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PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES 
Series 4, Volume 65, 28 Sept. 2018, No. 4 
Figure 4. Argulus floridensis : abdomen; fleshy lobe at Figure 5. Argulus floridensis: first and second antennae, 
posterior of thorax is shown as a dashed outline at anterior of The fleshy segments of the first antennae were obscured or 
abdomen. Setae not shown on caudal rami. Scale bar = 500 missing on this structure but are included as dashed outlines, 
pm. Scale bar = 200 pm. 
1.44 mm [Meehean 1940: 1.35 mm]. Anal sinus length 0.72 mm (720 pm) [Meehean 1940: 0.98 
mm]. Caudal rami paired, long, slender, near base of anal sinus (could not see the setae clearly, usu¬ 
ally there are 5 simple setae at the tip of each). Tips of abdominal lobes narrowly rounded, not 
pointy. Testes extending to level of anal sinus base (Fig. 4). Scales absent on ventral surface of 
abdomen; spines or scales absent along margins of abdominal lobes. 
Mouth tube long, slender, with at least 19 scales on basal half. 
First antennae 4-segmented. First segment (basal segment) sclerotized, large with stout poste¬ 
riorly-projecting posterior spine, narrowly rounded at tip; second segment sclerotized with small 
recurved spine anteriorly with narrow, blunt tip, posteriorly-projecting medial spine with rounded 
tip, and large recurved terminal spine; third and fourth fleshy segments missing or obscured on the 
holotype (Fig. 5). Width of first antennae (mean of both antennae, pm) 530-540 (535) in male. Sec¬ 
ond antennae 5-segmented, fleshy. First two segments larger; remain¬ 
ing three thin, cylindrical; basal segment bears posteriorly-projecting 
posterior spine with narrowly-rounded tip. Postantennal spines single 
(as opposed to double in some taxa), very wide at base, tapering to 
narrowly-rounded tip (Fig. 5). 
First maxillae modified into suction cups in adult. In male, first 
maxillae inner diameter 680 pm and outer diameter 1,050 pm (n = 1). 
Number of sclerites per support rod in male 14-19 (n = 25 support 
rods) [excludes abnormal rods with missing sclerites]. Basal (proxi¬ 
mal) sclerite usually subquadrangular, shape variable; distal sclerites 
imbricate bowls, plates (Fig. 6). Suction cup with 29 sensilla on 
inside circumference. 
Second maxillae 5-segmented with broad basal plate bearing 
three stout spines with the mesial spine broader than the other two 
(Fig. 2). Basal plate with elevated pad bearing 43 scales and one stout FlGURE 6 - Argulus floridensis-. 
. , , , . , , . Two support rods from suction 
seta posteriorly. Bi-dentate to multidentate scales on ventral surfaces cup ( ' right first maxilla ) scale bar 
of segments 2 and 3; segment 4 lacking armature. Distal segment with = ioo pm, 
