19 
ter examined for ingested Catonotus. One 121-mm cephalus jacksoni. A total of 194 of these worms was 
americanus contained a recently ingested 44-mm removed from the intestines of 240 darters. The 
squamiceps. No other evidence of predation was _ infestation was more severe in Big Creek (0.91 worms 
und. per darter) than in Ferguson Creek (0.53), and 
more severe in large darters (as many as 19 worms in 
irasitism . . a 69-mm male) than in small. In Ferguson Creek 
Both study populations of E. squamiceps were these worms were found only in darters collected 
avily parasitized by a spiny-headed worm, Acantho- from February through May and in August, but in 
TABLE 10.—Characteristics of Etheostoma squamiceps (24 specimens), E. kennicotti (24 specimens) and a hybrid 
squamiceps x E. kennicotti, all from southern Illinois. 
en 
EB. squamiceps EH. kennicotti 
Characteristic Standard Hybrid Standard 
Range Mean Deviation Range Mean Deviation 
imber of lateral-line scales 48-54 50.5 2.0 46 39-46 42.6 1.8 
imber of pored lateral-line scales 25-40 33.8 3.4 30 14-25 19.7 3.0 
imber of scales around caudal peduncle 17-21 19.6 1.2 20 17-20 18.3 0.8 
mber of vertical bands on caudal fin 6-9 7.6 0.8 7 8-11 9.3 0.8 
mber of dorsal spines 7-9 8.3 0.6 8 6-8 17. 0.5 
mber of dorsal rays 12-14 Hda0) 0.4 18} 11-13 PAA 0.5 
mber of pectoral rays 10-12 ial 0.4 12 11-13 12.0 0.2 
ctoral fin length/standard length 0.21—0.25 0.23 0.01 0.26 0.23-0.28 0.25 0.01 
inous dorsal fin base length/ 
standard length 0.21—-0.24 0.23 0.01 0.23 0.23-0.28 0.26 0.01 
inous dorsal fin base length/ 
soft dorsal fin base length 0.87-1.04 0.94 0.06 1.00 0.73-0.91 0.81 0.06 
inous dorsal fin height/ 
soft dorsal fin height 0.50—0.86 0.62 0.08 0.54 0.44-0.55 0.47 0.03 
inous dorsal fin height/body depth 0.35—-0.52 0.46 0.05 0.39 0.35-0.43 0.39 0.02 
pe squamation Fully scaled Partially scaled Naked 
lly squamation Fully scaled Fully scaled Variable naked strip 
rsal fin pigmentation Without marginal band Light marginal Distinct marginal band 
band 
udal spots 
Three black spots Three black spots No black spots 
TABLE 11.—Summary of life-history information on Big Creek and Ferguson Creek populations of Htheostoma 
Lamiceps. 
———— oo 
Characteristic 
ncipal habitat of adults 
ncipal habitat of young 
2 at reaching sexual maturity 
2 at first spawning 
e at reaching sexual maturity 
ual dimorphism 
eding tubercles 
mber of mature ova counted 
cription of egg in nest 
wning period 
Wning habitat 
Wning position 
ting site 
nber of eggs counted in nests 
. guarding 
ubation periods 
uence of sex on growth rate 
\sity 
ratio among young 
gevity 
imum size 
Tations 
ritoriality 
icipal diet 
Life-History Data 
Slab riffles in Ferguson Creek; slab pools in Big Creek 
Slab riffles in Ferguson Creek; slab pools in Big Creek 
1 year 
Females 1 year; males 2 years 
Females about 35 mm; males about 40 mm 
Males are larger, have longer fins and a deeper caudal peduncle, and in spring 
are much more boldly patterned 
Absent 
28-357 
1.8 mm in diameter, translucent, adhesive 
From late March to May or early June 
Slab pools 
Both male and female briefly inverted, head to head 
Underside of a slab stone 
8-1500 
Only by the male 
270-275 hours at 18°-22° C, 125-130 hours at 22°-26° CG 
By the third year males are significantly larger than females 
Up to 9.6 darters/m? in slab riffles in Ferguson Creek; up to 2.0 darters/m2 in 
slab pools in Big Creek 
1.7 females: 1 male in Ferguson Creek; 1.3 females: 1 male in Big Creek 
3+ years 
72 mm standard length 
To and from spawning grounds 
Extreme in breeding males; weak in females and nonbreeding males 
Aquatic insect immatures and crustaceans 
ee a a eee eee ee 
