Sejus C. L. Koch, 1936

Lekveishvili, Mariam & Klompen, Hans, 2006, New classification of the family Sejidae (Acari: Mesostigmata) based on morphological analyses, Journal of Natural History 40 (41 - 43), pp. 2317-2339 : 2324-2325

Sejus C. L. Koch, 1936

Liroaspis Banks, 1902 (Lindquist and Evans, 1964).

Willmannia Balogh, 1938 (Hirschmann, 1991) .

Diagnosis

Sternal platelets st1 and st 2 in female are not fused (character 55); posterior mesonotal shields in female are not fused to each other.

Species included

Sejus togatus , type species; S. acanthurus Canestrini, 1884 ; S. americana (Banks, 1902) ; S. italicus Berlese, 1916 ; S. paricornis Berlese, 1916 ; S. bicaudus Berlese ; S. insulanus Trägårdh, 1931 ; S. sejiformis (Balogh, 1938) ; S. armatus (Fox, 1947) ; S. baloghi (Athias- Henriot, 1960); S. bakeriarmatus Hirschmann, 1991 ; S. australis ; S. boliviensis ; S. geometricus Hirschmann and Kaczmarek, 1991 ; S. hinangensis ; S. polonicus ; S. posnaniensis ; S. bugrovskii Wisniewski and Hirschmann, 1991 ; S. camerunis ; S. cubanus ; S. mesoafricanus ; S. rafalskii ; S. stebaevi ; S. novaezealandiae ; S. venezuelanus ; S. carolinensis ; n. sp. 3; and n. sp. 4.

Remarks

Balogh separated the genus Willmannia from Sejus based on the absence of posterior projections in adults (immatures are unknown). Since these projections are present in the larva and protonymph of S. posnaniensis , a species which is very close to W. sejiformis (it may even be a synonym), it can be assumed that they are present in the same stages of W. sejiformis as well. The absence of posterior projections in the adults is apomorphic for S. sejiformis and S. posnaniensis , but continued recognition of Willmannia would leave a paraphyletic Sejus .

The species group including Sejus stebaevi , S. americana , S. polonicus , S. togatus , S. hinangensis , and S. rafalskii has characteristic anchor-shaped lateral extensions of the tritosternum in adults; in males the mesonotal and pygidial shields are fused forming an opisthonotal shield (except in S. stebaevi ; male of S. rafalskii is unknown).

The species group including Sejus australis , S. armatus , S. boliviensis , S. venezuelanus , S. carolinensis , S. baloghi , S. camerunis , S. cubanus , and S. mesoafricanus is supported by partially fused ventrianal and posteromarginal shields in the adults, and sickle-shaped lateral extensions of the tritosternum.

Sejus bakeriarmatus is based on a drawing of Liroaspis armatus in a textbook (Baker and Wharton 1952). Validity of this species is unclear.