New atyid shrimp from a Western Australian cave 
Paratypes 
Australia: Western Australia: 1 juvenile 2, Karst 
KN-1, Old Napier Downs Cave, 9 June 1966, A. 
Douglas and G. Kendrick (WAM 424-95), 1.79 mm 
CL; 2 <5, 1 2 same collection data as holotype 
(WAM 425-95), 3.00-3.60 mm CL; 1 2 same 
locality as allotype (WAM 426-95), 3.38 mm; 8 
poorly preserved specimens, stn. K10, outer pool. 
Old Napier Cave, 17°14'S 124°41'E, water depth ca. 
1 m, water clear, pH 7.66, substrate mainly 
limestone rock with some loose rocks, gravel and 
sand, outermost pool also with tree roots, water 
temperature 20°C in outermost pool and 28°C in 
innermost pool that could be easily reached, 
outermost and adjacent pools contained shrimps, 3 
July 1988, W.F. Ponder (AM. P.38512); 1 2, same 
data (AM P.40859), 2.9 mm CL; 1 <J, same data 
(AM P.40856, ex P.38512), 1.9 mm CL. 
Diagnosis 
Small atyid shrimp with deep cephalothorax and 
small but well developed eyes; rostrum laterally 
compressed, dorsally and ventrally toothed, lateral 
carina ending before apex; epipods on first four 
pairs of pereiopods; telsonic margin without 
median spine; endopod of first male pleopod 
without appendix interna. 
Description 
Body (Figure la) small, subcylindrical; males in 
collection up to 13.2 mm SL, females up to 15.8 
mm SL. 
Carapace (Figure la) glabrous, depth 0.68-0.9 
CL; rostrum short, 0.37-0.49 CL, length 6.1-6.5 X 
height, curving downward, reaching tip of second 
antennular segment, 11-24 dorsal rostral teeth (x = 
18, s.e. = 1.33), 0-4 (x = 2.6, s.e. = 0.4) situated 
behind posterior orbital margin, setose, 0-4 (x = 
2.7, s.e. = 0.4) ventral rostral teeth; lateral carina 
dividing rostrum into two unequal parts, 
continuing anteriorly from orbital margin to about 
0.7 of rostrum; antennal spine short, strong, placed 
on lower orbital angle; pterygostomian angle 
obtuse, pterygostomian spine absent. 
Eyes (Figure la) small, 0.13-0.20 CL, pyriform, 
corneal diameter 0.45-0.65 X eyestalk length, 
retinal pigmentation present. 
Antennular peduncle (Figure lb) not reaching 
beyond scaphocerite, 0.50-0.60 CL; stylocerite 
length 0.7 X proximal antennular segment length; 
anterolateral angle of proximal segment acute, 
reaching to about 0.27 X intermediate segment 
length; intermediate segment 0.68 X proximal 
segment length, about 1.8 X distal segment length; 
all segments with submarginal plumose setae; 
distal segment fringed laterally and apically with 
plumose setae. 
Antennal peduncle (Figure lc) about 0.5 X 
105 
scaphocerite length; scaphocerite slightly longer 
than antennular peduncle, 0.70 CL, outer margin 
straight to slightly concave, asetose, ending in 
strong subapical spine, length 3.5 X width, 
proximal lamella and interior margin with plumose 
setae. 
Mandibles without palp; right mandible with 
about 6 strong, sharp incisor teeth laterally; 
medially two groups of setae, one group with bent 
hamate setae, other group with finer straight 
plumose setae; molar process ridged; left mandible 
with 6 strong teeth; medially three groups of setae, 
molar process ridged. 
Maxillula with simple palp, slightly expanded 
distally, with long plumose setae distally, few 
simple setae proximally; lower lacinia with broadly 
rounded margin, bearing several rows of plumose 
and simple setae; upper lacinia broadly elongate, 
inner edge straight, with several rows of strong 
spiniform, hamate, denticulate and plumose setae, 
outer and lower inner margins with plumose setae. 
Maxilla with slender tapering palp, shorter than 
upper endite cleft, setose; margin and submargin 
of upper and middle endite with simple, hamate, 
plumose and denticulate setae; lower endite with 
hamate setae; scaphognathite with regular row of 
long plumose setae on distal margin, with shorter 
hamate ones continuing down proximal triangular 
process which has about eleven long simple setae, 
some with prominent dilation at base. 
First maxilliped with broadly triangular lamellar 
palp, ending in pointed tip, margins with plumose 
setae; ultimate and penultimate segments of 
endites indistinctly divided; inner margin of 
ultimate segment with long denticulate setae, long 
rows of plumose, simple and hamate setae 
submarginally, transverse rows of plumose setae 
proximally; exopod flagellum distinct, well 
developed, with submarginal and marginal 
plumose setae; caridean lobe narrow, with 
marginal and submarginal plumose setae. 
Second maxilliped with dactylar and propodal 
segments of endopod fused; inner margins of all 
three proximal segments with long simple, hamate 
and plumose setae; exopod long, narrow with 
marginal long plumose setae distally and shorter 
ones proximally. 
Third maxilliped reaching beyond tip of 
antennular peduncle; endopod three-segmented, 
basal segment length 7.1 X width, with few hamate 
setae on distal outer margin; penultimate segment 
length 8.7 X width, 0.95 X basal segment length, 
with transverse rows of spiniform hamate setae; 
distal segment ca. 0.94 X as long as penultimate 
segment, ending in large claw-like apical hamate 
seta surrounded by simple and plumose ones, 
behind which there are 7-9 hamate setae on distal 
third of posterior margin, clump of serrate and 
pappose setae proximally; exopod reaching about 
