taxonID	type	description	language	source
03AB2952FFEC5E500FBDFE13FDAC0D5F.taxon	type_taxon	Type species: Unixenus padmanabhai (Jones, 1937)	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFEC5E500FBDFE13FDAC0D5F.taxon	diagnosis	Diagnosis. Body with 10 segments, 9 pleural projections and a telson, 13 pairs of legs. Eight ommatidia in each eye; 8 antennal articles with the article VI longest and the article VIII shortest with 4 sensory cones present. Antennal article VI commonly with 1 setiform sensillum between 2 thick bacilliform sensilla, and 1 conical sensillum posteriorly. Anterior surface of labrum covered with spherical papillae gradually reducing in size posteriorly. Lateral palp of gnathochilarium 1.5 – 2.5 times longer than medial palp, 20 – 22 sensilla on medial palp and 13 on lateral palp. Two or more rows of tergal trichomes arranged in two latero-posterior clusters either side of the midline, with a central gap. Anterior row often uneven, intermediate rows rarely in defined rows and posterior row of trichomes continuous or with a medial gap. Tarsus 2 with a setiform seta. A single caudal bundle containing caudal trichomes with 1 – 11 hooks.	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFEC5E5B0FBDFB89FC930C1C.taxon	description	(Fig. 2)	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFEC5E5B0FBDFB89FC930C1C.taxon	materials_examined	Holotype. Male, Tranh River shore (Cua Lap hamlet, Duong To commune, Phu Quoc Island, Vietnam), 10 ° 10 ' 22.82 " N, 103 ° 58 ' 08.14 " E; elevation 5 m; the specimen was collected by the first author from within the stem of a creeping grass (Poaceae) (Fig. 3) growing within the intertidal zone on the beach; on 1 st July, 2015. Queensland Museum accession number: QMS 108520 (deposited in Queensland Museum, Brisbane, Australia). Paratypes. 4 males and 6 females were collected in the same place and on the same date as the holotype. Queensland Museum accession numbers of 10 paratypes: QMS 108521 – 108530 (deposited in Queensland Museum, Brisbane, Australia).	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFEC5E5B0FBDFB89FC930C1C.taxon	etymology	Etymology. The species is named intragramineus, noun in apposition, as it was found living in the stem of a creeping grass growing in the intertidal zone.	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFEC5E5B0FBDFB89FC930C1C.taxon	diagnosis	Diagnosis. U. intragramineus sp. n. has the general characteristics of Unixenus and it shares most characters with U. mjoebergi. Chaetotaxy: one seta present on prefemur and two setae on femur, a single seta on tibia and tarsus 2. The claw of U. intragramineus sp. n. is different from that of U. mjoebergi in being slender, with a posterior lateral process longer by half the length of the claw. A small anterior lateral process is present, anterior setiform process longer than the claw and with enlarged base.	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFEC5E5B0FBDFB89FC930C1C.taxon	description	Description. Measurements: Holotype male body length 1.7 mm, males (paratypes) ranging from 1.7 – 2.0 mm (n = 10) and females (n = 10) from 2.2 – 2.5 mm. Caudal bundle of male slightly narrower in width and longer (0.6 mm) compared to female caudal bundle, the latter wider and shorter (0.5 mm). Colouration: Head dark brown in eye area connected to 2 brown transverse bands in vertex area. Body milky white in colour, contrasting with light brown pleural trichomes and darker colour in caudal bundle; dark brown marks on latero-posterior rosette trichomes forming a dark band along each side of body laterally; last tergite darkest in colour. Ventral side of body white in colour (Fig. 2). Head: 8 ommatidia on each side: 4 dorsal, 4 lateral (1 anterior, 2 medial and 1 posterior). Vertex with 2 posterior trichome groups and a large gap between them, each group with 2 rows. Anterior, oblique row with trichome sockets of similar size. Posterior row with slightly smaller trichome sockets. A narrow space between anterior and posterior rows (Figs 4 A and 5 A). Holotype with 13 + 13 trichome sockets in anterior row and 7 + 7 trichome sockets in posterior one. Paratypes with variations common in this species regardless of sex, from 10 – 