97.5 Encheliophis gracilis: 15.5 em (Aldabra).
Genus Encheliophis Muller, 1842
Upper jaw bound by skin to side of head . Four species, 1
in our area.
97.5 Enche/iophis gracilis
(Bleeker, 1856)
Graceful pearlfish
Sierlike perelvis
Oxybeles gracilis Bleeker, 1856: 105 (Banda Ids. , Indonesia). Fierasfer
punctatus: Barnard, 1927: 886. Carapus punctatus: Smith, SFSA No. 1008.
lordanicus gracilis: Smith , SFSA No.1010*; 1955: 404'; Trott, 1970: 17.
lordanicus punctatus: Smith, 1955: 405. Encheliophis (lordanicus)
gracilis: Arnold , 1956: 299* .
Prays 17-18; precaudal vertebrae 26-31; branchiostegal rays 7; olfactory rosettes with 23 pairs of lamellae. Vomer with a median row of about
3 teeth.
Colour in life: dark, with evident pigment spots; bluish
tinge in males, yellowish in females ; caudal spots metamerically arranged; double row of spots along LL; middorsal line from D origin to rear of head; P pigmented
(Trott, 1970). (At Pinda a live specimen collected in 1956
had iris metallic silver under transparent skin, belly (unspotted area) metallic silver, spotted area transparent with
numerous black spots. - M.M. Smith.) Attains 30 cm. IndoWest Pacific; to Natal. Recorded from starfish (Culcita diseoidea) and sea cucumbers (Holothuria sea bra and H.
argus). In the latter, reported by Trott (1970) to form male/
female pairs (females larger) and to parasitise hosts.
Genus Onuxodon Smith, 1955
Median rocker bone at anterior end of swimbladder
presumably used in sound production (Courtenay &
McKittrick, 1970). Two species; both in our area. Carapus
reedi Smith, 1955: 410, described from Durban, is a juvenile
Onuxodon, as suggested by Arnold (1956).
97.6 Onuxodon margaritiferae: 9.5 em (Durban) .
97.7 Onuxodon parvibrachium: 10 em and enlarged canine teeth (Seychelles).
97: CARAPIDAE (PEARLFISHES)
KEY TO SPECIES
la P less than 30% head length ... . . . .. . ... . O. parvibrachium
Ib P more than 30% head length ...... . .. . .. . O. margaritiferae
Pearlfish
97.6 Onuxodon margaritiferae
(Rendahl,1921)
Perelvis
Fierasfer margaritiferae Rendahl , 1921: 5 (Cape Jaubert , Northwest
Australia) . lordanicus caninus (non Gunther) : Fowler, 1927: 30, Fig. 5.
lordanicus fowleri Smith , 1955: 403 (on 1. caninus of Fowler, 1927; Christmas Id .). Carapus margaritiferae: Smith, 1955: 408*; 1961: 571, No.
l009a. Carapus (Onuxodon) margaritiferae: Arnold, 1956: 285 *. Onuxodon margaritiferae: Trott & Trott, 1972: 842.
P length 28-54% head length ; Prays 16; precaudal vertebrae 20-22.
Translucent in life, with pink sheen and dusky caudal.
Attains 9 cm. Indo-West Pacific to Durban; reported to live
in "clams" (Smith, 1955). Trott & Trott (1972) found this
species in the mantle cavity of the giant rock oysters (Pyenodonta hyotis) in the Philippines; it feeds on crustaceans
and polychaetes and exhibits a tendency towards sexual
pairing in the host.
97.7 Onuxodon parvibrachium
(Fowler, 1927)
Oyster pearlfish
Oester-perelvis
Carapus parvibrachium Fowler, 1927: 31 , Fig. 6 (Suva , Fiji) . Onuxodon
parvibrachium: Smith , 1955: 406*; Tyler, 1970; Trott & Trott, 1972.
P length 16-30% head length ; Prays 14-15 ; precaudal vertebrae 17-20,
caudal vertebrae 48-65; lor 2 laterally compressed canine teeth at front of
each dentary and premaxilla; elongate patches of small teeth on dentaries,
premaxillae, vomer and palatines.
