386 
M.S. Harvey 
Dimensions (pm): body 566/465. 
Remarks 
Piona australica belongs to the variabilis species- 
group as defined by Smith (1976). It appears to be 
widely distributed (Figure 52). See under the 
following species for characters by which P. 
australica and P. marchanti may be distinguished. 
Piona marchanti sp. nov. 
Figures 52, 67-77 
Material Examined 
Holotype 
d, Coonjimba Billabong, Jabiru Mining Camp, 
Northern Territory, Australia, 12°42'S, 132°54'E, 15 
January 1980, R. Marchant (NMV K874; SL). 
Para types 
Australia: Northern Territory: 2d, same data as 
holotype (NMV K875-876, SL, FL); 12, Mudginberri 
Billabong, Jabiru Mining Camp, 12°42'S, 132°54'E, 
14 February 1980, R. Marchant (NMV K877; SL). 
Diagnosis 
Male genital field without deep, central pit; 
female genital field with acetabula lying on small, 
scattered plates. Pedipalpal tibia with stout, distal 
seta. Anterior claw of male tarsus III strongly 
curved, with ventral clawlet. 
Description 
Adult 
Colour (in alcohol) pale yellow. Glandularia: 5 
pairs of dorsoglandularia, 4 pairs of 
lateroglandularia, and 6 pairs of ventroglandularia 
(Figures 67, 69). Dorsum with a single pair of 
dorsalia. Venter (Figure 67, 69): apodemes of coxa I 
very short; suture lines between coxae I and II and 
coxae III and IV present; suture lines between 
coxae III and IV extending antero-laterally. Genital 
region (Figures 68, 70): 5-8 (d), 6-7 (2) pairs of 
acetabula; those of d all lying on acetabular plate, 
acetabula unequal in size, the posterior pair larger 
than remaining pairs; those of 2 lying on small, 
scattered plates. Chelicera not examined. Pedipalp 
(Figures 76, 77): tibia with 2 large disto-ventral 
setiferous tubercles, and with disto-dorsal seta; 
tarsus with 3 disto-dorsal setae. Legs (Figures 71— 
75): d tarsus III with unequal claws, anterior claw 
strongly curved, with curved ventral clawlet, 
posterior claw long and slightly curved (Figure 72); 
d tibia IV modified, with posterior concavity lined 
with several proximal and 2 distal peg-like setae 
(Figures 74-75); legs with swimming setae 
arranged as follows: leg I: d, tibia 1-3, metatarsus 
4-5; 2, tibia 6, metatarsus 9; leg II: d, tibia 2—6, 
metatarsus 5; 2, patella 2, tibia 9, metatarsus 13; leg 
III: d, patella 0-2, tibia 5-6, metatarsus 5; 2, patella 
1, tibia 10, metatarsus 12; leg IV: d, patella 2, tibia 
3, metatarsus 3; 2, patella 1, metatarsus 7, tarsus 4. 
Dimensions (pm), d (2): body 557-614/403-42D 
(896/704); capitulum length 144-149 (179); genital 
field 80-90/194-214 (259/301). Pedipalp: 
trochanter 21-29 (?), femur 105-114 (?), patella 56— 
59 (59), tibia 89-97 (102), tarsus 48-52 (60). Leg I: 
trochanter 61-70 (83), femur 86-104 (115), patella 
100-115 (132), tibia 151-170 (182), metatarsus 166— 
192 (213), tarsus 179-198 (220). Leg III: metatarsus 
172-186, tarsus 125-128. Leg IV: trochanter 113— 
132 (128), femur 80-90 (108), patella 109-125 (161), 
tibia 145-159 (200), metatarsus 162-180 (221), 
tarsus 148-159 (204). 
Remarks 
Piona marchanti belongs to the variabilis species- 
group (Smith 1976), and is most similar to P. 
australica. It differs by possessing a small, curved, 
ventral clawlet on the posterior claw of leg IH 
(Figure 72) which is lacking in P. australica. Females 
of these two species are apparently- 
indistinguishable. Piona marchanti has only been, 
collected from two billabongs in what is now 
Kakadu Natl Park (Figure 52). 
Etymology 
This species is named for Richard Marchant, 
collector of the type specimens. 
Piona murleyi sp. nov. 
Figures 52, 78-89 
Material Examined 
Holotype 
d, swamp in Melaleuca Park, Western Australia, 
Australia, 31°42'S, 115°57'E, 25 August 1987, M.S. 
Harvey, J.D. Blyth (WAM 88/2949; SL). 
Para types 
Australia: Western Australia: 14d, 9$, same 
data as holotype (WAM 88/2950-2955, 2958-2974; 
SL, FL); 10d, 72, same data as holotype (NMV 
K881-882, 892, 878-880, 984-994; SL, FL); 2d, 29, 
same data as holotype (SAM; FL); 2d, 2 2, same 
data as holotype (AN1C; FL); Id, 12, same data as 
holotype (CNC; FI,); Id, 12, same data as holotype 
(DCC; FL); 3d, 59, Lake Pleasant View, 4 km NE. 
of Manypeaks, 34°50'S, 118°11'E, 2 September 1987, 
M.S. Harvey, J.D. Blyth (WAM 88/2975-2982; FL); 
2d, 52, same data (NMV K883-884, 886-890; FL); 
2d, small dam S. of Lake Poorginup, 34°33'S, 
116°44'E, 31 August 1987, M.S. Harvey, J.D. Blyth 
(WAM 88/2956-2957; SL); Id, Loch McNess, 
