Machadobelba bimorpha, Ermilov & Shtanchaeva & Kalúz, 2025

Machadobelba bimorpha sp. nov. ( Figs. 1–12 View Figures 1–5 View Figures 6–12 )

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Type material

Holotype (male) and three paratypes ( one male and two females): Malaysia, Perak District, 33 km NE to Gerik , 05° 34 ' 42 '' N, 101° 22 ' 44.0 '' E, 350 m a.s.l., forest complex Belum – Temenggor, litter, 2–13.iv.2015 ( E. Jendek and O. Šauša). GoogleMaps

Type deposition

The holotype is deposited in the collection of the Institute of Zoology , Slovak Academy of Sciences, Bratislava, Slovakia ; two paratypes ( one male and one female) are deposited in the collection of the Tyumen State University Museum of Zoology , Tyumen, Russia ; one paratype ( one female) is in the personal collection of the first author. All specimens are preserved in 70% solution of ethanol with a drop of glycerol .

Diagnosis

Body length: 420–435. Rostrum protruding, narrowly rounded. Rostral region with two longitudinal ridges. Costula shorter than half of prodorsum. Sexual dimorphism in morphology of rostral seta (short, dilated mediodistally, with short cilia distally in males versus medium-sized, setiform, sparsely barbed in females); lamellar and interlamellar setae medium-sized, dilated and shortly ciliated mediodistally; bothridial seta bifurcate, with sparsely barbed branches. Medial prodorsal, postbothridial, medial notogastral, and lateral notogastral tubercles well developed. All notogastral setae dilated and shortly ciliated mediodistally; c and p 3 short versus other setae medium-sized. Epimeral, aggenital, anal, and adanal setae short, setiform, sparsely barbed; all genital setae short, setiform, roughened. One pair of epimeral tubercles slightly developed. Discidium elongate triangular. Males with one pair of anoadanal porose areas versus females without anoadanal porose areas.

Description

Measurements – Body length: 435 ( holotype), 420–435 ( paratypes); body width: 225 ( holotype), 195–225 ( paratypes). No differences between males and females in body size.

Integument ( Figs. 4, 5 View Figures 1–5 ) – Body color brown. Body surface densely microfoveolate (visible under high magnification); pedotectum I partially with ridges and tubercles (diameter up to 4); lateral part of body partially with microgranulate cerotegument.

Prodorsum ( Figs. 1–3, 5 View Figures 1–5 ) – Rostrum protruding, narrowly rounded. Rostral region with two thin, longitudinal ridges. Costula well-developed, shorter than half of prodorsum. Sexual dimorphism in morphology of rostral seta: in male, seta comparatively short (19–22), dilated mediodistally, with short cilia distally ( Figs. 1, 2, 4, 5 View Figures 1–5 ); in female, seta medium-sized (28–30), setiform, sparsely barbed ( Fig. 3 View Figures 1–5 ); ro inserted on rostral ridge end. Lamellar and interlamellar setae (34–41) dilated and shortly ciliated mediodistally; exobothridial seta (19–22) setiform, roughened; bothridial seta bifurcate, with short, smooth stalk and long, sparsely barbed branches. Medial prodorsal and postbothridial tubercles rounded distally.

Notogaster ( Figs. 1, 4, 5 View Figures 1–5 ) – Medial notogastral tubercle rounded distally; lateral notogastral tubercle smaller, nearly triangular. Ten pairs of notogastral setae ( c, p 3: 19–26; p 2: 30–34; others: 34– 41) dilated and shortly ciliated mediodistally. Opisthonotal gland opening and all lyrifissures well visible.

Gnathosoma ( Figs. 6–8 View Figures 6–12 ) – Subcapitulum size: 94–102 × 67–71; subcapitular setae a (19–22) and h (22–26) setiform, barbed; m (9–11) setiform, roughened; h thickest, m thinnest; both adoral setae (9–11) setiform, roughened. Palp length: 64–67; setation: 0-2-1-3-9(+ω); postpalpal seta (49) dilated and shortly ciliated mediodistally. Chelicera length: 92–102; seta cha (30) setiform, barbed; chb (19) setiform, slightly barbed.

Epimeral and lateral podosomal regions ( Figs. 4, 5 View Figures 1–5 ) – Epimeral formula: 3-1-3-3; all setae ( 1a, 2a, 3a, 4b: 19–22; others: 28–30) setiform, sparsely barbed. One pair of epimeral tubercles (close to epimeral border IV) slightly developed. Anterior and posterior lateral tubercles rounded distally. Discidium elongate triangular.

Anogenital region ( Figs. 4, 5 View Figures 1–5 ) – Anogenital formula: 6-1-2-3; all genital setae ( g 1: 24–30; others: 17–19) setiform, roughened; aggenital, anal, and adanal setae (19–22) setiform, sparsely barbed. Adanal lyrifissure close and parallel to posterior half of anal plate. Males with one pair of nearly triangular or elongate oval anoadanal porose areas; females without anoadanal porose areas.

Legs ( Figs. 9–12 View Figures 6–12 ) – Claw of each leg strong, slightly barbed dorsal side, without tubercle ventrobasally. Porose area on all segments not observed. Formulas of leg setation and solenidia: I (1- 5-2-4-20) [1-2-2], II (1-5-2-4-16) [1-1-2], III (2-3-1-3-15) [1-1-0], IV (1-2-2-3-12) [0-1-0]; homology of setae and solenidia indicated in Table 1; seta p of tarsus I eupathidial; p of tarsi II–IV thorn-like; s of tarsus I eupathidial, located between paired setae (u) and (a); genua I–IV, femora I–IV, and trochanter III with one or several setae dilated and shortly ciliated mediodistally; solenidion ω 1 of tarsus I, ω 1 and ω 2 of tarsus II, and σ of genu III thickened, rounded distally; φ 1 subflagellate; other solenidia setiform.

Comparison

Machadobelba bimorpha sp. nov. belongs to the complex of Machadobelba View in CoL -species with notogastral setae well dilated mediodistally: M. baloghi Mondal & Kundu, 1999 View in CoL ( India), M. foliata Hammer, 1982 View in CoL (Bali), M. similis Mahunka, 1988 View in CoL (Borneo), and M. spathulifer Mahunka, 1987 View in CoL (Borneo). The new species differs from all species listed above in the presence (versus absence) of the sexual dimorphism in morphology of the rostral seta, as well as two long, longitudinal ridges in anterior part of the prodorsum. Additionally, M. foliata View in CoL , M. similis View in CoL and M. spathulifer View in CoL with setiform bothridial seta (versus bifurcate in M. bimorpha ) and some setiform setae in posterior part of the notogaster (versus all notogastral setae dilated mediodistally); moreover, M. baloghi View in CoL and M. foliata View in CoL with costula reaching rostrum (versus costula shorter than half prodorsum).

Etymology The species name bimorpha alludes to the two morphological forms of the new species.