Deltoxenos, Benda & Pohl & Nakase & Beutel & Straka, 2022
|
publication ID |
https://dx.doi.org/10.3897/zookeys.1093.72339 |
|
publication LSID |
lsid:zoobank.org:pub:23B70708-49A9-4681-AC20-494D06F98CCE |
|
persistent identifier |
https://treatment.plazi.org/id/78A7DB5E-AA8B-4DCE-9F60-2001D2B218CB |
|
taxon LSID |
lsid:zoobank.org:act:78A7DB5E-AA8B-4DCE-9F60-2001D2B218CB |
|
treatment provided by |
|
|
scientific name |
Deltoxenos |
| status |
gen. nov. |
Deltoxenos gen. nov.
Type species.
Pseudoxenos bidentatus Pasteels, 1950, here designated.
Diagnosis of female cephalothorax.
Maxilla not prominent, only slightly raised or nearly fused to labial area. Meso-metathoracic segmental border slightly or distinctly constricted laterally (Fig. 47C, D View Figure 47 ), especially in species with elongated cephalothorax. Pro-mesothoracic segmental border rarely constricted. Dorsal labral field slightly or distinctly arcuate, raised or flat, in the latter case narrower laterally than medially (Fig. 3A View Figure 3 ). Lateral parts of abdomen posterior to spiracles not pale (Figs 1B View Figure 1 , 47D View Figure 47 ). Mandible not protruding from capsule. In contrast to Paragioxenos , head and prothorax ventrally delimited by birth opening medially and by suture laterally.
Description of female cephalothorax.
Shape and coloration. Very variable, ca. as long as wide, slightly wider than long, or distinctly longer than wide. Meso-metathoracic segmental border slightly or distinctly constricted laterally (Fig. 47C, D View Figure 47 ), especially in species with elongated cephalothorax. Pro-mesothoracic segmental border rarely constricted. Extremely variable in size, length 0.9-2.83 mm, maximum width 0.74-2.43 mm. Anterior head margin evenly rounded or protruding. Thorax slightly or distinctly widening posteriorly, sometimes nearly parallel-sided. Cephalothorax with conspicuous color pattern. Coloration comprising multiple brown and orange shades forming distinct pattern.
Head capsule. Ca. ¼ ~ ½ as long as entire cephalothorax including lateral cephalic extension. Coloration of head forming specific color pattern with pale and dark combined. Clypeal area well delimited from labral area, arcuate, or protruding and forming clypeal lobe. Surface smooth or slightly wrinkled. Sensilla (24 to 45 or more) regularly distributed on clypeal area or mainly concentrated on clypeal lobe. Border between clypeal region and frontal area not clearly distinguishable but border still recognizable. Cuticle of frontal region very variable, from distinctly wrinkled, slightly wrinkled to nearly smooth, or covered with distinct papillae. Border between head and prothorax well visible or faintly recognizable on dorsal side, often indicated by colored transverse stripe (Fig. 1B View Figure 1 ).
Supra-antennal sensillary field. Smooth, wrinkled or reticulated, with dispersed sensilla. Not delimited or indistinctly delimited by furrow on medial side, but border of field still distinctly visible (Figs 4A View Figure 4 , 49B View Figure 49 ).
Antenna. Preserved as poorly defined area, with several small, rounded plates, antennal sensilla, or cavity, often combined (Figs 4B View Figure 4 , 48C View Figure 48 ). Periantennal area smooth or wrinkled.
Labrum. Ventral field wider than long, elliptic to nearly circular. Dorsal field slightly or distinctly arcuate, raised, or flat and laterally narrower than medially (Fig. 3A View Figure 3 ). Ca. 4-6 × wider than long in midline. Dorsal field with ~ 10-25 setae or sensilla inserted in cavities.
Mandible. Mandibles anteromedially directed at an angle of 25-65° and nested in mandibular capsule. Mandibular bulge distinctly raised, with several sensilla. Cuticle of mandible completely smooth to partially sculptured (Fig. 49E View Figure 49 ). Mandibular tooth narrow or slightly widened, pointed apically or ventrally, armed with spines.
Maxilla. Very variable in shape, distinctly reduced and almost fused with labial area, or slightly raised but not distinctly prominent (Figs 3B View Figure 3 , 49E View Figure 49 ). Cuticle smooth or wrinkled. Apical maxillary region not or slightly projecting beyond mandibular apex. Basal portion firmly connected with labium and not overlapping with mandible, or in some cases elevated and overlapping with mandible very slightly. Vestige of palp inconspicuous, forming cavity or poorly defined area with indistinct plate. Usually located medially on ventral side of maxilla (Fig. 3B View Figure 3 ). Maxillary base more or less distinctly produced anterolaterally as submaxillary groove.
