The two species were originally deemed close relatives based on their physical similarities, but several cladistic analyses published since 1998 have suggested the genus may be polyphyletic.

A carnivore like all mantis shrimps, Bairdops handled food with its raptorial thoracic appendages and has been proposed to either predominantly be a scavenger or a predator of crustaceans and small fish.

Its preferred habitat appears to be marine since most of its specimens originate from such a setting, and it only lived in the aforementioned lake when the water was brackish, disappearing from it after its salinity dropped below the animal's tolerance range.

B. beargulchensis is only known to have inhabited the marine bay where the Bear Gulch Limestone was deposited, a location which was 10 to 12 degrees north of the equator and had a monsoon climate.

The generic name honors William Baird, the Assistant Curator of the fossil invertebrate collection at the Royal Scottish museum.

Though Schram and Horner (1978) claimed the propodi of B. beargulchensis possessed two rows of spines, this observation was based on specimens now reassigned to Daidal acanthocercus.

[7] As cladistic analysis became more widely conducted, the palaeostomatopods were first recovered to be a paraphyletic grouping by Jenner et al. (1998), and this paraphyly was then confirmed by Schram (2007).

[10] Smith et al. (2023) conducted a phylogenetic analysis which also supports the idea that Bairdops is polyphyletic, though the family Perimecturidae was found to be monophyletic.

Archaeocaris vermiformis Archaeocaris graffhami †Bairdops elegans Perimecturus parki Perimecturus rapax †Bairdops beargulchensis †Daidal pattoni †Daidal schoellmanni †Daidal acanthocercus Gorgonophontes fraiponti Gorgonophontes peleron †Chabardella spinosa †Tyrannophontes theridion †Tyrannophontes gigantion †Triassosculda ahyongi †Tyrannosculda laurae †Pseudosculda laevis †Archaeosculda phoenicia †Sculda pennata †Sculda syriaca †Ursquilla yehoachi †Lysiosquilla nkporoensis †Nodosculda fisherorum Squilla mantis

[12] Unlike modern mantis shrimps of the suborder Unipeltata, the raptorial appendages of palaeostomatopods like Bairdops lack a click-joint mechanism formed by a specialized joint and its associated muscles.

Such a mechanism is what allows modern mantis shrimps to quickly extend the second pair of thoracic appendages to capture prey.

[14] This is unlike modern mantis shrimp, which are bottom-dwelling predators as adults, though their larvae are benthopelagic and thus studying them could allow better knowledge of early stomatopods.

[16] The geologically oldest known record of Bairdops is represented by remains of B. elegans from the lower part of the Foulden Fish Bed, a site within the Ballagan Formation in Scotland.

[6] This locality dates to the Dinantian series, and the lack of definitively marine species in its fossil content suggests the Foulden Fish Bed was a non-marine lake at the time of deposition.

It was likely extirpated from this area when the water level rose, lowering the salinity beyond its range of tolerance and allowing fish which preyed on it to invade, and failed to recolonize the lake the way Belotelson did.

[16] The Granton Shrimp Bed has one of the most diverse Dinantian fossil assemblages of crustaceans in Britain, and has been interpreted to represent periodically exposed mudflats at a low water stand of a lagoon.

The most abundant crustacean at the Granton Shrimp Bed is Waterstonella, a small swimming species which has been proposed to be a prey item for Bairdops.

Bairdops is deemed a common crustacean in this area, as are Belotelson, Anthracocaris, Perimecturus and Anthracophausia, while Crangopsis, Pseudotealliocaris and Sairocaris are even more abundant than the aforementioned taxa.

[19] The species Bairdops beargulchensis is known only from the Bear Gulch Limestone of Montana, which dates to the Serpukhovian stage of the early Carboniferous period, approximately 324 million years ago.

[20] An extremely diverse fossil assemblage is known from this site, with numerous types of fish including chondrichthyans (such as petalodonts, holocephalans, symmoriiforms, squatinactids and Thrinacodus), acanthodians, actinopterygians and coelacanths.