Fig 1.
A. Simplified representation of segmentation in mites, showing the segments in order but without any of the hypothesized modifications in shape. B. Interpretation of Weigmann [3]. C. Interpretation of Grandjean [5]. D. Interpretation of Klompen et al. [6] E. The three main body furrows of acariform mites. Roman numerals on the segments represent the segmental scheme commonly used for all arachnids [1]. Blue = proterosoma; yellow = metapodosoma; brown = opisthosoma; grey = neutral (no homologue applied); Pc = precheliceral region (acron); Ch = chelicera; Pa = palp; LI–LIV = legs I–IV; white arrowhead = abjugal furrow; black arrowhead = disjugal furrow; grey arrowhead = sejugal furrow.
Fig 2.
Proteonematalycus wagneri Kethley.
A. Lateral view of female (SEM; FSCA 00030222). B. Lateral view of segments F–AN (SEM; same female as above). C. Lateral view of female, approximately 2 minutes after immersion in PVA (light microscopy; FSCA 00030224). Small white arrowheads point to the dorsolateral borders of coxae III and IV (note that there is slight sagging of the integument over the border of coxa III). White dotted lines delineate the borders of segments PS–AN.
Fig 3.
A. Same model as Fig 1E, but color coded to show that the disjugal furrow intersects the metapodosoma (yellow). B. Opilioacarida, based on Klompen et al. [6]. Roman numerals on the metapodosomal segments represent the segmental scheme commonly used for all arachnids [1]. Blue = proterosoma; yellow = metapodosoma; brown = opisthosoma; black arrowhead = disjugal furrow. Thin black line delineates the border between segments C and D.
Fig 4.
A. The proterosoma (anterolateral view). B. The body of an elongate bodied mite. Roman numerals on the metapodosomal segments represent the segmental scheme commonly used for all arachnids [1]. Blue = proterosoma; yellow = metapodosoma; brown = opisthosoma; PE = precheliceral region—epistomo-labral projection; PO = precheliceral region—ocular (also prodorsum or propeltidium); white dotted line delineates the circumcapitular furrow (boundary between gnathosoma and idiosoma).