incertae sedis

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in·cer·tae se·dis

(in-ser'tē sē'dis),
Of uncertain or doubtful affiliation or doubtful position, said of organisms in taxonomic classifications.
References in periodicals archive ?
As yet uncultured bacteria phylogenetically classified as Prevotella, Lachnospiraceae incertae sedis and unclassified Bacteroidales, Clostridiales and Ruminococcaceae may play a predominant role in ruminal biohydrogenation.
The palaeontologist must occasionally compare shells rather than complete organisms, and runs the risk of conflating a gastropod and a nautilus into a single taxon; but when the fossils themselves are fragmentary the only realistic classification must be incertae sedis.
poecilogyrus and listed it as incertae sedis because Amaral (1944) did not mention the name in his review of that species.
Schuh (1974) sub sequently placed Myrmecoroides, as incertae sedis, within the Orthotylinae, as part of his redefinition of suprageneric groupings within the Miridae, which included the placement of the Pilophorini within the Phylinae.
gracilipes, and, thus, is placed as incertae sedis until further knowledge on the Neotropical Sparassidae fauna is attained.
Oddities to be found include the once almost mythical Sao Tome Grosbeak (Neospiza concolor), a unique forest dwelling Fiscal (Lanius newtoni), the strange Dohrn's Thrush Babbler (Horizorhinus dohrni) for which a tag of incertae sedis is certainly well applied, the world's largest Sunbird (Dreptes thomensis), the Weaver (Ploceus grandis), and the Dwarf Olive Ibis (Bostrychia bocagei).
Due to the fragmentary nature of the new material and paucity of knowledge of Palaeozoic scorpions the material is unidentifiable beyond Scorpiones incertae sedis.
Recently, the type species of Liburnia was established to be Embolophora monoceros Stal, 1855 (Bartlett 2008; ICZN 2010), an African species in the Stenocraninae; a decision which unequivocally placed all New World Liburnia into incertae sedis.
Schuh (2001) examined the male genitalia of Plagiognathus phoradendronae Knight, 1929, concluded that this species should be excluded from Plagiognathus Fieber, and treated it as incertae sedis.
Thus, Trechona adspersa Bertkau 1880 is herein considered a Nemesiidae incertae sedis.
The existing taxonomy, although appearing orderly enough in the catalog, dealt with a group that at once was paraphyletic with numerous species placed in other genera, had a large number of undescribed species, had many named taxa that ultimately were treated as junior synonyms, and included many species that did not belong to the group, some of these being moved to other genera and the remainder placed as incertae sedis in lieu of additional revisionary work.