16 (anterior rows) and 5 – 8 (posterior rows). Trichobothria: trichobothrium a (posterior position) and trichobothrium b (lateral position) typically thin sensory hairs with narrow cylindrical funicles; trichobothrium c (anterior position) similar in structure to trichobothria a and b, but its funicle slightly enlarged distally. All these trichobothria (a, b and c) equal in socket size and forming an isosceles triangle with equal distance between ab and bc (Figs 4 E and 5 B). Antennae: 8 articles and 4 sensory cones (Fig. 6 A), characteristics typical of Polyxenidae. Antennal article VI with 3 thick bacilliform sensilla (T) of different lengths: a short sensillum anteriorly (T 1), the longest intermediate sensillum (T 2), and a sensillum of medium length (T 3). A setiform sensillum (s) present between T 1 and T 2, and a conical sensillum posteriorly (c) (Fig. 6 C). Antennal article VII with 2 thick bacilliform sensilla (T), anterior one being slightly longer than the one located posteriorly, with one setiform sensillum (s) between them and a conical sensillum (c) located in posterior position (Fig. 6 B). This pattern of sensilla on the antennal article VII is commonly seen in all Unixenus species. Clypeolabrum: Holotype with 10 setae at posterior margin, these setae being half the width of labrum. Setae in paratypes ranging from 10 – 15 in both sexes. Labral surface with spherical papillae with pointed ends, reduced in size posteriorly. Anterior margin of labrum with 4 + 4 lamellae on each side of median cleft (Figs 4 G and 5 C, D). Lateral palp of gnathochilarium: Lateral palp 2.5 times as long as medial palp. 13 conical sensilla on lateral palp, medial palp with 22 slender conical sensilla observed in all paratypes and holotype (Fig. 4 F). Trunk: Body with 10 segments, 9 pleural projections, excluding both telson and caudal bundle; 13 pairs of legs. Collum (tergite 1, smallest) with trichome sockets arranged in 2 oval shapes laterally, opposite each other connected by a posterior row of trichome sockets forming a line with a gap in middle. Collum, a tergite only with lateral protuberances, bearing a small number of trichome sockets. In holotype, collum with 46 (L) or 48 (R) trichome sockets, lateral protuberances with 5 trichome sockets on each side (Fig. 4 B). Trichome sockets on collum varying in paratypes and ranging from 42 – 60, trichome sockets ranging from 4 – 7 on lateral protuberances. All other tergites, from 2 to 10, each with a pair of pleural projections located anterolaterally. Tergal trichome socket arrangements from tergites 2 to 9 typically with 4 undefined rows of tergal trichomes arranged in two lateroposterior clusters, either side of midline. Anterior row often uneven, intermediate rows rarely in defined rows and posterior row of trichomes continuous and evenly distributed, forming a line with a medial gap. Tergite 10 exceptional in trichome sockets being smaller and denser. Almost no space between lateral rosette trichome sockets and those in posterior row. Trichome sockets of tergite 2 in holotype numbered 52 (L) and 54 (R) (Fig. 4 C), tergite 10 with 50 (L) and 49 (R) (Fig. 4 D). In contrast, trichome sockets on tergite 2 in paratypes ranging from 46 – 67, whereas tergite 10 containing between 53 – 66 trichome sockets. Legs: Leg segments are named following Manton (1956). Legs 1 and 2 without trochanter, leg 1 lacking tarsus 1 as well. Chaetotaxy: coxa 1: 2 setae, coxa 2: 2 setae, coxae 3 – 13: 3 – 4 setae; prefemur, tibia and tarsus 2 with 1 seta; femur with 2 setae (Fig. 7 A). Setae on coxa and prefemur, and at distal edge of femur: bi-articulated with longitudinal ridges on basal funicle, each ridge extending distally into a long and thin spine, with the spines surrounding a base of flagellum (Fig. 7 B); seta of mid femur similar, but smaller (Fig. 7 C), tibia and tarsus 2 each with a setiform seta (Figs 7 D and 7 E). Posterior edge of last sternite with 2 – 4 setae similar to those present on coxa, number of these setae varying; two present in holotype and 2 – 4 in paratypes. Sex organs in male: A pair of penes present on coxae 2 and 2 pairs of coxal glands located on coxal plates of legs 8 and 9. Telotarsus-Claw: A slender structure