I’m thinking you can only say that because you haven’t taken the time to familiarize yourself with the current state of understanding. Not that I’m particularly familiar with it, but I poke around enough to know they are making incredible finds and interpretations. Here’s a wee sampling:
A Tube-Dwelling Early Cambrian Lobopodian Richard J.Howard, XianguangHou, Gregory D.Edgecombe, TobiasSalge, XiaomeiShi, XiaoyaMasciencedirect _ com/science/article/pii/S0960982220301196
Highlights
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New specimens indicate Facivermis is a tube-dwelling lobopodian
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Phylogenetic analyses place Facivermis in Luolishaniidae (total group Onychophora)
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Facivermis’ worm-like morphology resulted from adaptation to tube dwelling
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Facivermis was not intermediate between cycloneuralian worms and panarthropodsSummary
Facivermis yunnanicus [1, 2] is an enigmatic worm-like animal from the early Cambrian Chengjiang Biota of Yunnan Province, China. It is a small (<10 cm) bilaterian with five pairs of spiny anterior arms, an elongated body, and a swollen posterior end. The unusual morphology of Facivermis has prompted a history of diverse taxonomic interpretations, including among annelids [1, 3], lophophorates [4], and pentastomids [5]. However, in other studies, Facivermis is considered to be more similar to lobopodians [2, 6, 7, 8]—the fossil grade from which modern panarthropods (arthropods, onychophorans, and tardigrades) are derived. In these studies, Facivermis is thought to be intermediate between cycloneuralian worms and lobopodians.Facivermis has therefore been suggested to represent an early endobenthic-epibenthic panarthropod transition [6] and to provide crucial insights into the origin of paired appendages [2]. However, the systematic affinity of Facivermis was poorly supported in a previous phylogeny [6], partially due to incomplete understanding of its morphology.
Therefore, the evolutionary significance of Facivermis remains unresolved. In this study, we re-examine Facivermis from new material and the holotype, leading to the discovery of several new morphological features, such as paired eyes on the head and a dwelling tube. Comprehensive phylogenetic analyses using parsimony, Bayesian inference, and maximum likelihood all support Facivermis as a luolishaniid in a derived position within the onychophoran stem group rather than as a basal panarthropod. In contrast to previous studies, we therefore conclude that Facivermis provides a rare early Cambrian example of secondary loss to accommodate a highly specialized tube-dwelling lifestyle.
Here’s a very cool story about how the march of science works with evidence driving new finds and reinterpretations of old assumptions.
Fossil Focus: Hallucigenia and the evolution of animal body planswww_ ncbi.nlm.nih - gov/pmc/articles/PMC3735267/
Hallucigenia's onychophoran-like claws and the case for TactopodaAuthors: Martin R. Smith and Javier Ortega-Hernandez Date: Oct. 16, 2014
From: Nature(Vol. 514, Issue 7522) Publisher: Nature Publishing Group
The Palaeozoic form-taxon Lobopodia encompasses a diverse range of soft-bodied ‘legged worms’ known from exceptional fossil deposits [1, 2, 3, 4, 5, 6, 7, 8, 9]. Although lobopodians occupy a deep phylogenetic position within Panarthropoda, a shortage of derived characters obscures their evolutionary relationships with extant phyla (Onychophora, Tardigrada and Euarthropoda) [2, 3, 5, 10, 11, 12, 13, 14, 15]. Here we describe a complex feature in the terminal claws of the mid-Cambrian lobopodian Hallucigenia sparsa–their construction from a stack of constituent elements–and demonstrate that equivalent elements make up the jaws and claws of extant Onychophora. A cladistic analysis, informed by developmental data on panarthropod head segmentation, indicates that the stacked sclerite components in these two taxa are homologous–resolving hallucigeniid lobopodians as stem-group onychophorans. The results indicate a sister-group relationship between Tardigrada and Euarthropoda, adding palaeontological support to the neurological [16, 17] and musculoskeletal [18, 19] evidence uniting these disparate clades. These findings elucidate the evolutionary transformations that gave rise to the panarthropod phyla, and expound the lobopodian-like morphology of the ancestral panarthropod.
Palaeozoic lobopodians feature prominently in discussions about the origins of crown-group panarthropods–the extant velvet worms (Onychophora), water bears (Tardigrada) and euarthropods (Euarthropoda) [5, 9, 10, 11, 20]. Although lobopodians have been regarded as onychophoran ancestors [2, 3], the presence of ‘primitive’ characters–such as a terminal radial mouth, unsclerotized annulated cuticle, a non-segmented body and terminal claws in the walking legs–suggests a deeper phylogenetic position [1, 4, 13]. Because lobopodians have few derived morphological features in common with extant panarthropod phyla, there has been much disagreement over the precise affinities of these extinct organisms and their significance for the origins of the major extant groups [5, 10, 11, 12, 14, 20, 21].
Here we describe the fine morphology of exceptionally preserved terminal claws in the Burgess Shale lobopodian H. sparsa (mid-Cambrian; Stage 5), and demonstrate a fundamentally similar construction in the claws and jaws of the extant onychophoran Euperipatoides kanangrensis. These new data clarify both the affinity of ambiguous lobopodians and the evolutionary origins of extant panarthropods. …
Mr. Martin Smith yet again:
Here we describe a complex feature in the terminal claws of the mid-Cambrian lobopodian Hallucigenia sparsa—their construction from a stack of constituent elements—and demonstrate that equivalent elements make up the jaws and claws of extant Onychophora. A cladistic analysis, informed by developmental data on panarthropod head segmentation, indicates that the stacked sclerite components in these two taxa are homologous—resolving hallucigeniid lobopodians as stem-group onychophorans. The results indicate a sister-group relationship between Tardigrada and Euarthropoda, adding palaeontological support to the neurological16,17and musculoskeletal18,19 evidence uniting these disparate clades. These findings elucidate the evolutionary transformations that gave rise to the panarthropod phyla, and expound the lobopodian-like morphology of the ancestral panarthropod.
August 2014 Hallucigenia’s onychophoran-like claws and the case for Tactopodawww _ nature _ com/articles/nature13576