Gill opening broad, extending forward to vertical at posterior edge of orbit; gill membranes attached only anteriorly to isthmus, with no free fold; gill rakers slender, longest about equal in length to longest gill filaments of first gill arch
3), and the association is assumed to represent one individual for the following reasons: 1) all skeletal elements belong to the same taxon; 2) all gill rakers are within a size range found on a single gill arch
(Hovestadt and Hovestadt-Euler, 2011, p.
The maxilla and premaxilla are the bones over the palatoquadrate, and the dentary is the dermal bone over Meckel's cartilage (these, remember, were once the mandibular gill arch
, situated in the second head segment).
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.
Rakers in the first gill arch
were short and lobular ranging in number from 9 to 14 elements, which suggest adaptation to capture larger preys (Table 1; Figure 3c).
Gill rakers modified, closely but irregularly set, mostly alternating (especially on gill arch
one), often paired on the outer and inner sides of each gill arch
(central part of arches two and throe); plates flattened, triangular, similar in shape to those in P.
Lower limb of the first gill arch
with 36 to 40 (mode = 38) thin elongate gill rakers, closely approximated.
It differs from the Red Sea species in having 13-14 rakers (versus 16-18) on the first gill arch
and several colour pattern differences.
Host species identification was confirmed by examining the gill rakers on the first gill arch
on the blind side, and by counting supraorbital pores (Orr and Matarese, 2000).
Leading edge of lower limb of first gill arch
with 8 elongate gill rakers on each side in single cleared and stained specimen.
Measurements are expressed as times in standard length: gill rakers on first gill arch
6+9=15 (6+10=16); pored scales in lateral line scale row 23 (23); median predorsal scales 17 (18); circumferential scales (in front of pelvic fins) 13 (13); circumpeduncular scales 13 (13); peduncular scales (from base of last anal fin ray to end of hypural plate) 9 (9); dorsal fin rays 20 (20); anal fin rays 27 (28); pectoral fin rays 7 (7); pelvic fin rays 5 (5); and caudal fin rays i7+7i (i8+8i); head 3.
Identification: D II-VI (9-13), A II-IV 9-15, dorsal fin high and pointed, adipose fin present, pelvic fins with well developed axillary process, vertebrae 65-68, manubrium absent, with hook-shaped processes on the capitulum, anterior edge of hyomandibular round, only 19 to 26 gill rakers present on lower limb of first gill arch