bearing a posterior process, the latter longer by half the length of claw. Both a small anterior lateral process and a lamella process present, anterior setiform process enlarged at base and longer than the claw (Fig. 7 F). Telson: Dorsal ornamental trichome sockets arranged symmetrically with 4 sockets of trichomes a in holotype; paratypes with 5 – 7 sockets of trichomes a. A single trichome b and 3 large protruding base sockets of trichome c: c 1, c 2 and c 3, forming a triangular shape, on each side of telson. Circular indentation d apparent near exterior side of trichomes c (Fig. 7 G). Caudal bundles: In males, caudal bundle comprised of a group of caudal trichome sockets forming a single structure of uniform size; this structure split ventrally with trichome socket-free tissue and extending towards the centre with a small gap dorsally. Three rows of the largest sockets of barbate trichomes forming slightly uneven lateral rows, the latter extending towards the centre of caudal structure (Fig. 5 E). In females, caudal bundle different from those in males, with two obvious distinguishing features: caudal bundle structure, the main dorsal structure similar to that of male, and 2 laterosternal bundle structures with smaller sockets of nest trichomes. These smaller sockets located internally and surrounded by 2 rows of caudal trichome sockets externally. Trichome socket-free tissue present ventrally, extending with a small gap and connecting to central tissue where some barbate trichome sockets present. No separation between caudal and nest trichome sockets, all fused into a unified structure of a single caudal bundle structure (Fig. 5 F). Arrangement of caudal bundle of U. intragramineus sp. n. similar in structure to that observed in U. broelemanni (Condé and Nguyen Duy-Jacquemin, 1992), classified as type II.	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFEC5E5B0FBDFB89FC930C1C.taxon	discussion	Remarks. Unixenus species show very similar taxonomically important morphological characteristics: the number of sensilla on antennal article VI, the structure of the gnathochilarium and the chaetotaxy. Caudal bundle type II is common to the genus Unixenus, as well as in other genera in the subfamily Monographinae (Condé and Nguyen Duy-Jacquemin 2008). If only these characteristics are used for identification, it can be difficult to confidently identify Unixenus specimens to the species level. The telotarsus has proved to be a useful additional structure that can help distinguish between species in this genus. Unixenus intragramineus sp. n. has characteristics that are very similar to those of U. mjoebergi; both species have the same chaetotaxy which makes separating these species difficult. However, the structure of the telotarsus in these two species differs. U. mjoebergi has a robust claw, while the claw of U. intragramineus sp. n. is a slender structure. U. intragramineus sp. n. is the only penicillate millipede found living within a grass stem, which is a highly specialized habitat that provides a food source and a refuge from the intermittent tidal inundation.	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFE45E580FBDFE4CFBF20D5E.taxon	type_taxon	Type species: Monographis kraepelini Attems 1907	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFE45E580FBDFE4CFBF20D5E.taxon	diagnosis	Diagnosis. Body with 10 segments, 9 pleural projections and a telson; 13 pairs of legs; eight ommatidia in each eye; 8 antennal articles with the VI longest and the VIII shortest article with 4 sensory cones present. Antennal article VI commonly with 3 – 5 thick bacilliform sensilla positioned amongst 12 – 20 sensilla, arranged in either (1) a simple crescent-shape with anterior sensilla longer than posterior ones (M. kraepelini, M. annandalei, M. demangei and M. mira and M. baihualingensis) or (2) forming a triangular shaped (M. tamoyoensis, M. yunnanensis, M. queenslandica and M. dongnaiensis). A row of minute backward-pointing setae present along posterior margin of labrum. Anterior margin of the labrum with acute triangular shaped setae (found in M. kraepelini) or slender setae, either covering its full length (found in M. kraepelini, demangei and M. baihualingensis), located only near the median cleft (found in M. mira) or totally absent (in case of M. tamoyoensis). Lateral palp of gnathochilarium 1.25 or 1.5 times longer than medial palp and with 9 – 11 conical sensilla. Tergal trichomes arranged in two lateroposterior groups connected by a marginal row, with a central gap. A strong spine present on tarsus 2, another spine being shorter and smaller on tarsus 1. Coxal glands present on the 8 th and 9 th coxa.	