Monographis cattienensis Huynh 2022, new species
Creators: name: Huynh, Cuong
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Diplopoda
Polyxenida
Polyxenidae
Monographis
Monographis cattienensis

description: Monographis cattienensis new species
Figures 3–7
Material examined: Type specimens. Holotype adult male, to be returned to the Zoological Museum of the Moscow University (ZMUM), Moscow, Russia. Paratypes, 2 males and 2 females (ZMUM), all collected from the study of microarthropods and macrofauna in the Nam Cat Tien National Park during 2004–2005 (Anchkin et. al., 2007), a south-eastern lowland forest, Dong Nai Province, Vietnam; 11.4475N, 107.442778E, elevation 131 m. Specimens were sent to authors by Professor Sergei Golovatch, the collections were preserved in 80% ethanol, the specimens appeared brownish in colour, and most trichomes and antennae were lost.
Diagnosis: Body length 2.6–3.6 mm. Antennal article VI with 14–16 bacilliform sensilla forming crescent shape, setiform sensillum located anterior position, conical sensillum present near centre of crescent. Labrum setose, with long slender anterior setae on anterior margin. Telotarsus with posterior lateral process less than half length of claw, anterior lateral and lamella processes present, anterior setiform process longer than claw.
Description:
Holotype male body 2.6 mm; paratypes: males 2.6–2.8 mm, females 3.4–3.6 mm; caudal bundle in both sexes same length 0.5 mm, nest trichomes in female 0.2 mm.
Head: Each side 8 ommatidia: 4 dorsal, 4 lateral (1 anterior, 2 medial and 1 posterior). Vertex with 2 posterior trichome groups (pv) and a large medial gap. Each group with 2 rows: Anterior row curved slightly, on an oblique angle with large trichome sockets in central position, gradually reducing the size at both ends (holotype 12 each side); posterior row with few small sockets (holotype 2 each side); a narrow space between these rows. (Figures 3A & 3B). Paratypes showed that variation is common in this species, regardless of sex, ranging from 12–16 sockets in anterior rows, 2–3 in posterior rows. Trichobothria: typically thin, sensory hairs with narrow cylindrical funicles; trichobothria equal in socket size forming an isosceles triangle with equal distance ab and bc, trichobothrium a located in interior position, trichobothrium b in lateral position, trichobothrium c in exterior position of the head capsule (Figures. 3A & 3C). Gnathochilarium: Lateral palp 1.25 times medial palp; 11 conical sensilla on the lateral palp and 22 on the medial palp, same in holotype and paratypes (Figure 3D). Clypeo-labrum: Holotype, labrum posterior margin with 12 setae (Se), setae equal in length to labrum width; Paratypes, 10–12 setae in both sexes. Labrum surface setose (l), labrum posterior margin has a row of minute backward-pointing setae (sb). Lateral lamella (Ll) and single broad lamella each side of median cleft (mc); 7 (Left: L) and 12 (Right: R) slender setae (sa) present on anterior margin of labrum. The number of these anterior slender setae varies among paratypes, ranging from 18–20 across both sides. (Figure 3E).
Antennae: Antennal article VI with 15–16 bacilliform sensilla. Holotype with 16 bacilliform sensilla forming a crescent shape with 3 thick (T) and 8 thin bacilliform sensilla (t), 5 short thin bacilliform sensilla (ts); setiform sensillum (S) located in anterior position, conical sensillum (C) present near the centre of the crescent (Figures 4C, 7B & 7C). Antennal article VII with 2 thick bacilliform sensilla (T, Ta and Tp), setiform sensillum (S) located in between these two sensilla (T), conical sensillum (C) located next to Tp (Figure 4B), which is an arrangement typical of the genus.
Body. Collum—the first tergite with a pair of pleural projections called lateral protuberances (Lp) (Figure 5A); tergites 2 (T2) to 10 (T10), each connected with a pair of pleural projections (pp) (Figure 5B); tergite T10—the last tergite, trichome sockets dense and smaller (Figure 5C).
Legs. Leg segmentation following Manton (1956) and with articles typical of Polyxenida: legs 1 and 2 without trochanter, leg 1 without tarsus 1. Chaetotaxy (setae on leg articles): coxa 1 and 2: 2 setae, coxae 3–13: 2–4 setae; pre-femur, post-femur, tibia with 1 seta, except femur with 1–4 setae, tarsus 1 and 2 with a spine. Coxa, pre-femur and femur with biarticulated seta and ridged funicle. 1–3 smaller biarticulated setae in posterior position of femur, some also on penis. Post-femur and tibia distally with setiform seta. The spine on tarsus 2 is sharply pointed and twice the length of a spine in the antero-sternal position of tarsus 1 (Figures 6A–C, 7E, 10A, 12C, 15A, 20A & 23C).
Telotarsus: Claw slender with anterior lateral (a) and posterior lateral (p) processes less than half length of the claw (c); the anterior setiform process (s) is longer than the claw; lamella process (la) is present (Figures 6D & 7F).
Sex organs in the male: A pair of penes on coxae 2 and 2 pairs of coxal glands are located on the 8th–9th coxal plates (Figures 6E & 22B).
Caudal bundles: Similar to congeners (Huynh & Veenstra 2020) and classified as caudal bundle type I arrangement (Condé & Nguyen Duy-Jacquemin, 2008). Caudal trichomes with a series of 2–6 backward hooks (Huynh & Veenstra 2013) (Figures 12B, 23A & 23B).
Telson: Dorsal ornamental trichome sockets symmetrically arranged either side of telson; 17 (L) and 18 (R) sockets of trichomes a on each side of the telson in the holotype (paratypes with 16–18). Trichome a sockets form 2 rows, top row with small sockets, bottom row with larger sockets. Socket of trichome b and 3 large sockets trichomes c with protruding base: c1, c2 and c3, forming triangular shape located in ventroposterior positions in each arrangement. Circular indentation d apparent each side near the exterior side of trichomes c (Figure 6F).
Remarks: Monographis cattienensis sp. n., differs from other species in the genus in several characters. It has a distinctive number of bacilliform sensilla arranged in a crescent shape, setose labrum surface and slender setae present on lamellae along the anterior margin of the labrum, plus an anterior setiform process longer than the claw.
Etymology: Monographis cattienensis is named after the Cat Tien National Park in Dong Nai Province, Vietnam, where this species was collected.
description: Published as part of Huynh, Cuong, 2022, Four new species of Monographis Attems, 1907 (Diplopoda, Polyxenida, Polyxenidae) from Vietnam, pp. 393-420 in Zootaxa 5214 (3) on pages 397-403, DOI: 10.11646/zootaxa.5214.3.4, http://zenodo.org/record/7389267