Timms: A revision of Limnadopsis clam shrimps 
57 
central ones short and stout, but these changing to long, thin 
curved spines on inner edge. Palp of movable finger short 
with hair setae apically. Base of movable finger broad, sup¬ 
porting posteriorly an evenly curved finger terminating in 
a small spine. Palp two-segmented, as long as hand in the 
first clasper and about half as long again in second clasper. 
Distal segment bearing many short hair setae apically. No 
setae on junction of two palp segments. 
Third thoracopod (Fig. 4B) similar in structure to that of 
L. birchii (Fig. 4A). Proportions of endites, endopod, exopod 
and epipodite slightly different, and significantly palp of the 
fifth endite only about half its length. Other thoracopods 
of same basic structure, but without palp and generally 
epipodite larger. 
Telson (Fig. 6C) armed with 11 spines in each row, 
spaced unevenly and of various widths and lengths. Anterior 
spine about three times as large as the others and curving 
slightly posteriorly; posterior spine with posteriormost 3 
telsonic spines on its anterior surface, curved anteriorly 
and more than twice as long as wide at the base. Two 
telsonic setae inserted on protuberance about one third 
of way along dorsal margin of telson. Caudal claws well 
developed, more than twice as large as posterior telsonic 
spine and unevenly curved concavely forward. Basal half 
thick, almost straight, and bearing about 10 shortish hair 
setae mesodorsally. Short spine about two-thirds of way 
along the claw on dorsal surface, followed by row of many 
denticles dorsally on pointed apex of claw. 
There are no females in the original collection by Prof. 
Spencer, so no description of a female L. tatei is available. 
Variability. As noted by Spencer & Hall (1896), the carapace 
of males varies in the shape of its dorsal outline from straight, 
as in the Austin Downs specimens (Fig. 7A) to slightly 
convex as in the neotype (Fig. 6A). Further variability is 
seen in size of adult male carapaces (9-13 mm long), the 
number of growth lines (7-11), and the development of the 
dorsal spines. The latter range from being almost absent, 
as in the specimens from Yalgoo, to well developed as in 
most specimens seen. The male rostrum (Fig. 7B) is often 
relatively longer than in the neotype, reaching twice its basal 
width and the degree of rounding and posterior bending very 
variable. First antennal lobules usually range from 8-10 and 
antennal segments from 12-16; both were often observed 
to be damaged and missing parts. Most specimens have 26 
body segments, but a few have only 25. Major variability in 
the telson (Figs. 6C, 7C,H) includes the number of dorsal 
spines, ranging from 9-13, caudal claw setae varying from 
8-12, and spines varying from 1-3, more often three than the 
one of the neotype. The anteriormost dorsal spine is always 
at least twice the size of other such spines, and often even 
larger, as in the neotype. 
Females are similar to males (Fig. 7F-H), as was first 
noted by Spencer & Hall (1896). They noted that the dorsal 
margin of the carapace is distinctly more convex in the 
female, the rostrum is shorter, and there are fewer lobules 
Fig. 7. Limnadopsis tatei Spencer & Hall, Austin Downs, via Cue, WA. Male: (A) carapace; ( B ) head and antenna 
1; (C) telson; (D) second clasper with some details. Female: (E) carapace; (E) head and antenna 1; (G) telson. Scale 
bars 1 mm. 
