 [photo of adult male].

Differential diagnosis: Oryzias bonneorum is readily distinguished from O. sarasinorum , the other Lake Lindu endemic, by its relatively deeper body (17–20% SL as opposed to a relatively slender 13–5% SL), male pigment pattern with up to nine brownish vertical bars on the side of the body (as opposed to a silvery lateral band), 36–39 scales in a lateral series (as opposed to 70–75), and 31–32 vertebrae (as opposed to 34).

Description: Data for the holotype and three paratypes are summarized in Table 6. Elongate, maximum size of specimens examined 52 mm SL (male holotype). Body laterally compressed; body depth 17–20 [19]. No pronounced abdominal concavity between pelvic fins and anal fin. Mouth terminal, upper and lower jaws slightly elongate; lower jaw extends beyond upper jaw. Dorsal and ventral body profile somewhat convex from head to dorsal- and anal-fin origins. Head length 31–32 [31]; snout length 7–9 [9]; eye moderate 9–10 [10] 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 large, cycloid and relatively deciduous; 36–39 [38] in a lateral series. Elongate, filamentous dorsal- and analfin rays in males; anal-fin rays without bony contact organs. Medialmost pelvic-fin 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, everted in some preserved specimens.

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. No flanges on the ventral surface of the palatine and the quadrate. 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 12–13 [13]. Anal-fin rays 19–20 [20]. Pelvic-fin rays 6. Pectoral-fin rays 11–12 [11]. Principal caudal-fin rays i,5/6,i. Procurrent fin-rays, dorsal 4–5 [5], ventral 5–6 [6]. Vertebrae 31–32 [32] (12– 13 + 19). Branchiostegal rays 5–6 [5].

Cytogenetic data: Unknown.

Colour in life: Unknown.

Colour in alcohol: Ground colour brownish overall. Up to nine faded vertical brownish bands in the three adult males. Fins hyaline to dusky.

Distribution and habitat: Endemic to Lake Lindu, Sulawesi Tengah ( Parenti & Soeroto, 2004: fig. 1), and probably a pelagic species like its congener, O. sarasinorum .

Remarks: Characters of this species have probably been described in the literature as those of Xenopoecilus sarasinorum Popta, 1905 , classified herein as Oryzias sarasinorum , the only other ricefish known from Lake Lindu. This species may have internal fertilization and therefore is also possibly livebearing. Additional specimens, including fresh material, are required to understand better the reproductive biology of O. bonneorum . Scale pockets were counted to estimate number of scales in a lateral series in all specimens counted; numbers are relatively accurate, but not precise. Nonetheless, they are sufficient to separate this species from O. sarasinorum , the other Lake Lindu endemic.

Etymology: The trivial name bonneorum to honour C. Bonne and J. Bonne-Wepster, systematic entomologists who worked throughout Indonesia in the early 20 th century and collected fish to determine if they were eating mosquito larvae.

Material examined: Six specimens (38.5–52 mm SL).

Holotype. INDONESIA. Sulawesi Tengah: Lake Lindu , C. Bonne, iv.1939, MZB 15499, male, 52 mm SL.

Paratypes. INDONESIA. Sulawesi Tengah: Lake Lindu , ZMA 123.863 , 5 , (38.5–45 mm, of which a male, 41 mm and a female, 40 mm, have been cleared and counterstained), collected with the holotype .

Figures

Figure 5. A, Oryzias bonneorum, ZMA 123.863, adult male, 41 mm SL; B, Nomorhamphus rossi, USNM 363187, adult female, 67 mm SL. Anterior portion of skull and outer jaws. Rostral cartilage and vomer are absent in all adrianichthyids, present in other beloniforms. Large teeth on the posterior ramus of the premaxilla are indicated by a star in A.

Figure 7. A, Oryzias bonneorum, ZMA 123.863, adult male, 41 mm SL. B, Belonesox belizanus, USNM 134595, adult male, 80 mm SL. Lateral view of gill arches to demonstrate complex, branched, cartilaginous ceratobranchial epiphysis. Elongate cartilage associated with ceratobranchial one is starred in B. Anterior is up.

Figure 8. A, Adrianichthys oophorus, USNM 350469, subadult, 41 mm SL; B, Oryzias bonneorum, ZMA 123.863, adult female, 40 mm SL. Diagrammatic representation of jaws and jaw suspensorium drawn to same scale. Dashed line approximates outline of Meckel’s cartilage. Anterior is to the left.

Figure 23. A, Adrianichthys poptae, USNM 322423, adult female, 168 mm SL; B, Oryzias bonneorum, ZMA 123.863, adult female, 40 mm SL. Diagrammatic representation of the hyomandibula. Both drawn to same scale.

Figure 24. A, Hemirhamphodon kuekenthali, USNM 330828, adult male, 50 mm SL; B, Adrianichthys roseni, USNM 322425, adult female, 73 mm SL; C, Adrianichthys poptae, USNM 322423, adult female, 168 mm SL; D, Adrianichthys oophorus, USNM 348386, female, 60 mm SL; E, Oryzias bonneorum, ZMA 123.863, adult female, 40 mm SL; F, Oryzias dancena, USNM 342156, adult male, 24.5 mm SL. Diagrammatic representation of the hyoid bar. Arrows indicate posterior extent of the ramus of the ventral hypohyal. Beloniform fishes lack an interhyal. All drawn to same scale.

Figure 26. A, Oryzias setnai, CAS 56255, male, 18 mm SL, SEMX134. B, Oryzias javanicus, CAS 58026, adult male, 26 mm SL, SEMX53. C, Oryzias celebensis, CAS 58034, adult female, 29 mm SL, SEMX40, teeth on right half of toothplate dislodged during specimen preparation. D, Oryzias bonneorum, ZMA 123.863, female, 40 mm SL, SEMX23. SEM of a right fifth ceratobranchial bone and toothplate. Anterior is up.

Figure 28. A, Nomorhamphus rossi, USNM 363187, adult male, 45 mm SL; B, Oryzias bonneorum, ZMA 123.863, adult male, 41 mm SL. Diagrammatic representation of pelvic bones and their position relative to the pleural ribs. Numbers above pleural ribs denote the vertebra to which the rib is attached. Scale bar = 1 mm.

Figure 38. Oryzias bonneorum sp. nov., holotype, Lake Lindu, Sulawesi Tengah, Indonesia, male, MZB 15499, male, 52 mm SL.