Minimamichaelia, Uusitalo, 2025

Genus Minimamichaelia gen. nov.

Type species: Michaelia subnuda Berlese, 1910: 201 , fig. 20, Italy, Florence , Boboli, moss .

Differential diagnosis. This genus can be separated from all the other bimichaeliine species by the absence of a primary pattern, i.e. the reticular pattern of roundish to polygonal loops formed by large lamellae is absent; granules and transversely inserted small to medium-sized lamellae are in undulant rows so that the middle-sized lamellae are clumped in culmination points ( Fig. 51C). Other diagnostic features: tiny species; prodorsum holotrichous; dorsum sparsely neotrichous; setae sparsely ciliated; two baculiform solenidia on tarsi I ( Figs. 52E–H, 55, Remarks).

The primary pattern of Bimichaelia Thor forms roundish to subpolygonal loops of large lamellae; and the tiny ridges inside loops are granular; species are small to middle-sized ( Fig. 51A); prodorsum holotrichous; dorsal setae have less than ten, mainly short barbs basally, which are difficult to discern against the intricate cuticular pattern; and usually three baculiform solenidia on tarsi I ( Fig. 52A–D).

Members of Quartusmichaelia gen. nov. have a reticulate pattern of polygonally arranged large lamellae; small lamellae are transversely on ridges inside loops ( Fig. 51D); species are small to middle-sized; ciliated dorsal setae are easily discernible because of several elongated cilia per seta at least on the shoulders and middorsum, but lanceolate setae are common; extra setae, if any, only on soft prodorsum; only one pair of setae in; and one of the two baculiform solenidia on tarsus I is hook-like or S-shaped ( Fig. 53A–H).

Laminamichaelia sensu str. have a reticulate pattern of polygonally arranged large lamellae; small lamellae are transversely on ridges inside loops ( Fig. 51E); species are medium-sized to large; dorsal setae are often bush-like, easily discernible because of several elongated cilia per seta; both in -area and soft prodorsum are neotrichous; and there are usually three baculiform solenidia on tarsi I ( Fig. 53I–L).

Glabromichaelia gen. nov. have integumental ridges that are parallel and without granulae or laminae ( Fig. 51B); its single species is large in size; dorsum neotrichous with elongated and ciliated setae; both soft integument and in -area on prodorsum neotrichous; and two baculiform solenidia on tarsi I ( Fig. 52I–L).

Remarks. The biggest lamellae in the lamellar clumps of subnuda -group of Laminamichaelia sensu lato were mistaken as similar in size as the large lamellae in the lamellar cells of setigera -group, arbusculosa -group and Bimichaelia ( Fig. 52G) in Uusitalo (2010), but in the context with the figures of reticulate integuments, the size of the lamellae rather corresponds with the middle-sized lamellae existing sporadically inside loops of large lamellae in Bimichaelia and the species groups of Laminamichaelia sensu lato ( Figs. 51A–E, 52C, G, K; Uusitalo 2010: figs. 95, 105, 115, 125, 135).

A species of the subnuda -group (now Minimamichaelia ) from South Africa ( Fig. 55) is in the late Prof. Pieter Theron’s Collection and has been temporarily lost in removal of the collection, and the description is unpublished so far (Dr. Edward A. Ueckermann, in litt.). This clade was obtained from the analysis of the family Alycidae as a part of the terminals, which at that time where monotypic, and called by names subnuda -group, along with setigera - group, and arbusculosa -group under Laminamichaelia sensu lato ( Uusitalo 2010). After detailed examination of several species outside Europe it became clear that certain character states are unique to the groups, the groups are no longer monotypic, and the characters are now used in creating generic diagnoses for each of them.

Etymology. The name of the genus is a latinised combination of the Latin word ”minima”, meaning tiny, and “Michael”, referring to the British acarologist Albert Davidson Michael (1836–1927). The name refers to the minute size of the species of the new genus.