| Panlongia Temporal range: | |
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| Panlongia spinosa | |
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| Family: | Incertae sedis |
| Genus: | Panlongia Liu et al., 2006 |
| Species | |
Panlongia was a small-sized marine arthropod. Panlongia lived during the late Lower Cambrian (Botomian) in what is today South China. The genus consists of two species, P. spinosa and P. tetranodus. [1]
Panlongia is a flat, 2 cm (0.8 in) long nektaspid, with an oval-shaped non-calcified exoskeleton. Both the head shield (or cephalon) and the tail shield (or pygidium) are semi-circular. In between the cephalon and pygidium are four thoracic body segments (somites). The cephalon occupies approximately ⅓ of the body length, the thorax ¼ and pygidium about 45%.
In Panlongia spinosa, the edge of the exoskeleton carries several small sawtooth-like spines, that are absent in P. tetranodusa. [1]
The phylogenetic position of Panlongia remained uncertain due to the lack of appendages until 2024, when more well-preserved specimens with appendages narrowed its placement down to as a nektaspid. [2]
Panlongia tetranodusa occurs with the coeloscleritophoran Allonia sp., the vetulicolian Vetulicola gangtoucunensis, lingulate brachiopods Lingulellotreta malongensis, Diandongia pista, Acrothele rara, and Westonia gubaiensis; radiodonts Houcaris saron and Guanshancaris kunmingensis , hyolith Linevitus malongensis, eocrinoid Wudingeocrinus rarus, Trilobites Redlichia yunnanensis , R. mansuyi, R. noetlingi, R. conica, R. shijiangjunensis, Palaeolenus douvillei , and P. lantenoisi; crustaceans: Tuzoia sinensis, T. tylodesa, Branchiocaris sp., Liangshanella liangshanensis, and Neokunmingella sp., and several other arthropods like Longquania bispinosa, Guangweicaris spinatus; Leanchoilia illecebrosa, Isoxys minor and I. wudingensis. [1]