first pharyngeal arch

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Related to First branchial arch: mandibular arch, Second branchial arch

first pharyngeal arch

the first postural arch in the branchial arch series.
Synonym(s): mandibular arch

first phar·yn·ge·al arch

(fĭrst fă-rinjē-ăl ahrch)
First postural arch in the branchial arch series.
Synonym(s): mandibular arch.
References in periodicals archive ?
Diagnosis: Astyanax minor is distinguished from Iguacu Astyanax by combination of following characters: infraorbital 3 deep but not in contact with preopercle, leaving a narrow naked area between its border and preopercle; premaxillary external series with 4-6, usually 5 or 6 pentacuspid or heptacuspid teeth; first branchial arch 9-12, usually 10 rakers in upper branch and 13-16, usually 14 or 15 rakers in lower branch; a narrow and elongated vertical humeral bar.
Gill-rakers moderate in size; first branchial arch with 9-12, usually 10 rakers in epibranchial, and 13-16, usually 14 rakers in ceratobranchial + hipobranchial.
minor is a form of Astyanax with 24-28 gill-rakers in first branchial arch, while A.
Diagnosis: Astyanax bifasciatus can be distinguished from all other Astyanax from the Iguacu basin by the combination of the following characters: infraorbital 3 deep, but not in contact with preopercle, leaving a narrow naked area between border and preopercle; premaxillary external series with 4 (rarely 5) pentacuspid teeth; non-symphysial teeth in premaxillary internal series heptacuspid; vertical humeral bar with dorsal portion much wider than ventral portion; a faint and diffuse "post-humeral" spot; lateral line with 36-40 scales, usually 37 or 38; first branchial arch with 7-9, usually 8, rakers in upper branch and 10-13, usually 12, rakers in lower branch.
Gillrakers moderate in size; first branchial arch with: 8-9, usually 8 rakers, in epibranchial and 11-13, usually 12 in ceratobranchial + hipobranchial.
Similarly, there is an apparent modal difference in the total number of gill rakers on the first branchial arch between A.
Distinguished from all other congeners by the combination of the following features: anterior portion of trunk slightly wider than deep, jaws short, snout blunt, tip of anal fin rounded in male, caudal fin elliptical to acuminate in male, pelvic-fin tip reaching the anterior portion of the anal-fin base in male, dorsal-fin origin posterior to anal-fin base, dorsal-fin rays 5-7, anal-fin rays 9-11, frontal squamation S-patterned, contact organs absent, frontal scales arranged circularly, canal preopercular short and opened, longitudinal series of scales 29-32, gill rakers of first branchial arch 1 + 7, oblique rows of red dots on flank in male, transverse black bar through the chin, and no black spot on dorsal portion of caudal-fin.
Distinguished from all other congeners by the combination of the following features: anterior portion of trunk wider than deep, jaws short, snout blunt, tip of anal fin rounded in male, caudal fin elliptical to acuminate in male, pelvic-fin tip not reaching to urogenital papilla in male, dorsal-fin origin posterior to anal-fin base, dorsal-fin rays 5-6, anal-fin rays 8-10, frontal squamation S-patterned, frontal scales arranged circularly, canal preopercular short and opened, contact organs absent, longitudinal series of scales 32-34, gill rakers of first branchial arch 1 + 7, dark brown oblique bars on flank, transverse black bar through the chin, and no black spot on dorsal portion of caudal fin.
Distinguished from all other congeners by the combination of the following features: anterior portion of trunk slightly deeper than wide, jaws short, snout blunt, tip of anal fin rounded in male, caudal fin rounded in male, pelvic-fin tip reaching the anterior portion of the anal-fin base in male, dorsal-fin origin on vertical between base of 9th and 10th anal-fin rays, dorsal-fin rays 7-8, anal-fin rays 11-13, frontal squamation E-patterned, frontal scales arranged circularly, canal preopercular short and opened, contact organs on flank scales in male, longitudinal series of scales 29-32, gill rakers of first branchial arch 1 + 7, longitudinal rows of reddish brown dots stripes on flank in male, jaws black, and round black spot on dorsal portion of caudal-fin in female.
Distinguished from all other congeners by the combination of the following features: anterior portion of trunk slightly deeper than wide, jaws short, snout blunt, tip of anal fin pointed in male, caudal fin rounded in male, pelvic-fin tip reaching urogenital papilla in male, dorsal-fin origin on vertical between base of 6th and 8th anal-fin rays, dorsal-fin rays 7-8, anal-fin rays 9-10, frontal squamation S-patterned, frontal scales arranged transversely, canal preopercular absent, contact organs absent, longitudinal series of scales 29-30, gill rakers of first branchial arch 1 + 6, longitudinal rows of red dots on flank in male, transverse dark brown bar through the chin, and no distinctive black spot on dorsal portion of caudal-fin.
There is also a possible difference in the number of gill rakers on the first branchial arch.
The anterior two-thirds originates from the paired lateral lingual swellings that are contributed by the first branchial arch.