Lauravolsella willemeni, Haug & Fraaije & Haug, 2023

Haug, Joachim T., Fraaije, René H. B. & Haug, Carolin, 2023, A new species of possible archipolypodan millipede from the Carboniferous of the Netherlands with unusually long tergites, Comptes Rendus Palevol 22 (29), pp. 595-604 : 597-599

Lauravolsella willemeni n. gen., n. sp.

( Figs 1; 2; 4)

urn:lsid:zoobank.org:act:6554B9A8-E52E-45FA-BD7F-F9F60F67DA68

DERIVATION OF NAME. — After the surname of the collector.

HOLOTYPE. — MAB13859A/B.

TYPE LOCALITY AND AGE. — Coal mine dump of mine “Laura” near Eygelshoven in Southern Limburg, the Netherlands, lowermost Westphalian (Westphalian A).

DIAGNOSIS. — Elongate millipede with 20 diplosegments. Each diplosegment with a posteriorly drawn out diplotergites, three times the length of the ventral region of each diplosegment.

DESCRIPTION

Elongate specimen, longer than wide, at least 4.5 times, total length c. 40 mm ( Figs 1; 2). Mostly ventral details accessible. Subdivision into discrete units apparent: one anterior region, a series of 20 sub-similar units, and a terminal end. The segmented appearance of the body indicates that the specimen is a representative of Euarthropoda; representatives of this group have a body usually differentiated into an anterior head and a posterior trunk.

Anterior region not well preserved with many details, therefore remains partly unclear. It is wider than long. Possibly this region represents the original head region and some trunk segments. The anterior edge of this region is gently rounded, further posterior elevations and depressions may represent remains of original mouthparts. Alternatively, the elevated region ( Fig. 2C marked green) may represent the not well preserved head, and the depression ( Fig. 2C marked cyan) may represent a not well delineated trunk segment. At least one pair of insertion areas of presumably locomotory (ambulatory) appendages is apparent at the posterior part of the anterior region. These are most likely arising from a trunk segment, not well delineated from the rest of the anterior region.

All of the following 20 units are subsimilar in appearance ( Figs 1; 2 A-C). Each unit is wider than long, about four times. Medially a sternal sclerite is apparent, occupying about 20% of the area. The sternal sclerite is deeply subdivided into two equal parts, an anterior one and a posterior one, by a distinct groove ( Fig. 2D). Along the groove, four evenly spaced pores apparent. Adjacent to the sternal sclerites insertion areas of appendages or proximal parts of appendages apparent, two pairs per unit. These insertions/proximal parts are of similar dimensions as an anterior/posterior part of a sternal sclerite. Further laterally smooth region. Far lateral parts of the dorsal region of the unit visible in some of the units. More elongated than ventral region, up to three times.

Further posterior units slightly more slender. Very posterior ones slightly backwards curved, partly surrounding the posterior end.

Terminal end drop-shaped with tip facing backwards, slightly longer than wide ( Fig. 2E). Three distinct sclerites apparent; antero-median sclerite small circular; other sclerites elongate left and right (symmetrically similar), anteriorly surrounding the small sclerite, posteriorly leaving an elongate triangular gap between them.