Friday, January 14, 2022

[Diplopoda • 2021] The Giant Pill-millipede Genus Zephronia Gray, 1832 (Sphaerotheriida, Zephroniidae) from Thailand, with A Redescription of Z. siamensis Hirst, 1907 and Descriptions of Three New Species


 Zephronia golovatchi
Zephronia panhai 
Srisonchai, Sutcharit & Likhitrakarn, 2021


Abstract
Material of the giant pill-millipede genus Zephronia Gray, 1832 recently collected from Thailand contains three new species: Zephronia enghoffi sp. nov., Zephronia golovatchi sp. nov., and Zephronia panhai sp. nov. The first Zephronia species recorded for Thailand, Z. siamensis Hirst, 1907, is also redescribed based on new specimens collected both from the type locality in Chonburi Province and from neighboring areas. Morphological characters of all new species, Z. phrain Likhitrakarn & Golovatch, 2021, and Z. siamensis are illustrated, and a distribution map of the confirmed Zephronia species occurring in Thailand is also provided.

Keywords: Diplopods, key, map, Southeast Asia, taxonomy

Family Zephroniidae Gray, 1843
Subfamily Zephroniinae Gray, 1843

Tribe Zephroniini Jeekel, 2001

Genus Zephronia Gray, 1832
 
Unconfirmed species recorded for Thailand: 
Zephronia cf. viridescens Attems, 1936.

Confirmed species recorded from Thailand: 
Zephronia siamensis Hirst, 1907
Zephronia lannaensis Likhitrakarn & Golovatch, 2021
Zephronia phrain Likhitrakarn & Golovatch, 2021
Zephronia viridisoma Rosenmejer & Wesener, 2021

Photographs of living Zephronia spp.
A, B Zephronia enghoffi sp. nov., paratypes (CUMZ-Zeph0006)
C, D Zephronia golovatchi sp. nov., paratypes (CUMZ-Zeph0008)
E, F Zephronia panhai sp. nov., paratypes (CUMZ-Zeph0010).
Photographs not to scale.

Zephronia enghoffi sp. nov.

Diagnosis: A member of Zephronia s. s. in which the position of Tömösváry’s organ located next to the aberrant ommatidia, not inside the antennal groove. Adult body length medium, > 29 mm, usually ca. 32 mm, up to 36 mm; body brown or dark brown, inner surface (underside) of anal shield with a single locking carina on each side, and leg-pair 2 of male coxa with a long membranous lobe at mesal margin. Similar in these respects to Z. golovatchi sp. nov., but differs from this species by the following combination of characters; antenna short, leg-pair 2 of female coxa apico-mesally with large and conspicuous coxal ridge, operculum of vulva regularly rounded and narrow in posterior view, mesal margin of operculum tapering apically, central margin (tip) of subanal plate shallowly concave, process of telopoditomere 2 of anterior telopod quite long and equal in length to the combination of telopoditomeres 3+4, and immovable finger telopoditomere 2 of posterior telopod (process of telopoditomere 2) equal in length to movable finger (consisting of telopoditomeres 3 and 4).

Etymology: This species is named after Henrik Enghoff from Natural History Museum of Denmark, University of Copenhagen, Denmark, the Danish myriapodologist who initiated an important research step on millipede studies for Thailand.

Distribution and habitats: All specimens were collected from limestone habitats (in dry dipterocarp forest). Known only from three sites in limestone mountain ranges of Khon Kaen and Loei provinces.


C, D Zephronia golovatchi sp. nov., paratypes (CUMZ-Zeph0008)
  E, F Zephronia panhai sp. nov., paratypes (CUMZ-Zeph0010).

Zephronia golovatchi sp. nov.
 
Diagnosis: Adult body length medium to large > 29 mm, usually 35 mm, up to 37 mm; body brown or dark brown, marginal bristles of endotergum extending over posterior margin, inner surface (underside) of anal shield with a single locking carina on each side, and leg-pair 2 of male coxa with membranous lobe at mesal margin. Similar in these respects to Z. enghoffi sp. nov., but differs from this species by the following combination of characters: antenna long; operculum of vulva regularly rounded and broad in posterior view; mesal margin of operculum not tapering apically; central margin (tip) of subanal plate divided by a conspicuous mesal constriction, process of telopoditomere 2 of anterior telopods shorter than telopoditomere 3; telopoditomere 3 of anterior telopods with 2 or 3 crenulated teeth; immovable finger telopoditomere 2 of posterior telopod (process of telopoditomere 2) shorter than movable finger (consisting of telopoditomeres 3 and 4).

Etymology: The species is named for our highly esteemed colleague Sergei I. Golovatch (Zoological Museum, State University of Moscow, Russia), one of the most productive millipede taxonomists, who encouraged all new and young myriapodologists in Thailand.

Distribution and habitats: Known only from the type locality. All specimens have been taken from limestone habitats and were found walking on top of decayed wood or hiding under leaf litter.


Zephronia panhai sp. nov.

Diagnosis: Differs from all congeners by the combination of the following characters; grey body color, adult body length ca. 21 mm, tergites covered by conspicuous setae, long setae on tergites extending over the posterior margin (Figs 13G, 14D), marginal bristles of endotergum not extending over posterior margin, margin of operculum on vulva slightly concave and slightly invaginated medially, telopoditomere 3 of anterior telopods with conspicuous crenulated teeth and telopoditomere 3 of posterior telopods with a row of 11or 12 crenulated teeth.

Etymology: The species name recognizes the great professor and a long-time mentor to the authors, Somsak Panha (Chulalongkorn University Museum of Zoology, Thailand).

Distribution and habitats:. The new species is known from Phetchaburi, Ratchaburi, and Kanchanaburi provinces. All specimens were collected from limestone habitats.


Ruttapon Srisonchai, Chirasak Sutcharit and Natdanai Likhitrakarn. 2021. The Giant Pill-millipede Genus Zephronia Gray, 1832 from Thailand, with A Redescription of Z. siamensis Hirst, 1907 and Descriptions of Three New Species (Diplopoda, Sphaerotheriida, Zephroniidae). ZooKeys. 1067: 19-56. DOI: 10.3897/zookeys.1067.72369