Paramanicapsocus xingyuei Liang, 2023

Chen, Shengfu, Wang, Menglin & Liang, Feiyang, 2023, A new species of the bark louse genus Paramanicapsocus (Insecta, Psocodea, Manicapsocidae) from mid-Cretaceous Burmese amber, Zootaxa 5315 (3), pp. 264-270 : 265-268

Paramanicapsocus xingyuei Liang sp. n.

( Figs 1–25 )

Diagnosis. Male and female macropterous. Head bearing setae. Antennae elongate, with fifteen antennomeres. Wings hyaline, with well-developed venation. Forewing pterostigma present; R two-branched; M three-branched or two-branched; areola postica (ap) cell present, similar to pterostigma in shape. Hindwing M two-branched; A two-branched. Terminalia: clunium, epiproct, paraproct and hypandrium simple. Male phallosome not visible. Female gonapophyses robust, external valve broad and rounded with hook-like tip, dorsal valve curved, ventral valve with a sharp tip. This new species can be distinguished from P. longiantennatus based on the hindwing vein M two-branched and the female gonapophyses with robust external valves.

Description. Male ( Figs 1–18 ). Head ( Figs 5–6 ) bearing numerous setae. Compound eyes and ocelli bulged. Coronal suture visible, frontal suture not visible. Antennae elongate, setose; flagellum with 13 flagellomeres, and secondary annulations. Postclypeus bulged, epistomal suture distinct. Lacinia ( Fig. 7 ) with bifurcate tip. Maxillary palps ( Fig. 7 ) four-segmented, bearing setae, mx4 equal to mx2, longer than mx1 and mx3, mx4 with a group of short sensory setae on tip. Labial palps ( Fig. 7 ) one-segmented, broad.

Thorax. Prothorax narrow and short, meso- and metathorax robust.

Wings ( Figs 8–11 ). Forewing elongate, partly bearing setae, all veins and whole margin with dense setae. Pterostigma present, with curved posterior margin. Sc not visible; Sc’ very short, with an obvious nodus ( Fig. 9 ); Rs two-branched; M three-branched; crossvein m-cu 1 absent; CuA 1 elongate and curved, CuA 2 very short, shape of areola postica similar to pterostigma, CuP weaker than CuA, meeting A 1 at forewing margin; in-flight wing-coupling structure ( Fig. 10 ) brush-shaped; A 2 present. Hindwing ( Fig. 11 ) margin with setae, veins and membrane without setae; Sc not visible, Rs two-branched, M two-branched, CuA simple, CuP weaker than CuA; vein A bifurcate, A 1 long, A 2 very short. Legs with dense setae; every trochanter ( Fig. 12 ) with a group of setae; tarsi ( Fig. 13 ) three-segmented, 1 st hind tarsus with one row of ctenidiobothria; claw ( Fig. 14 ) with a seta-shape pulvillus.

Terminalia ( Figs 15–18 ) sclerotized. Clunium simple. Epiproct and paraproct bearing setae; hypandrium simple; phallosome not visible.

Measurements (in micron). Body length 2.28 (measure from frons to terminalia); f1=0.4, f2=0.55, f3=0.48; forewing length 2.50, width 0.63; hindwing length 2.00, width 0.58; ft1= 0.20 ft 2=0.05, ft3=0.07; mt1=0.20, mt2=0.07, mt3=0.08; ht1=0.50, ht2=0.09, ht3=0.07.

Female ( Figs 19–25 ). Body ( Figs 19–20 ) and wings ( Figs 21–22 ) similar to male. Forewing ( Fig. 21 ) with short Sc and M two-branched.

Terminalia ( Figs 23–25 ). Clunium simple. Epiproct subtrapezoid. Subgenital plate simple, and strongly sclerotized; a pair of sclerotized regions on the sternum before subgenital plate. Gonapophyses visible, external valve broad and rounded with hook-like tip, dorsal valve curved, ventral valve with a sharp tip.

Measurements (in microns). Body length 2.25 (measure from frons to terminalia); f1=0.40, f2=0.36, f3=0.36; forewing length 2.58, width 0.74; hindwing length, width 0.53; ft1=0.25, ft2=0.05, ft3=0.08; mt1=0.30, mt2=0.05, mt3=0.08; ht1=0.60, ht2=0.08, ht3=0.11.

Examined material. Holotype: male, CAU-BA-LFY-23001; paratypes: male, CAU-BA-LFY-23002; female, CAU-BA-LFY-23003; female, CAU-BA-LFY-23003.

Locality and horizon. Hukawng Valley, Kachin State, Northern Myanmar. Mid-Cretaceous, lowermost Cenomanian.

Etymology. The new species is dedicated to Prof. Xingyue Liu for his support and contributions to the study of Psocodea from China.