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFE45E5D0FBDFB8AFD8F0B51.taxon	description	(Fig. 8)	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFE45E5D0FBDFB8AFD8F0B51.taxon	materials_examined	Holotype. Male, Monographis phuquocensis sp. n. was collected by the first author from leaf litter near Tranh Stream (Suoi Tranh), 10 ° 10 ' 58.96 " N, 104 ° 0 ' 54.72 " E; elevation 86 m; 7 km southeast of the main town - Duong Dong town on Phu Quoc Island on 2 nd July 2015. Queensland Museum accession number: QMS 108531 (deposited in Queensland Museum, Brisbane, Australia). Paratypes. Twelve specimens were collected: 3 adult males, 5 adult females (adult stage- stadium VIII, 13 pairs of legs), and 4 sub-adults (stadium VII, 12 pairs of legs). At the second location: Da Ban Stream (Suoi Da Ban), 10 ° 14 ' 42.36 " N, 104 ° 01 ' 48.82 " E, elevation 43 m; 10 km northeast of Duong Dong town on Phu Quoc Island on 3 rd July 2015; 5 specimens were collected: 2 males and 3 females. Both locations are in the Ham Ninh Mountains on Phu Quoc Island (Fig. 1). Queensland Museum accession numbers for 17 paratypes: QMS 108532 – 108548 (deposited in Queensland Museum, Brisbane, Australia).	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFE45E5D0FBDFB8AFD8F0B51.taxon	etymology	Etymology. The specific name phuquocensis, noun in apposition, refers to Phu Quoc Island in southwest Vietnam, where this species was first found.	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFE45E5D0FBDFB8AFD8F0B51.taxon	diagnosis	Diagnosis. Colour and trichome patterns of Monographis phuquocensis sp. n. similar in appearance to other described Monographis species including M. queenslandica and M. dongnaiensis (Huynh and Veenstra, 2013, 2015). Characteristics and arrangement of caudal bundles are quite similar among Monographis species (Huynh and Veenstra 2015) and this is classified as the caudal bundle type II arrangement (Condé and Nguyen Duy- Jacquemin, 2008) Pattern of sensilla on antennal article VII common to all species of Monographis (Huynh and Veenstra 2013, 2015). M. phuquocensis sp. n. different from other Monographis species in antennal article VI having 15 – 20 sensilla of various sizes, forming a crescent-shape with the anterior sensilla longer than posterior ones. These sensilla form 4 distinct groups: 3 thick bacilliform sensilla commonly present in a group of 2 – 4 thin bacilliform sensilla located anteriorly (Group 1), 2 – 3 medium length thin bacilliform sensilla (Group 2), 1 – 2 short thin bacilliform sensilla (Group 3), and a group of 6 – 8 thick short conical sensilla located posteriorly (Group 4). Surface of labrum asetose and smooth, with a row of setae present near anterior edge of lamellae. Telotarsus bearing a posterior process shorter, half the length of claw. Anterior lateral process and lamella process present; setiform process half the length of claw.	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFE45E5D0FBDFB8AFD8F0B51.taxon	description	Description. Measurements: Holotype male body length 2.0 mm; (paratypes) males ranging from 1.4 – 2.0 mm (n = 5) and females (n = 8) ranging from 2.2 – 2.5 mm. Caudal bundle in male slightly narrower in width and shorter (0.5 mm) compared to female, the latter wider and longer (0.6 mm). Colouration: Body yellowish-brown in colour with 2 darker lateral bands, caudal bundle black-silvery colour (Fig. 8). Head: Eight ommatidia on each side: 4 dorsal, 4 lateral (1 anterior, 2 medial and 1 posterior). Vertex with 2 posterior trichome groups comprised of 2 rows, with a large gap present between these groups. Anterior, oblique with a variable number of large trichome sockets in centre, gradually reducing in size toward both ends; posterior row with slightly smaller trichome