Halacarines from Rottnest Island 
7 
long, ventromedial one 25 pm. Ventral spine on 1-5 
25 pm long, ventromedial spines, from basal to 
distal, 20, 25 and 17 pm long respectively; the two 
basal spines inserted adjacent. Ventromedial spine 
on 1-6 18 pm long. Spines on succeeding tibiae less 
stout. Tibia II (Figure 27) with two blunt, apically 
dentate ventromedial spines and a ventromedial 
bristle-like seta. Tibiae III and IV each with pair of 
slightly pectinate spines. Tarsus I with short 
membranes of claw fossa, dorsolateral membrane 
with 7 pm long solenidion (Figure 28); tip of tarsus 
with pair of doubled pas. Tarsus II with three 
dorsal setae, a spine-like ventromedial and a seta- 
like ventrolateral pas; solenidion, 8 pm long, 
placed on inner flank of medial membrane of claw 
fossa (Figure 27). Tarsi III and IV each with lateral 
spine-like pas; medially pore of seta but no seta 
present. 
Paired claws of tarsus I with accessory process 
but no pecten. Bidentate median claw with small 
dorsal and rather stout ventral tooth. Paired claws 
on tarsi 1I-III with J-shaped pecten with about 20 
medial tines on the flank and five minute lateral 
tines on the apex of the claw. Median claw present, 
its dorsal tooth absent, ventral tooth very small. 
Male 
Idiosoma 402-433 pm long, GA (Figure 29) of a 
421 pm long paratype 180 pm long, 161 pm wide. 
GO 52 pm long, 34 pm wide, placed within 65 pm 
wide, raised area. Interval between anterior margin 
of GA and that of GO somewhat more than length 
of GO. A pair of outlying setae on level with 
anterior edge of GO and 30-31 pgs on raised area 
close around the GO. Spermatopositor almost 
twice the length of GO, 105-112 pm long, 
extending to 0.05-0.1 relative to length of GA (in 
Figure 29 spermatopositor somewhat dislodged). 
Genital sclerites with four pairs of small spur-like 
subgenital setae. 
Deutonyrnph 
Idiosoma 335—403 pm long. Plates somewhat 
smaller than those of adults. Setae ds-2 inserted in 
membraneous integument anterior to OC (Figure 
30), ds-5 in lateral margin of PD. Genital plate 62 
pm long, 87 pm wide, not fused with anal plate 
(Figure 31). Genital plate with two pairs of pgs and 
two pairs of internal genital acetabula. Telofemur I 
with a ventral and a single ventromedial spine 
(Figure 32); tibia with a ventral and two 
ventromedial spines; setation of genu and tarsus I 
same as that of adults. Setation of tibiae II, III and 
IV same as known for adults. 
Protonymph 
Idiosoma 232-328 pm long (Figure 33). Dorsal 
plates smaller, their outline similar to those of 
deutonyrnph. Alveoli of porose costae 
subrectangular. Genital plate 35 pm long, 50 pm 
wide, with a single pair of internal genital 
acetabula; pgs lacking (Figure 34). Telofemur, genu 
and tibia I each with one ventral and one 
ventromedial spine, tarsus with ventromedial 
spine (Figure 35). Tibia 11 with spine-like, delicately 
bipectinate ventral and short ventromedial seta. 
Setation of tibiae III and IV as in adults. 
Larva 
Idiosoma 232-248 pm long. Dorsal plates (Figure 
36) more delicate than in nymphs. Porose costae of 
AD with three to four alveoli, costae of PD each 
with 12-14 rectangular alveoli. PD and anal plate 
contiguous. Anal plate (Figure 37) larger than in 
nymphs; plate with two spine-like protuberances. 
Except for median areas of AE and AP integument 
of ventral plates rather smooth. No spines on 
telofemur I (Figure 38); genu and tibia each with 
pair of spines; tarsus with ventromedial spine. 
Tibiae II and III each with pair of spine-like setae. 
Variation 
Several specimens have shorter ventromedial 
spines on leg I than has the holotype; in one male, 
e.g., the basalmost spine on 1-3 is 19 pm long, the 
succeeding one 25 pm; the ventromedial spine of 
1-4 is 20 pm long; the spines of 1-5, from basal to 
distal, are 15, 20 and 15 pm, and the spine of 1-6 15 
pm long. 
Remarks 
Agauopsis australiensis is a member of the 
microrhyncha group. The most conspicuous 
character of this group is that tibia I has two of the 
three ventromedial spines inserted adjacent. Until 
now, 17 species have been described. In A. 
australiensis, as in the majority of species, the AD 
has a single frontal spine. A. cryptorhyncha 
(Trouessart), A. felicis Newell, A. filirostris 
MacQuitty, A. itisularis Newell, and A. paulensis 
(Lohmann) are distinguished from these species by 
the tridentate or trilobed anterior AD. A. antarctica 
(Lohmann), A. curvata Krantz and A. glacialis 
Bartsch have a single spine which is bifid, rounded 
or rectangular, but not triangular. A. mokari Otto is 
unique in having four spines on telofemur I. A. 
australiensis is distinguished from the other species 
- A. crassipes (Gimbel), A. humilis Bartsch, A. 
microrhyncha (Trouessart), A. pusilla Viets, A. racki 
Newell, A. robusta Sokolov, A. similis Bartsch, A. 
vinae Newell - by its costae being narrow, one to 
two alveoli wide. 
The species from southwestern Pacific, i.e. A. 
similis, from New Zealand (Bartsch 1979, 1985b), 
and Agauopsis sp., from Australia, Victoria, Philip 
Island - erroneously attributed to A. similis 
(Bartsch 1985b) - and A. australiensis can also be 
distinguished on the basis of insertion of ds-4 
