Pacific Symphytognathid Spiders 
B. J. Marples^ 
The family Symphytognathidae was erect- 
ed by Hickman (1931) for a minute spider, 
Symphytognatha globosa, from Tasmania. The 
most characteristic feature is the absence of 
lung-books, the anterior spiracles leading 
into tracheal tubes which supply the cephalo- 
thorax as well as the abdomen, while the 
posterior spiracles are absent. In S. glohosa the 
female has no palps. Page (1937) and Gertsch 
(1941) have transferred several other genera 
into this family, or described new ones. In 
some of these only four eyes are present in- 
stead of the usual six, and the female palps 
may be merely reduced in size instead of ab- 
sent. 
Some of the specimens described in the 
present paper were collected in 1946 in Upolu, 
Western Samoa, during a visit devoted to 
the collection of arachnids; a few hours of 
collecting in Suva, Fiji, on the return journey, 
yielded specimens of a closely related but 
quite distinct species. Because this is a pe- 
culiar and interesting family which has not 
previously been recorded from the Pacific is- 
lands, it seemed desirable to deal with both 
species together. The main Samoan collection 
is being dealt with as a whole. 
In the following descriptions the leg index, 
given below the leg formula, is the length of 
the leg divided by the length of the carapace. 
The tibial index is the breadth of the proximal 
end of the patella expressed as a percentage of 
the combined lengths of the tibia and patella. 
Vatu gen. nov. 
Six eyes. Chelicerae fused for about half of 
^Professor of Zoology, University of Otago, Dune- 
din, New Zealand. Manuscript received, March 28, 
1950. 
their length. Ventral end of the retromargin 
of the cheliceral groove with a large bifurcated 
process. Palp of female absent. Three claws, 
ventral one large. Abdomen pear-shaped with 
ventral spinnerets. Close to genus Symphytog- 
natha^ but different in web and coccoon and 
in a number of minor structural characters. 
Genotype: Vatu vitiensis. 
Vatu vitiensis n. sp. 
Three 9, Icf, 1 immature cf. From tree 
trunks, Suva, Fiji. 
FEMALE: Length 1.20 mm. Carapace, ster- 
num, and mouth parts brown, legs lighter. 
Abdomen mottled greyish-brown above, 
darkening towards the posterior end. Ventral 
surface behind the spinnerets very much 
lighter, almost cream-coloured. 
Carapace: Length 0.37 mm., breadth 0.32 
mm. Highest near the eyes, which are near the 
anterior margin. 
Eyes: Six, all pale. Posterior row recurved. 
Lateral eyes touching. PME separated from 
one another by one quarter of their diameter 
and from the PLE by rather more than their 
diameter. Ratio of eyes PLE : ALE: PME = 
71:68:60. Eye group breadth 0.23 mm. 
Chelicerae: No boss or stridulating organ. 
Apparently fused for rather less than half of 
their length. Fang stout with relatively large 
serrations, and longer than the groove. The 
ventral retromargin of the groove with a 
stout process bifurcated into two blunt teeth. 
Maxillae: Converging but not meeting 
above the lip. 
Lip: Broader than long. 
Sternum: Length 0.23 mm., breadth 0.22 
mm. Convex. 
Valp: No vestige visible even in cleared 
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