sockets. A narrow space present between anterior and posterior rows. Holotype male with 11 + 12 trichome sockets in anterior rows and 2 + 2 trichome sockets in posterior rows (Fig. 9 A). Paratypes with variation common in this species regardless of sex, ranging from 11 – 15 (anterior rows) and 2 – 3 (posterior rows). Trichobothria (trichobothrium a, posterior position, trichobothrium b, lateral position and trichobothrium c, anterior position) typically thin sensory hairs with narrow cylindrical funicles. All these trichobothria (a, b and c) equal in socket size and form an isosceles triangle with an equal distance between ab and bc (Fig. 9 F). Antennae: Eight articles and 4 sensory cones present, characteristics typical of Polyxenidae. Antennal article VI (Figs 10 A and 11 A) with 18 – 20 sensilla. Holotype with 20 sensilla forming a crescent-shape with anterior sensilla longer than posterior ones. These sensilla forming 4 groups: Group 1 located anteriorly with 3 thick bacilliform sensilla (Tbs a, i and p) among 4 thin bacilliform sensilla (tbs), this group followed by a conical sensillum (c); Group 2 with 3 medium length thin bacilliform sensilla (tbs m); Group 3 with 2 short, thin bacilliform sensilla (tbs s); a small gap present between Groups 2 and 3; last group has 8 thick short conical sensilla (Ts c) located posteriorly (Figure 10 C). Different arrangements of sensilla apparent in scanning electron microscope images of other specimens (Figs 11 A, B and C). Antennal article VII with 2 thick bacilliform sensilla (Tbs) with a setiform sensillum (s) between them and a conical sensillum (c) located posteriorly (Figs 10 B and 11 A). Clypeo-labrum: Holotype with 10 setae present on posterior margin, these setae shorter than half the width of labrum. Setae on paratypes ranging from 8 – 11 in both sexes. Labral surface smooth and asetose. Anterior margin of labrum with a lateral lamella and single broad lamella on each side of median cleft. A row of minute backwardpointing setae present along posterior margin of labrum, another row of 10 slender setae present on each side of anterior margin of lamellae. Number of these anterior slender setae varying among paratypes, ranging from 8 – 12 on each side. (Figs 9 G and 11 D). Lateral palp of gnathochilarium: 1.25 times as long as medial palp. 11 conical sensilla on lateral palp and 22 on medial palp observed on both holotype and paratypes (Fig. 9 E). Trunk: Body with 10 segments, 9 pleural projections, excluding telson and caudal bundle; 13 pairs of legs. Collum with lateral protuberances bearing 4 – 5 trichomes on each side. All other tergites, from 2 to 10, each with a pair of pleural projections located antero-laterally. Tergal trichome socket arrangements typically forming 2 broad oval shapes, slightly enlarged laterally, with posterior row curved slightly upward toward centre with a large gap between these trichome socket rows. Collum with 38 (L) and 38 (R) trichome sockets and 4 (L) and 4 (R) trichome sockets on lateral protuberance of the holotype (Fig. 9 B). Number of trichome sockets varied in paratypes ranging from 36 – 54 and number of lateral protuberances trichome sockets ranging from 4 – 6. Tergite 2 with a similar structural pattern with posterior row slightly longer and 39 (L) and 36 (R) trichome sockets (Fig. 9 C). For tergites 3 – 9, patterns being similar with characteristic large gaps. Tergite 10 with trichome sockets being smaller and denser, a narrow space present between lateral rosette trichome sockets and posterior row (Fig. 9 D). Legs: Leg segments are named following Manton (1956). Legs 1 and 2 are without trochanter, leg 1 also lacks tarsus 1. Chaetotaxy: coxa 1 and 2: 2 setae, coxae 3 – 13: 2 – 3 setae; prefemur, post-femur, tibia with 1 seta, except femur with 1 – 4 setae, tarsus 1 and tarsus 2 with a spine (Figs 12 A and 13 A). Coxa and prefemur, femur with a biarticulated seta with a ridged funicle (Fig. 12 B). 