Translucent in life with pink sheen ; preserved specimens
with dark pigment at bases of D and A rays and along
-
353
Genus Encheliophis Muller, 1842
Upper jaw bound by skin to side of head . Four species, 1
in our area.
97.5 Enche/iophis gracilis
(Bleeker, 1856)
Graceful pearlfish
Sierlike perelvis
Oxybeles gracilis Bleeker, 1856: 105 (Banda Ids. , Indonesia). Fierasfer
punctatus: Barnard, 1927: 886. Carapus punctatus: Smith, SFSA No. 1008.
lordanicus gracilis: Smith , SFSA No.1010*; 1955: 404'; Trott, 1970: 17.
lordanicus punctatus: Smith, 1955: 405. Encheliophis (lordanicus)
gracilis: Arnold , 1956: 299* .
Prays 17-18; precaudal vertebrae 26-31; branchiostegal rays 7; olfactory rosettes with 23 pairs of lamellae. Vomer with a median row of about
3 teeth.
Colour in life: dark, with evident pigment spots; bluish
tinge in males, yellowish in females ; caudal spots metamerically arranged; double row of spots along LL; middorsal line from D origin to rear of head; P pigmented
(Trott, 1970). (At Pinda a live specimen collected in 1956
had iris metallic silver under transparent skin, belly (unspotted area) metallic silver, spotted area transparent with
numerous black spots. - M.M. Smith.) Attains 30 cm. IndoWest Pacific; to Natal. Recorded from starfish (Culcita diseoidea) and sea cucumbers (Holothuria sea bra and H.
argus). In the latter, reported by Trott (1970) to form male/
female pairs (females larger) and to parasitise hosts.
Genus Onuxodon Smith, 1955
Median rocker bone at anterior end of swimbladder
presumably used in sound production (Courtenay &
McKittrick, 1970). Two species; both in our area. Carapus
reedi Smith, 1955: 410, described from Durban, is a juvenile
Onuxodon, as suggested by Arnold (1956).
97.6 Onuxodon margaritiferae: 9.5 em (Durban) .
97.7 Onuxodon parvibrachium: 10 em and enlarged canine teeth (Seychelles).
97: CARAPIDAE (PEARLFISHES)
KEY TO SPECIES
la P less than 30% head length ... . . . .. . ... . O. parvibrachium
Ib P more than 30% head length ...... . .. . .. . O. margaritiferae
Pearlfish
97.6 Onuxodon margaritiferae
(Rendahl,1921)
Perelvis
Fierasfer margaritiferae Rendahl , 1921: 5 (Cape Jaubert , Northwest
Australia) . lordanicus caninus (non Gunther) : Fowler, 1927: 30, Fig. 5.
lordanicus fowleri Smith , 1955: 403 (on 1. caninus of Fowler, 1927; Christmas Id .). Carapus margaritiferae: Smith, 1955: 408*; 1961: 571, No.
l009a. Carapus (Onuxodon) margaritiferae: Arnold, 1956: 285 *. Onuxodon margaritiferae: Trott & Trott, 1972: 842.
P length 28-54% head length ; Prays 16; precaudal vertebrae 20-22.
Translucent in life, with pink sheen and dusky caudal.
Attains 9 cm. Indo-West Pacific to Durban; reported to live
in "clams" (Smith, 1955). Trott & Trott (1972) found this
species in the mantle cavity of the giant rock oysters (Pyenodonta hyotis) in the Philippines; it feeds on crustaceans
and polychaetes and exhibits a tendency towards sexual
pairing in the host.
97.7 Onuxodon parvibrachium
(Fowler, 1927)
Oyster pearlfish
Oester-perelvis
Carapus parvibrachium Fowler, 1927: 31 , Fig. 6 (Suva , Fiji) . Onuxodon
parvibrachium: Smith , 1955: 406*; Tyler, 1970; Trott & Trott, 1972.
P length 16-30% head length ; Prays 14-15 ; precaudal vertebrae 17-20,
caudal vertebrae 48-65; lor 2 laterally compressed canine teeth at front of
each dentary and premaxilla; elongate patches of small teeth on dentaries,
premaxillae, vomer and palatines.
Translucent in life with pink sheen ; preserved specimens
with dark pigment at bases of D and A rays and along
-
353