Spinicrurellum, Taylor, 2025

Spinicrurellum new genus

Fig. 4d View FIGURE 4

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Type species: Spinicrus nigricans Hickman, 1957 View in CoL .

Etymology: Gender neuter, from the historical genus Spinicrus (currently regarded as a synonym of Megalopsalis ) with the diminutive suffix - ellum.

Description: As for the type and only species ( Hickman 1957; Taylor 2013b).

Comments: This species was included in Megalopsalis by Taylor (2013b) along with other species of ‘ Spinicrus ’, though its distinctive appearance was commented on at the time. Since then, both morphological (see above) and molecular ( Giribet et al. 2021b) phylogenetic analyses have placed M. nigricans in an isolated position from other Megalopsalis species. As such, it is here accorded its own genus.

Spinicrurellum may be readily distinguished from all other Enantiobuninae by its ozopores which are small and circular rather than oblong, and sit flush with the lateral margin of the prosoma rather than being raised on lobes. The genital morphology is also unique, with the penis being remarkably short, broad and flattened, and the glans being shorter than wide and subtrapezoidal ( Fig. 4d View FIGURE 4 ). Major males, though seemingly rare ( Taylor 2013b), have distinct dorsal rows of elongated denticles on the chelicerae that are only paralleled by those seen in Ungoliant photophaga ( Taylor & Probert 2014) .