Prionoglaris kapralovi, Lienhard, 2021

Lienhard, Charles, 2021, A new species of Prionoglaris Enderlein (Psocodea: ‘ Psocoptera’: Prionoglarididae) from an Armenian cave, with an account of the distribution of the genus, Revue suisse de Zoologie 128 (2), pp. 227-235 : 228-233

Prionoglaris kapralovi sp. nov.

Figs 1-2

Holotype: MHNG; male (some parts slide-mounted); Armenia, 8.3 km SW of Yeghegnadzor, Mozrov Cave ; WGS84 39.71258, 45.25953; 1540 m a.s.l., under stones near cave entrance; 14.AUG.2018; leg. S. A. Kapralov.

Paratype: MHNG; female (some parts slide-mounted); same data as for holotype.

Diagnosis: This new species can be distinguished from all known species of the genus Prionoglaris by the absence of an internal membranous vesicle on the anterior claw and by the absence of a basal tooth on the posterior claw of each pretarsus ( Fig. 2 C-D). See also key below.

Etymology: The species is dedicated to Sergei A. Kapralov who collected the type material.

Description

General characters: Head and thorax (including antenna, maxillary palp and legs) yellowish to light or medium brown. Vertex, frons and genae with some small brown patches. Compound eye uniformly dark grey to black (after 2 years in alcohol). Wings hyaline, veins medium brown, pterostigma colourless but slightly opaque ( Fig. 1B ). Abdomen whitish, dorsally and laterally with numerous patches of dark hypodermal pigment forming irregular transversal bands ( Fig. 1 A-B). Terminalia light to medium brown, ventro-median process of phallosome dark brown ( Fig. 1C ).

Mouthparts typical for the genus; lacinial rudiment with an acuminate tip ( Fig. 2E ). Antennae long and slender ( Fig. 1A ), both damaged in male and female examined (highest number of flagellomeres observed is 7, in right antenna of holotype, 7th flagellomere broken near base). Anterior claw of each pretarsus ( Fig. 2C ) with a long basal seta, lacking internal membranous vesicle and preapical denticle. Posterior claw of each pretarsus simple ( Fig. 2D ), lacking basal tooth and preapical denticle. Forewing broadly rounded, clearly longer than twice its width (FW/FWw about 2.4); venation typical for the genus ( Fig. 2A ), but AP somewhat shorter in male than in female (in male its marginal length about same as its height, see Fig. 1A ; in female marginal length slightly exceeding height, see Fig. 2 A-B). Hindwing as in P. stygia . Vein aberrations observed in forewings and hindwings: right forewing of female with a crossvein between R1 and R2 +3, and M1 bifurcate near wing margin ( Fig. 2B ); right forewing of male with a short spurvein on R1 , just basally to point where Sc reaches R1 ( Fig. 1A ); left hindwing of male with a transversal vein between R1 and Rs ( Fig. 1A ), and both hindwings of female with slightly aberrant M2.

Male genitalia: Sac-like proximal body of phallosome relatively short ( Fig. 2 H-I), about half of total length of phallosome; ventro-median process strongly curved in lateral view ( Fig. 2H ); dorso-lateral appendages of about same width between base and apex, only weakly narrowing towards apex ( Fig. 2I ); medio-internal appendage with one fine hair on each side ( Fig. 2 H-I).

Female genitalia: Subgenital plate and gonapophyses typical for the genus, only external valvula well developed, bearing 6 apically hooked setae near broadly rounded apex. Spermapore sclerite a thick and heavily sclerotized plate, proximally broadly rounded, distally narrowly rounded ( Fig. 2F ); spermathecal duct curved inside the sclerite ( Fig. 2G ) and widened towards spermathecal vesicle shortly after the spermapore sclerite (length of the narrow portion of the duct, before widening, about 1.5 times length of spermapore sclerite).

Measurements: Male: BL = 3.3 mm; FW = 3.7 mm; FWw = 1.5 mm; HW = 2.5 mm; IO/D = 1.8. – Female: BL = 4.1 mm; FW = 4.1 mm; FWw = 1.7 mm; HW = 2.7 mm; IO/D = 1.9.

Distribution: Only known from type locality in Armenia.

Type locality: Armenia, Mozrov Cave near Yeghegnadzor, 1540 m a.s.l. This cave is situated on the rolling steppe-like plateau on the left bank of the Arpi river.

Remarks: Judging from most morphological characters, especially the male genitalia, this species clearly belongs to the genus Prionoglaris . However, the asymmetry of the claws of each pretarsus is less pronounced in the new species than in the other species of this genus, especially due to the absence of the membranous vesicle on the anterior claw. This membranous extension is always well developed in the other species of Prionoglaris . The presence of a membranous extension on the anterior claw has been considered as an autapomorphy of the subfamily Prionoglaridinae ( Lienhard, 2004) . No intra-generic variability concerning this character has previously been observed in this subfamily. The membranous extension is particularly well developed in the Oriental genus Siamoglaris Lienhard, 2004 , and in the fossil genus Palaeosiamoglaris Azar, Huang & Nel in Azar et al., 2017 from Burmese amber, but weakly developed in the fourth genus of this subfamily, the troglobitic Speleopsocus Lienhard in Lienhard et al., 2010a which is only known from a single Venezuelan cave. Therefore the absence of this structure in the new species has to be interpreted as an apomorphic reduction. See the discussion below.

