Taxonomy

Phylum: Lobopodia

Class: Xenusia

Order: Archonychophora

Family: Luolishaniidae

Genus: Luolishania

Specie: L.longicruris

Description: 

This is one of the most anatomically complex Cambrian lobopodians. As with other Chengjiang lobopodians, the fossils of Luolishania longicruris are preserved in fine‐grained mudstone and are strongly flattened, with some structures retaining a low three‐dimensional relief. Complete specimens are from 8mm to 1.5 cm long. The body is long and slender, divided into a slightly expanded head (from the anterior end to in front of the first pair of lobopods) and a trunk tapering towards the posterior end. The head is round and elongated in dorsoventral aspect, but ellipsoidal in lateral profile, separated from the trunk by a constriction. It is covered by a thin head shield and possesses a pair of antenniform outgrowths in front of a pair of eyes. The eyes are situated dorsolaterally on the head and are suggested to consist of two to three visual units within each eye. The trunk is relatively long and slender, up to 1mm in width. The body tapers slightly towards the posterior end, and there is a small, bluntly rounded projection behind the last pair of lobopods, herein termed the “tail”.  The trunk surface carries fine annulations and setae, except at the areas where the legs and sclerites are attached. Fifteen sets of sclerites are arranged along the body, each set composed of three individual spines arranged transversely (one dorsal and two lateral). One of these sets is on the head, just behind the eyes, with a relatively large basal area and short spine; the others sets are above each pair of legs, with relatively short, thorn‐shaped spines, except the third to fifth sets which are notably longer. Between each set of trunk sclerites, there are three barb‐shaped projections similarly arranged in the middle of each trunk segment. The lateral morphology of the sclerites and their circular traces indicate that the sclerites are thorn-shaped, with a wide base and a slightly curving process. Fourteen to sixteen pairs of legs are situated ventrolaterally beneath the trunk, each possessing setae and four distal claws. The first five pairs of legs are long, slender, covered by dense setae, and with straight, needle‐shaped claws; the other, more posterior legs are much shorter, thicker, less spiny, and with strong, hook‐like claws. Thus the differentiated sclerites, legs, claws, and leg interspaces of L. longicruris define morphologically distinct regions of the body (tagmata): a distinct head and a trunk divided into two sections. The mouth is terminal, leading to a straight and simple gut that extends through the entire length of the body.  The distinct morphological differences in the anterior and posterior legs of L. longicruris indicate a functional difference. Evidence from the gut also indicates that this animal was clearly not a mud eater, but fed on rich organic matter. Based on all available evidence, L. longicruris is suggested to have led a filter‐feeding lifestyle: the stout posterior legs, with strong hook‐shaped claws, help to anchor the posterior part of the body firmly to a suitable medium thus enabling the anterior body with its elongated spiny legs to move around freely in the search for food (possibly organic particles in the water). This species is known from several localities of the Chengjiang biota in Yunnan Province.

Age & Localities

Age: Cambrian Series 2, Stage 3, Eoredlichia-Wutingaspis Zone

Principal localities: Chengjiang biota (Yu’anshan Member of Chiungchussu Formation), eastern Yunnan Province, China