Diagnosis: This new species seems to be particularly similar to M. siveci Mršić, 1996, with which it shares most of the gonopodal characters. It differs from M. siveci by the wider body, 2.7–3.2 mm (vs smaller, 1.2 mm), the colour pattern which is uniformly red brown with lighter red brown paraterga (Fig. 3A–F) (vs a light brown body with the collum and caudal edges of metazonae margined darker brown; Fig. 1A), as well as the pleurosternal carinae present until segment 11 (vs until segment 5), the sternal lobe between ♂ coxae 4 with a pair of small cones laterally near base (Fig. 3E, H, I) (vs absent, Fig. 1D), and the tip of the gonopod with a denticulate margin (Figs 4A, B, 5C, D) (vs smooth and rounded; Fig. 1E–G).

Etymology: To emphasize “hulutbeeda” which means “flat-back millipede” in Malay dialect, a noun in apposition. A Malay dialect language is mainly used in three provinces of southern Thailand where the holotype was obtained.

Remark: This species was found living together with M. halabala sp. nov. Moreover, according to our observations, they may even occur syntopically, sharing the same habitat: leaf litter surface, branches of trees and tree trunks.

 Natdanai Likhitrakarn, Sergei I. Golovatch and Wisut Sittichaya. 2022. Review of the Millipede Genus Malayorthomorpha Mršić, 1996 (Diplopoda, Polydesmida, Paradoxosomatidae), with Descriptions of Two New Species from Thailand and A Key to its Species. ZooKeys. 1118: 1-19. DOI: 10.3897/zookeys.1118.89593