1 – 3 smaller biarticulated setae with the ridged funicles present on posterior position of femur and some also on penis (Figs 12 A and 12 C). At distal edge of post-femur and tibia, a setiform seta present (Fig. 12 D). A spine on tarsus 2 sharply pointed and twice as long as the spine (Fig. 12 F) in the anterosternal position of tarsus 1 (Fig. 12 E). Posterior edge of last sternite with 2 – 4 setae similar to those present on coxa, number of these setae varying; 2 present on holotype and 2 – 4 on paratypes. Telotarsus-Claw: A slender structure with an anterior lateral process, a posterior process less than half the length of claw. Anterior setiform process half of the length of claw; a lamella process present (Figs 12 H and 13 B). Sex organs in the male: A pair of penes present on coxae 2 and 2 pairs of coxal glands located on coxal plates of legs 8 and 9. Telson: Dorsal ornamental trichome sockets arranged almost symmetrically with 8 (L) and 12 (R) sockets of trichomes a on each side of telson in holotype, 7 – 14 sockets trichomes a on each side in paratypes. Sockets of trichomes a being more numerous on telsons of paratypes in 12 legs stage (Stadium VII) with these sockets ranging from 14 – 18 on each side of telson. Sockets of trichomes a forming 2 rows, a top row with small sockets and bottom row with larger sockets. The 2 largest sockets located close to the socket of trichome b. 3 large sockets trichomes c with protruding base: c 1, c 2 and c 3, forming a triangular shape. Circular indentation d apparent each side near exterior side of trichomes c (Figs 12 G, 13 C and 13 D). Caudal bundles: In males, caudal structure comprised of a group of caudal trichome sockets forming a single structure of uniform size (Fig. 13 C). In females, caudal bundle with 2 distinguishing features: a main dorsal structure, carrying caudal trichomes, similar to that of male caudal bundle; and 2 latero-sternal bundles of nest trichomes, smaller sockets compared to caudal trichome sockets. Nest trichomes using for nest building and protecting egg clusters (Huynh and Veenstra, 2014). Caudal bundle structures well defined with borders between caudal and nest trichomes (Fig. 13 D).	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFFE5E430FBDF9CAFD0008CE.taxon	description	The genus Monographis is divided into 2 groups depending on the arrangement of the sensilla on the antennal article VI, forming either a crescent or a triangular shape (Huynh and Veenstra, 2015). M. phuquocensis sp. n. belongs to the group where the sensilla are arranged in a crescent-shape, as does M. kraepelini, M. annandalei, M. baihualingensis, M. demangei and M. mira. These species can be distinguished by characteristics of the labrum and telotarsus. M. phuquocensis sp. n. has a labrum with a smooth, asetose surface which differs from M. kraepelini, M. baihualingensis and M. demangei. Setae on the anterior margin of the lamellae of M. phuquocensis sp. n. are slender compared to those of M. kraepelini, which are acute triangular shaped setae (Nguyen Duy-Jacquemin and Condé, 1967). Despite the similarity in the arrangement of the sensilla on the 6 th antennal article between M. phuquocensis sp. n. and M. demangei, the telotarsus structure is distinctly different in these 2 species. The anterior setiform process from the telotarsus of M. phuquocensis sp. n. is half the length of the claw, which contrasts with M. demangei where the anterior setiform process is longer than the claw.	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
03AB2952FFFE5E430FBDF9CAFD0008CE.taxon	discussion	Remarks. Monographis phuquocensis sp. n. has the characteristics of a group of Monographis species with the sensilla forming a crescent shape on the antennal article VI and a row of slender setae being present on the anterior margin of the labrum. The similarity of characteristics observed in M. phuquocensis sp. n., M. kraepelini, M. baihualingensis and M. demangei makes it challenging to distinguish between these species. M. phuquocensis sp. n. has a distinctive character on the surface of the labrum with the presence of slender setae on the anterior margin of the labrum and the structure of telotarsus. These characters can be used to distinguish this species from all the known species from genus Monographis.	en	Huynh, Cuong (2018): Two new species of penicillate millipedes (Diplopoda, Polyxenidae) from Phu Quoc Island in southern Vietnam. Zootaxa 4402 (2): 283-302, DOI: 10.11646/zootaxa.4402.2.3