Remarks. This new species belongs to the genus Paramanicapsocus based on the body bearing setae, the long antenna, mx4 with a group of short sensilla on the tip, part of forewing bearing dense setae, the ap cell similar to the pterostigma in shape, the in-flight wing-coupling structure brush-shaped, the 1 st tarsomere longer than 2 nd plus 3 rd tarsomeres, 1 st hind tarsomere with one row of ctenidiobothria, and the seta-shaped pulvillus. This new species shares many diagnostic characteristics with the type species P. longiantennatus , and can be distinguished from the latter by the hindwing M two-branched.

In this new species, females display similar body morphologies as males, except for the forewing M and the terminalia. The females have M two-branched on forewing, while the males have M three-branched. In some previous studies on the Psocodea from Cretaceous amber, the intraspecific variations of venation were described, i.e., Concavapsocus parallelus Wang et al., 2019 and Psyllipsocus yangi Liang & Liu, 2021 . The above variations in the two species are regarded as abnormal because the venations are asymmetric on wings. Hakim et al. (2020) described an abnormality in the venation of P. longiantennatus : one of the forewings has M two-branched instead of three in the paratype NIGP169669. In the present study, we consider the variable forewing M to be normal in Paramanicapsocus xingyuei sp. n. because of the symmetric venations on wings in every individual. It seems that this characteristic is sex-linked in this new species. However, we cannot confirm it is common in the genus Paramanipsocus. More materials will be helpful to understand this phenomenon in the future.

The discovery of this new species increases our knowledge of the diversity of the genus Paramanicapsocus from Cretaceous amber. This new species is the second species of Paramanicapsocus , and the fifth species of the family Manicapsocidae from Cretaceous Burmese amber.Although Paramanicapsocus is tentatively placed into the family Manicapscoidae , the placement of Manicapsocidae and the phylogenetic relationship within the infraorder Amphientometae remain controversial up to now. Future studies with more materials, including extinct and extant electrentomoids, will be helpful to better understand and resolve these problems.

Figures

FIGURES 1–4. Paramanicapsocus xingyuei sp. n., male. 1. Habitus, holotype, CAU-BA-LFY-23001, dorsal view; 2. Habitus, holotype, CAU-BA-LFY-23001, ventral view; 3. Habitus, paratype, CAU-BA-LFY-23002, dorsal view; 4. Habitus, paratype, CAU-BA-LFY-23002, ventral view. Scale bars=0.5 mm.

FIGURES 5–11. Paramanicapsocus xingyuei sp. n., male.5. Head, holotype, CAU-BA-LFY-23001, dorsal view, Scale bar=0.5 mm; 6. Head, holotype, CAU-BA-LFY-23001, ventral view, Scale bar=0.5 mm; 7. Head, paratype, CAU-BA-LFY-23002, lateral view, Scale bar=0.5 mm; 8. Forewing, Scale bar=0.5 mm; 9. Nodus, Scale bar=0.05 mm; 10. In-flight wing-coupling structure, Scale bar=0.05 mm; 11. Hindwing, Scale bar=0.5 mm.

FIGURES 12–18. Paramanicapsocus xingyuei sp. n., holotype, CAU-BA-LFY-23001, male. 12. Trochanters, arrow to trichobothrial fields, Scale bar=0.5 mm; 13. Tarsi, Scale bar=0.5 mm; 14. Claw, arrow to pulvillus, Scale bar=0.2 mm; 15. Photograph of terminalia, dorsal view, Scale bar=0.5 mm; 16. Drawing of terminalia, dorsal view, Scale bar=0.25 mm; 17. Photograph of terminalia, ventral view, Scale bar=0.5 mm; 18. Drawing of terminalia, ventral view, Scale bar=0.25 mm. Cl: clunium; pp: paraproct; ep: epiproct; hy: hypandrium.

FIGURES 19–25. Paramanicapsocus xingyuei sp. n., female. 19. Habitus, paratype, CAU-BA-LFY-23003, dorsal view, Scale bar=0.5 mm; 20. Habitus, paratype, CAU-BA-LFY-23004, dorsal view, Scale bar=0.5 mm; 21. Forewing, Scale bar=0.5 mm; 22. Hindwing, Scale bar=0.5 mm; 23. Photograph of terminalia, CAU-BA-LFY-23003, ventral view, Scale bar=0.5 mm; 24. Photograph of terminalia, paratype, CAU-BA-LFY-23003, dorsal view, Scale bar=0.5 mm; 25. Drawing of terminalia, paratype, CAU-BA-LFY-23003, dorsal view, Scale bar=0.25 mm; Cl: clunium; pp: paraproct; ep: epiproct; ev: external valve; dv: dorsal valve; vv: ventral valve.