lives in bee nests and probably disperses on bees, but feeding behavior is unknown
Female: based on the presence of single dorsal shield (Fig. 1), ovipore covered by paired latigynal shields and unpaired mesogynal shield (Fig. 2) and the absence of ambulacra (including claws and pulvillus) on tarsi I (Fig. 2), it belongs to the infraorder Antennophorina, suborder Trigynaspida.
Female: Additional character states separate this genus from other genera in Antennophorina: 4-5 pairs of setae on latigynal shields (Fig. 2), mesogynal shield truncated anteriorly (Fig. 2), dorsal shield and ventral opisthosoma hypertrichous (Figs. 1,2), anal shield on large ventral plate (Fig. 2).
Female: Placement of this genus in a family is unsettled. Celaenosthanus was originally placed in the family Antennophoridae (Vitzthum, 1930). Later, in a revision of Trigynaspida, it has been suggested that Celaenosthanus represents either a separate subfamily in the family Diplogyniidae, a family in the superfamily Celaenopsoidea, or a family outside Celaenopsoidea (Kethley, 1977). The following diagnostic characters separating Celaenosthanus from other Celaenopsoidea were cited: the vaginal sclerites, although rather large, are membranous, the leg chaetotaxy is much richer than any known celaenopsoid species, the chelicerae are somewhat reduced, the metapodal sclerotization is completely separate from the ventrianal sclerotization, legs I are antenniform, and the peritreme is laterally hypertrophied. Many of these diagnostic character states were scored by Kethley from actual specimens (not available to us).
No dichotomous key is available. This genus contains one described and two undescribed species (Kethley, 1977).
associated exclusively with bees or their close relative, wasps; cannot live without these hosts
some life stages are associated with bees, while others are not
can complete entire life cycle without bees or their close relative, wasps
All three known species of Celaenosthanus are associated with Trigona and have not been found elsewhere, indicating that species of this genus form permanent associations with their hosts. Celaenosthanus trigonophilus has been found in the nest of Trigona fuscipennis, but specific location (nest or phoresy on adult bee) has not been reported for the remaining two species (Kethley, 1977). Other aspects of the biology of Celaenosthanus are unknown.