A new species of Steganacarus (Acari, Cryptostigmata) from Israel B. W. Parry Department of Zoology, British Museum (Natural History), Cromwell Road, London SW7 5BD Introduction In connection with a computer study of phenetic affinity within the Phthiracaroidea, Sheals (1969) examined a small collection of phthiracarid mites collected by Dr M. Costa from bay litter (Laums nobilis) in Upper Galilee, Israel. The material was found to contain several specimens of an undescribed and very distinctive species of the genus Steganacarus Ewing, characterized by the presence of an anterodorsal notogastral pouch. A series of scanning electron micrographs published later by Griffiths & Sheals (1971) illustrated certain aspects of the external morphology of this mite, a description of which is given below. Family PHTHIRACARIDAE Perty, 1841 Steganacarus sacculiferus sp. nov. Aspis (Figs 1-3) : 242-463 jim long and with a greatest width of 206-370 [im. All the dorsal setae are fine, short and procumbent. The interlamellar (//) and lamellar setae (la) are more or less equal in length and form a transverse row behind which the prodorsal integument is raised into a number of longitudinal ridges. The sensillus is membranous, blunt distally and cranked near the base. Three finger-like tracheoles can be discerned below the bothridium and there is a single pair of short exobothridial setae (ex). In front of the il-la row there is a pronounced median keel and a pair of lateral keels. There is a distinct lateral ridge and a pronounced scale behind the bothridium. The aspal rim and the margins of the bothridial apertures are thickened. The integument is coarsely pitted around the bases of the keels and over the rostrum, but elsewhere it is finely punctate. Notogaster (Figs 4 & 5; PI. 1A & C): 535-1800 ^m in length along a line through q to h lt and with a greatest depth of 329-741 [xm. All the setae are short (less than the distance q-^), recurved and finely serrated (PI. 1C). Vestigial/! is located just below h v The deep pouch located antero-dorsally (generally rilled with detritus) is partially overhung by a bilobed cowl which originates from the anterior limit of the notogaster and bears setae (c x ) paraxially (PI. 1 A). The notogastral integument is coarsely pitted posterolaterally, while anteriorly, and mid-dorsally in the area bounded by setae (e^ and (/z x ), the notogaster has no distinct ornamentation. Ano-genital region (Figs 9 & 10; PI. ID): There are four pairs of marginal anal setae (i_ 4 ) and a single pair of adanal setae (ad) located submarginally. The genital setae (gi_ 9 ) are minute and arranged in a pattern of 6 + 3 along the paraxial margins of the genital plates. A single aggenital seta ag is located antiaxially in the genital furrow. The integument of the anal and genital plates is distinctly pitted with the exception of the finely punctate setal-bearing areas.There are three pairs of genital papillae, the two anterior pairs bordering the ovipositor. The latter is trilobed. The ventral lobe is triangular in anterior view (PI. ID) and bears two pairs of setae distally 0/!_ 2 ), while the two laterodorsal lobes (indicated by the arrows in Fig. 10) are larger, compressed laterally and each bear seven setae (T^) antiaxially. The surfaces of the laterodorsal lobes are finely striated. Infracapitulum : This is typically phthiracaroid in form (see for example, Macfarlane & Sheals, 1965). There are three pairs of adoral setae, the anterior pair being brush-like distally and the posterior two pairs weakly serrated. Bull. Br. Mus. nat. Hist. (Zool.) 33 (4): 231-296 Issued 27 April 1978 279
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