16 
I. Bartsch 
margin of GA truncate; with six pairs of pgs 
(Figure 72). GO large, 142 pm long, 100 pm wide. 
Genital sclerites with five pairs of subgenital setae. 
Spermatheca 30 pm long, 35 pm wide. Gnathosoma 
as illustrated in Figure 73; dorsomedial seta on P-3 
tapering and apically pointed. Tarsus I with 10 pm 
long solenidion between dorsolateral seta and 
lamella with canal from famulus (Figure 74). 
Tarsus II slightly longer than tibia II. Tarsus II 
(Figures 75, 76) with three ventral setae, 8 pm long 
solenidion adjacent to dorsomedial seta, and pair 
of doubled pas. 
Deutonymph 
Idiosoma (Figure 77) 524-603 pm long. OC and 
PD (Figure 79) smaller than plates of adults. Setae 
ds-5 near margin of PD. Quadrangular genital 
plate not fused with anal plate (Figure 80); its 
length 58 pm, width 62 pm; with two pairs of pgs, 
two pairs of subgenital setae and two pairs of 
internal genital acetabula. Anal plate in ventral 
position. Gnathosoma as in female with tapering 
pointed seta on P-3. Chelicera (Figure 78) elongate, 
its claw denticulate. Leg I (Figure 81) with number 
and arrangement of stout spines similar to that of 
adults. Tibiae II, III and IV each with two pairs of 
spine- or seta-like ventral setae. Tarsi I to IV with 
3, 2, 1, 1 ventral setae respectively; tarsus I with 
doubled pas. 
Protonymph 
Idiosoma 410-503 pm long. Outline of dorsal 
plates (Figure 82) similar to that of deutonymph. 
Genital plate (Figure 83) 25 pm long and 35 pm 
wide; with single pair of internal acetabula; pgs 
and subgenital setae lacking. Telofemur, genu and 
tibia I each with pair of long spines (Figure 84). 
Tibiae II-IV each with a single pair of ventral setae. 
Tarsi I-FV with 2, 1, 0, 0 ventral setae. Tarsus I both 
medially and laterally with a large and a small pas. 
Larva 
Idiosoma 251-389 pm long. Frontal spine (Figure 
85) much more slender than that of adults and 
nymphs. PD shorter than in nymphs. Genital plate 
lacking (Figure 86). No spines on femur I; genu 
and tibia I each with pair of spines; tarsus I with 
medial spine (Figure 87). Tibiae II and III each with 
pair of ventral setae. Tarsus II with one ventral 
seta; no ventral seta on tarsus III. Tarsus I, as well 
as the other tarsi, longer than tibiae of the legs. Tip 
of tarsus I medially and laterally each with a large 
and a small parambulacral seta. 
Variations 
In one of the adult specimens, the anterior 
idiosoma is evenly rounded, the others have a 
small frontal spinelet. 
Table 1 Leg chaetotaxy of adult Halacaropsis capuzina 
(solenidia not included; spines in roman 
numerals) 
segment 
1 
2 
3 
4 
5 
6 
leg I 
1 
3 
5-6+III 
7+II 
9+III 
11+1 
leg II 
1 
4 
6-8 
6-8 
9-12 
10 
leg III 
3 
2 
4-5 
4-6 
9-11 
7-8 
leg IV 
3 
2 
4-6 
6-7 
9 
7 
The chaetotaxy of the legs varied and the number 
of setae of four adult specimens is summarized in 
Table 1. 
Remarks 
Halacaropsis capuzina is closely related to H. 
ivarringa (Otto), a species taken on the coast of New 
South Wales, southeastern Australia (Otto 1993). 
Both species are very similar in general facies, both 
have considerably enlarged ds-2, ds-3 and ds-4, the 
outline and chaetotaxy of the legs is almost 
identical. According to the material at hand, viz. 
four specimens of H. capuzina and six specimens of 
H. ivarringa, and the description by Otto (1993), the 
western and the southeastern Australian 
Halacaropsis can be discriminated on the basis of 
the anterior AD - wide rounded lobe terminating 
into a minute frontal spinelet ( H. capuzina ) vs 
trilobed, with two blunt lateral and a spine-like 
median lobe (H. ivarringa) - the ornamentation of 
the cerotegumental layer - smooth in H. capuzina , 
reticulate and with delicate filaments in H. warringa 
- and length of rostrum - as long (H. capuzina) vs 
shorter (H. zoarringa) than width of gnathosoma. 
The seta of P-3 is long, slender and evenly tapering 
at least in females and juveniles of H. capuzina (in 
old specimens it may be broken) but short and 
provided with a truncate spinose tip in both males 
and females of H. ivarringa. 
The genus Halacaropsis includes the species H. 
hirsuta (Trouessart) comb, nov, recorded from the 
Northern Atlantic and the Mediterranean (Viets 
1940; Andre 1946; Chapman 1955), H. ivarringa 
(Otto) comb, nov., taken on the coast of 
southeastern Australia, from coralline algae in 
areas exposed to moderate wave action (Otto 1993) 
and H. capuzina, abundant around Rottnest Island, 
with the adults living amongst the epifauna and 
flora on the seagrass Amphibolis, and the juveniles 
being more widely spread, present also within 
scrub-like corallines. The single Halacaropsis, a 
male, mentioned by Lohmann (1909) from 
Geraldton, Western Australia, differs from the 
specimens from southwestern and southeastern 
Australia in that its rostrum is much longer than 
the gnathosomal base, and the ds-3 are not 
enlarged but similar to the ds-1. 
An undescribed species of the genus Halacaropsis, 