Labium. Labial area usually distinct between maxillae, delimited anteriorly by mouth opening and posteriorly by birth opening. Flat, longer than wide or wider than long. Cuticular surface smooth or reticulated.
Mouth opening. Widely arcuate to nearly straight or bisinuate, sclerotized along margin.
Thorax and abdominal segment I. Pro-mesothoracic and meso-metathoracic borders more or less distinct, usually separated by mesal furrows, combined with pigmented stripes or spots on dorsal and ventral side (Figs 1A, B View Figure 1 , 47C, D View Figure 47 ). Border between metathorax and abdomen usually formed by ridge or indicated by change of cuticular sculpture (Fig. 1A View Figure 1 ). Cuticle of thoracic segments on ventral side reticulate with scattered inconspicuous or more distinct pigmented papillae. Dorsal side of thorax smooth or slightly reticulated. Prosternal extension undifferentiated, evenly arched. Meso- and metathorax usually transverse or elongated in some cases. Lateral parts of abdomen posterior to spiracles dark (Figs 1B View Figure 1 , 47D View Figure 47 ). Setae and cuticular spines present on lateral region of abdominal segment I (Fig. 48E, F View Figure 48 ).
Spiracles. Located on posterior third of cephalothorax, slightly elevated with anterodorsal and anterolateral orientation.
Diagnosis of male cephalotheca.
Differing from other genera by the following combination of characters. Diameter of genae between maxillary base and compound eye at least 2 × as large as diameter of vestigial antenna. Distinct paired furrow of supra-antennal sensillary field absent. Cephalotheca always elliptic (Figs 5A View Figure 5 , 50A View Figure 50 ). Frontal fissure hardly distinct of nearly absent (Figs 6A View Figure 6 , 50D View Figure 50 ). Maxilla not distinctly elongated, at most 1.5 × longer than basally wide (Fig. 50E View Figure 50 ). Occipital bulge well developed (Figs 6A View Figure 6 , 50D View Figure 50 ). Coloration forming pattern of pale and dark shades (Figs 5A View Figure 5 , 50A View Figure 50 ).
Description of male cephalotheca.
Shape and coloration. In frontal view rounded laterally, elliptic, in lateral view pointed anteriorly. Coloration forming pattern of pale and dark shades.
Cephalothecal capsule. Compound eyes with darker individual ommatidia well visible on pale ocular background. Clypeal lobe straight or slightly arcuate in frontal view, prominent in lateral view, in some cases bulging (Figs 6B View Figure 6 , 50D View Figure 50 ). Sensilla mainly concentrated on clypeal lobe. Frontal impression more or less distinct (Figs 5A View Figure 5 , 6A View Figure 6 ). Occipital bulge distinct (Figs 5A View Figure 5 , 50D View Figure 50 ). Diameter of genae between maxillary base and compound eye smaller,> 2 × larger than diameter of vestigial antenna.
Supra-antennal sensillary field. Kidney-shaped and bulging, medially delimited by more or less distinct frontal impression, lacking furrows.
Antenna. Of standard shape, with recognizable complete torulus. Periantennal area not clearly delimited from supra-antennal sensillary field. Small plates, cavities or sensilla present.
Labrum. Labral area distinct, with setae on dorsal field.
Mandible. Anteromedially directed. Mandibular bulge with sensilla, separated from pointed tooth.
Maxilla. Distinct, prominent, completely dark. Vestige of palp distinct.
Labium and hypopharynx. Labium distinct between and below maxillae, dark. Praementum and postmentum separated by furrow. Hypopharyngeal protuberance present or not.
Mouth opening. Well visible, not covered by ventral labral field, distinctly arcuate.
Phylogenetic relationships.
Deeply nested within Xenidae , with Xenos as sister group ( Benda et al. 2019; Straka and Benda unpubl. results).
Diversity and distribution.
A lineage of Afrotropical origin with later expansion to the Palearctic and Indomalayan regions ( Benda et al. 2019). Present distribution of 7 species comprising the Old World and Australasian region.
Hosts.
Various genera of Eumenini and Odynerini ( Vespidae : Eumeninae ).
Etymology.
Name derived from the generic name Delta Saussure, one of the most common host genera. Gender masculine.
Comments.
All described species of Deltoxenos gen. nov. were previously placed in Pseudoxenos based on parasitism in solitary wasps ( Kinzelbach 1971b). Despite this concept, this group is morphologically well defined. Although this group was not recognized in Kinzelbach’s concept, we classify it as a separate genus based on molecular phylogenies ( Benda et al. 2019, 2021) and morphological characters newly reported here.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.