Deltoxenos maceki Benda & Straka, 2025

Deltoxenos maceki Benda & Straka sp. nov.

Figs 9 A, B View Figure 9 , 10 A – D View Figure 10 , 11 A – D View Figure 11 , 12 A, B View Figure 12

Type material.

Holotype • ♀ ( NMPC), Vietnam: Hoa-binh env. , 9.vi.1986, host: Pareumenes quadrispinosus (Saussure, 1855) , J. Macek lgt., voucher code: PsPa 1 a . Paratypes • ♀ ( NMPC), data the same as holotype, from the same host specimen as holotype, voucher code: PsPa 1 b • 2 ♀ ( OLML), Laos: Khammouan prov., Nakai env. , 550 m, 15.vi.2001, host: Pareumenes quadrispinosus (Saussure, 1855) , E. Jendek lgt., voucher codes: PsQd 2 a, PsQd 2 b .

Additional material.

2 EMP ( NMPC), data the same as holotype, from the same host specimen as holotype.

Diagnosis of female cephalothorax.

This species is diagnosed by a combination of characters. Thorax not elongated as in D. indonesiensis and D. reginus , distinctly widening posteriorly, almost triangular, similar to D. bidentatus (Fig. 10 A View Figure 10 ), but narrow in some specimens (Fig. 10 C View Figure 10 ). Differs from D. rueppelli by rounded and protruding clypeal lobe (cl, Fig. 12 View Figure 12 ), differs from other species in very conspicuous and wide space at border between clypeal and labral areas (sbcl, Fig. 12 A View Figure 12 ) and in shape of maxilla, which partly overlap with mandible (mx, Fig. 12 A View Figure 12 ). From D. hajeki distinguished by anteriorly exposed clypeal sensilla (cls, Fig. 12 A View Figure 12 ) which are mainly concentrated ventrally on the clypeal lobe in D. hajeki ; antennal torulus completely absent in D. maceki while slightly reduced but still present in D. hajeki ; prosternum anteriorly distinctly reticulated without any sensilla × prosternum differentiated, anteriorly with field of sensilla in D. hajeki .

Description of female cephalothorax.

Shape and colouration. Size of holotype cephalothorax: length 1.5 mm, width 1.16 mm. Size of cephalothorax: length 1.44–1.5 mm, width 1.18–1.46 mm (Fig. 10 View Figure 10 ). Cephalothorax only slightly varying in length but distinctly variable in width (compare Fig. 10 A View Figure 10 with Fig. 10 C View Figure 10 ). Constriction at pro-mesothoracic segmental border indistinctly visible, meso-metathoracic segmental border conspicuously constricted laterally (sbpm, sbmm, Fig. 10 A View Figure 10 ). Abdominal segment I not protruding laterally, corner below spiracles rounded. Anterior head margin rounded, slightly protruding from remaining head capsule. Thorax not elongated, distinctly widening posteriorly or narrow in few specimens. Cephalothorax with conspicuously contrasting pale and dark colour pattern but predominantly pale.

Head capsule. Ca 1 / 3 as long as entire cephalothorax including lateral cephalic extension. Colouration forming specific pattern with predominantly light parts and dark brown mandible and labium. Surface of lateral extensions at site of reduced compound eyes smooth, laterally with slightly wrinkled cuticle and indistinct longitudinal grooves, dark-coloured. Clypeal area well delimited from labral area, arcuate, clypeal lobe slightly protruded from head capsule. Border between clypeal and labral area distinct and wide (sbcl, Fig. 12 A View Figure 12 ). Clypeal surface smooth to slightly wrinkled with distinctly exposed sensilla mainly concentrated anteriorly on clypeal lobe (cls, Fig. 12 A View Figure 12 ). Dorsal side of clypeal area wrinkled (cl, Fig. 12 B View Figure 12 ). Border between clypeal and frontal region indistinct but still present. Frontal region distinctly reticulated and wrinkled (fr, Fig. 12 B View Figure 12 ). Segmental border between head and prothorax indicated by very indistinct mesal furrow on dorsal side (sbhp, Fig. 11 B View Figure 11 ) and by distinct dark transverse stripe visible on colour photograph (sbhp, Fig. 10 D View Figure 10 ). Head and prothorax distinctly separated by birth opening ventromedially (bo, Fig. 11 A View Figure 11 ) and laterally by suture (sbhp, Fig. 11 A View Figure 11 ).

