7006

• UCREFRP Catalog Number: 7006
• Author: Gustafson, E.
• Title: Early Development, Adult Sexual Dimorphism, and Fecundity of the Razorback Sucker,
• USFW Year: 1975
• Copyright Material: NO

Ad.ul~ :),~:\ual .uL,_Ol'pili sm in J.... texs,~1U~

lL tot~l of six sexually di~orphic criaracteristics have been

I'ound for Xyrauchen. '1.',"0 ciuj,rac tari stl c s, d.iulo1'phl c coloration. and

tuberculation, are apparent only during the spaHl1ing period (Feo.ru-

ary to JUde, al~hough somE: of these characteristics may be expressed

&s early as Nuvember).

l~'our l'G:tJrescl.t sexil~ criteria which are in-

Q.~pendeilt. of seasun:

(1) J..lrfE;.ren.~ial size (l:;ast~d. 0,(1 st&nJ.f.~rd le.agth

a.rd tot-al vleigl'lt), (2) differen"Gial pelvic alId (J) anal fin leng'ths,

FiLlU (4) ct.i fferelll,iG.l . urogeni tal f-b.pillae leng th and morphology.

1'1a1e and i emale XYl'8.uche,n exhi oi c dLwrpnic pigmel1tatio'::l

t0ouSL...s, 1'752; l\linckley, 197J) and. tubarculat..ion during the o1'eed-

ill~ seaSOfi. The males are generally dark-olivaceous to black dorsal-

ly vii th d. bright-ol'a.nge uelly a..:Id a dark:..pink or reddish lateral

s~riplJ. :Large, GO~.I.1cal tuber~les are produced on the anal fins and

"

lower lobe caudal fins.

8,-l1a1le1', cOLl1cal tubercles are fOUI1d on the

f'ectoral and pelvic fins anJ. alo.L:.g th~ sides anu vent.:culll of the caud":,,

<:AI peduucle.

BransQl! (1961 & 1966) reported tu'uerculatio.no.clly on

;;he al.l.dJ. 11L.l.3 of m.::.le .I...yr~he.i1.

1.1.1 feIl1ale s. colo.l'at 10Li remains

.I.!ul'l~i;.1.1 t.IU':'OU8~Wu ~ tile 3P::iWf.iil.lg season: ,all vaceous Jorsally, 1 ight,t.:n-

iHe to Ol'f-Wf~i::'..:: V.c:Ht.c:::.ll,,'

. - ~
\ 0()~6l.b.S.

1952;

j'JiIlckley,

197J).

'i'uber-

~ "P'.'!7~-"~~""J""'''"','7'~_"",,~?' ~- .. T(I'

"""'~'l>'