When Muma (1962) described what is now known as Eremochelis imperialis (Muma 1951),
he placed it into its own unique species group, which he called the
imperialis group. He characterized the
imperialis group as
follows:
Moderate-sized
species. Males with mesal groove of fixed finger an indistinct series
of modified creases and carinae. Apical plumose
bristle of flagellum complex not greatly enlarged or elongated. Ventral
tubular bristles of complex situated in a group in the fondal notch.
Females unknown. Fondal teeth of both rows graded in size I, III, II,
IV.
Muma (1962) subsequently
added what is now known as
Eremochelis rothi (Muma 1962),
which he later Muma (1989) transferred to the
andreasana group.
Rowland (1974) added
Eremochelis kastoni
Rowland 1974, commenting in particular its similarity to
Eremochelis rothi, and raised
his concerns over utilizing the development of the apical plumose bristles
of the flagellum complex in grouping species naturally within the genus.
Rowland suggested that interpreting the relative development of the bristles
in question is not clear cut.
Muma (1989) observed that males of most species seemingly related to Eremochelis imperialis
have the apex of the movable cheliceral finger modified into a more or less
distinct cup, whereas those apparently related to
Eremochelis andreasana (Muma 1962) have the apex of the movable
cheliceral finger flanged at most. He further noted that
imperialis group species have the
apical setae of the flagellum complex serrate, but not especially enlarged.
The taxa included in
the imperialis group as currently
interpreted are:
Eremochelis imperialis (Muma 1951)
Eremochelis kastoni
Rowland 1974
Eremochelis larreae (Muma 1962)
Eremochelis undulus Muma 1989