Wednesday, August 17, 2022

[Diplopoda • 2022] Malayorthomorpha halabala & M. hulutbeeda • 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


Malayorthomorpha halabala
Likhitrakarn, Golovatch & Sittichaya, 2022

กิ้งกือตะเข็บฮาลาบาลา  ||  DOI: 10.3897/zookeys.1118.89593

Abstract
The millipede genus Malayorthomorpha Mršić, 1996, so far monospecific and previously known only from Park Belum, Perak State, northern Malaysia, is recorded from a mountain in Betong District, Yala Province, southern Thailand for the first time, being represented there by two new species: M. halabala sp. nov. and M. hulutbeeda sp. nov. Both new species are found to occur syntopically and can be assumed as narrowly endemic to the Titiwangsa Mountain Range which begins in southern Thailand, crosses the Malaysian border, and extends into east and west coast regions of the Malay Peninsula. In addition, the generic diagnosis is slightly updated, and a key to all three species is provided.

Keywords: Malaysia, Malayorthomorpha halabala sp. nov., Malayorthomorpha hulutbeeda sp. nov., Orthomorphini, taxonomy

Family Paradoxosomatidae Daday, 1889
Subfamily Paradoxosomatinae Daday, 1889

Tribe Orthomorphini Brölemann, 1916

Genus Malayorthomorpha Mršić, 1996

Malayorthomorpha halabala sp. nov., ♂ holotype
A, B anterior part of body, dorsal and lateral views, respectively C, D segments 10 and 11, dorsal and lateral views, respectively E–G posterior part of body, lateral, dorsal and subventral views, respectively H, I sternal cones between coxae 4, subcaudal and sublateral views, respectively.

Habitat at the type locality of Malayorthomorpha halabala sp. nov., ♀
A live colouration B, C elfin montane forest floor and collecting the specimens
B, C pictures taken not to scale.   

 Malayorthomorpha halabala sp. nov. 
 
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 Hala-Bala Wildlife Sanctuary, the type locality. Noun in apposition.


Malayorthomorpha hulutbeeda sp. nov., ♂ holotype
A, B anterior part of body, dorsal and lateral views, respectively C, D segments 10 and 11, dorsal and lateral views, respectively E–G posterior part of body, lateral, dorsal and subventral views, respectively H, I sternal cones between coxae 4, subcaudal and sublateral views, respectively

 Malayorthomorpha hulutbeeda sp. nov.
 
Diagnosis: This new species is distinguished from its two congeners in sternal process between male coxae 4 linguiform with a rounded tip, and lamina lateralis of gonopodal solenophore triangular, apically bifid and protruded laterally.

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

1. 𝑀𝑎𝑙𝑎𝑦𝑜𝑟𝑡ℎ𝑜𝑚𝑜𝑟𝑝ℎ𝑎 ℎ𝑎𝑙𝑎𝑏𝑎𝑙𝑎 Likhitrakarn, Golovatch & Sittichaya, 2022 
กิ้งกือตะเข็บฮาลาบาลา 
ตั้งชื่อตามพื้นที่เขตรักษาพันธุ์สัตว์ป่าฮาลา-บาลา ซึ่งเป็นผืนป่าที่ค้นพบกิ้งกือชนิดนี้ 

2. 𝑀𝑎𝑙𝑎𝑦𝑜𝑟𝑡ℎ𝑜𝑚𝑜𝑟𝑝ℎ𝑎 ℎ𝑢𝑙𝑢𝑡𝑏𝑒𝑒𝑑𝑎 Likhitrakarn, Golovatch & Sittichaya, 2022 
กิ้งกือตะเข็บฮาลุตบีดา 
โดยคำว่า "hulutbeeda" เป็นภาษาท้องถิ่นที่แปลว่ากิ้งกือตะเข็บ