Supra - antennal sensillary field. Completely reticulated and wrinkled, with dispersed sensilla inserted in cavities (sssf, Figs 11 C View Figure 11 , 12 B View Figure 12 ). Very slightly delimited on medial side, almost unrecognisable (fssf, Fig. 12 B View Figure 12 ), surface of supra-antennal sensillary field and frontal region with different sculpture.

Antenna. Preserved as poorly defined area, with numerous vestigial sensilla and inconspicuous cavities (a, Fig. 11 C View Figure 11 ). Antennal torulus completely absent, no border present as between antenna and periantennal area. Periantennal area reticulated, wrinkled (paa, Fig. 11 C View Figure 11 ).

Labrum. Ventral field wider than long, elliptic. Dorsal field very slightly arcuate, flat, not raised, laterally not narrower than medially, 5 × wider than long in midline (vlf, dlf, Fig. 12 A View Figure 12 ). Dorsal field with ~ 25 sensilla inserted in cavities, sensilla dispersed laterally (dlf, Fig. 12 A View Figure 12 ).

Mandible. Mandibles anteromedially directed at angle of 40–45 ° (45 ° in holotype), enclosed in mandibular capsule. Mandibular bulge distinctly raised, elongated, directed anteriorly, with several sensilla (mdb, Fig. 12 A View Figure 12 ). Cuticle of mandible almost completely smooth, without lateral longitudinal furrows. Mandibular tooth slightly curved, pointed anteriorly, not conspicuously armed with spines (mdt, Fig. 12 A View Figure 12 ).

Maxilla. Well-developed and prominent, separated from labial area (mx, Fig. 12 A View Figure 12 ). Mostly dark, medially pale; cuticle smooth medially, reticulated laterally. Apical maxillary region not projecting beyond mandibular apex. Basal part connected with labium, anterior part slightly overlapping with mandible (mx, Fig. 12 A View Figure 12 ). Vestige of palp present, conspicuous, located medially on ventral side of maxilla (mxp, Fig. 12 A View Figure 12 ). Maxillary base distinctly produced anterolaterally as submaxillary groove. Space between prothoracic extension and head not widened (sbhp, mxb, Fig. 11 A View Figure 11 ).

Labium. Labial area between maxillae distinct, delimited anteriorly by mouth opening and posteriorly by birth opening (lb, Fig. 12 A View Figure 12 ). Flat, approximately as long as wide. Cuticular surface very slightly reticulated.

Mouth opening. Very variable, laterally arcuate, medially sinuate to straight, area around mouth opening dark (os, Fig. 12 A View Figure 12 ).

Thorax. Pro-mesothoracic and meso-metathoracic borders visible ventrally as slightly imprinted mesal furrows (sbpm, sbmm, Figs 10 A View Figure 10 , 11 A View Figure 11 ). On dorsal side separated by conspicuous dark mesal furrows, distinctly contrasting with pale thoracic segments (sbpm, sbmm, Figs 10 B View Figure 10 , 11 B View Figure 11 ). Border between metathorax and abdomen indicated by ventral ridge on ventral side or indicated by change in colour and cuticular sculpture. Cuticle of thoracic segments on ventral side mostly pale except prothorax, with conspicuous pigmented papillae. Prosternum differentiated, anteriorly distinctly reticulated but without any sensilla; prosternum with typical colour pattern – dark anteromedially and laterally. Mesosternum and metasternum with two areas of dark papillae (mstp, mtstp, Fig. 10 A View Figure 10 ). Cuticular surface of prosternal and mesosternal dark spots smooth, without any papillae or reticulation. All thoracic segments mostly pale dorsally and laterally. Meso- and metathorax transverse, rarely slightly elongated.

Abdominal segment I and spiracles. Setae and cuticular spines present on lateral region of abdominal segment I posterior to spiracle (cus, Fig. 11 D View Figure 11 ). Spiracles on posterior ~ 1 / 3 of cephalothorax very slightly elevated, with anterolateral orientation. Cephalothoracic part of abdominal segment I below spiracles orange to dark brown on both sides (asI, Fig. 10 B View Figure 10 ).

Host.

Pareumenes quadrispinosus (Saussure, 1855) .

Phylogenetic relationships.

Unknown.

Distribution.

Vietnam, Laos.

Etymology.

Named after Jan Macek (National Museum of the Czech Republic, Prague), a dear colleague and friend, as well as a world expert on Hymenoptera, who collected part of the type material.