Cruralonga gen. nov.

Type-species.

Cruralonga milnerii sp. nov.

Included species.

C. milnerii sp. nov., C. gracilipes comb. nov. (Womersley 1963 a), C. gracilare comb. nov. (Womersley 1963 b).

Larvae diagnosis.

Scutum with straight anterolateral edges, not concave, edges not concealed by overlapping epicuticle. Anterior region of scutum moderately broad. AL setae longer than AM and PL scutal setae. Long filiform sensilla (90 or greater, up to 168 µm) and bearing only few cilia in distal quarter. Without neotrichy in Cruralonga milnerii and moderate hypertrichy in C. gracilipes (62 dorsal setae). Palps slender, palp genu elongate, more than 1.5 times genu width. Palp tibial claw bifid (and highly reduced in C. milnerii). Basal cheliceral segment long (ca. 90 or more), narrow. Cheliceral blade long, weakly curved. Leg segmentation 7.6. 6. Urstigmata sessile against posterolateral margin of coxa I at least in Nullarbor Cruralonga. Coxa I separated from coxa II by a region of soft epicuticle. Ventral face of coxa I and III with conspicuous foveolate ornamentation. All legs elongate,> 500 µm, slender, with tarsus length to width ratio of 8 to 12 (Table 1). Single claw on all tarsi.

Adult diagnosis.

Idiosoma long and narrow with constriction in sejugal plane (between leg II and III), weak or entirely absent. Idiosoma densely clothed in triradiate (also termed trident) body setae. Median branch of body setae not expanded. Crista long to very long. Posterior projection of crista absent. Sensilla filiform, elongate, with short cilia, mostly in distal quarter, anterior area of crista elongate, spade-shaped bearing three or more pairs of tectal setae along lateral edges. Palp claw simple without accessory setae. Basal cheliceral segment elongate> 240. Cheliceral blade long, weakly curved. Genital region with two elongate oval acetabula. Ventral face of all coxa with foveolate ornamentation. Legs long and slender, tarsus I length to width ratio ranges from 3.3 to 6.9 (Table 2).

Etymology.

Crura is Latin for legs, specifically shanks, and is neuter in gender. The Latin adjective longa means long with feminine gender. As a whole name, Cruralonga is treated as neuter as per the convention with genus names ending in “ - a ”.

Discussion.

For larvae, dorsal setation of Cruralonga spp. is mildly to moderately neotrichous (24–62). Neotrombidium spp. have 40 seta or less, whereas Monunguis is highly neotrichous with an average of 136 dorsal seta. The palp genu of Cruralonga is more elongate (L> 1.5 W) than Monunguis whose length is <1.5 × width. Both Cruralonga and Monunguis, even when unfed, have coxa I and II spaced apart and unlike typical unfed Neotrombidium. Cruralonga and Neotrombidium share 7.6. 6 leg segmentation, whereas Monunguis femur I is not divided (6.6. 6). Legs of Cruralonga larvae are ca. twice the length found in other neotrombidiid larvae. For adults, while the body size of Cruralonga is similar to Neotrombidium spp, the chelicerae, scutal elements, palps and legs are much longer. Previously the ornamentation on coxae, here described as foveolate, has been referred to as mosaic-screened porosity (Lindquist and Vercammen-Grandjean 1971). This phrase is appealing and conveys unusual microsculpturing but the concept of a mosaic screen in this context may not be understood. Foveolate is suggested as a possible alternative, admitting that this ornamentation is less regular than standard examples of foveolate cuticle in entomology and botany.