Remarks on a Moroccan sample of

Prionoglaris stygia

The only morphological character that distinguishes the closely related species P. stygia and P. dactyloides is the shape of the dorso-lateral appendages of the phallosome. Specimens from a Moroccan sample assigned to P. stygia , collected in the Friouato Cave (see Distribution, below), slightly differ from European P. stygia by the shape of these appendages, and by the presence of a preapical denticle on the posterior claw of each pretarsus ( Fig. 3C ). The dorso-lateral appendages of the phallosome are apically slightly narrowing in the Morrocan males ( Fig. 3 E-F and Lienhard, 1996: figs 4-6, 1998: fig. 41b), while they are broadly rounded in P. stygia males from the type locality of this species ( Fig. 3I ) and in most other European males. The variability of the phallosome in several European populations of P. stygia and in the two known Greek populations of P. dactyloides from the Peloponnese (male holotype) and from Eastern Crete (male paratype) was illustrated by Lienhard (1988: figs 17-36). These figures also show the high variability of the number of fine lateral hairs of the medio-internal appendage of the phallosome (1-13 hairs on each side, but often not the same number on both sides of the appendage). Here figures of the dorso-lateral and mediointernal appendages of two additional European males are presented, one from Switzerland ( Fig. 3G ), the other from Spain ( Fig. 3H ). Both males are somewhat intermediate between P. stygia males from the type locality ( Fig. 3I ) and the Moroccan males ( Fig. 3 E-F). However, the preapical denticle on the posterior claw, always present in the Moroccan specimens (though sometimes smaller than in Fig. 3C ), is completely absent in these two males, as it is generally the case in the European P. stygia and in P. dactyloides (only in one mesothoracic leg of a paratype of the latter could a minute preapical denticle be observed).

When looking for other potentially diagnostic characters which could allow the Moroccan specimens to be distinguished from the European P. stygia , I discovered some differences in the ratio between forewing length and width (FW/FWw) and in the micromorphology of the spermapore sclerite. In both sexes the Moroccan specimens have particularly broad and slightly shortened wings ( Fig. 3D ), with FW/FWw varying from 2.0 to 2.1 (N = 2). In the European P. stygia forewings are clearly longer than twice their width, FW/FWw varying from 2.2 to 2.5 (N = 6; the mean is 2.4). In P. dactyloides this ratio varies from 2.1 to 2.3 (N = 2).

In the only Moroccan female available for this study the spermapore sclerite is proximally broadly rounded and distally slightly elongated and beak-shaped ( Fig. 3K ). In the European P. stygia this sclerite is similar in shape to that of P. kapralovi sp. nov., i.e. narrowly rounded distally but not elongated and beak-shaped (see figures in Lienhard, 1988, 1998). However, in a female of P. stygia from the type locality (French Pyrenees) a distally weakly elongated spermapore sclerite was observed ( Fig. 3M ), about intermediate in shape between the other P. stygia and the Moroccan female.

In view of the considerable variability of the above mentioned characters, and of the low numbers of specimens examined for this study, the slight differences observed between the Moroccan population and the European P. stygia are not sufficient to warrant a formal separation of the Moroccan form as a new species. The only character which can be considered as diagnostic for the Moroccan form is the presence of a preapical denticle on the posterior claw of each pretarsus.

Prionoglaris kapralovi sp. nov.

Previous records: Armenia, see description above.

Figures

Fig. 1. Prionoglaris kapralovi sp. nov. (A) Habitus of male, dorsal view of holotype, in alcohol (body length 3.3 mm). (B) Habitus of female, lateral view of paratype, in alcohol (body length 4.1 mm). (C) Male terminalia, ventral view of holotype, in alcohol. Photographs by S. A. Kapralov.

Fig. 2. Prionoglaris kapralovi sp. nov., female (A-G), male (H-I). (A) Left forewing. (B) Right forewing. (C) Anterior claw of hind pretarsus. (D) Posterior claw of hind pretarsus. (E) Lacinial rudiment (length 0.2 mm). (F) Spermapore sclerite and distal part of spermathecal duct, ventral view. (G) Idem, optical longitudinal section, lateral view. (H) Phallosome, lateral view. (I) Idem, ventral view.

Fig. 3. Prionoglaris spp.: P. stygia males from Friouato Cave, Morocco (A-F), P. stygia male from Pierre à Perret Cave, Switzerland (G), P.stygia male fromW of Atzeneta del Maestrat, Spain (H), P.stygia male from the type locality, Compagnaga Cave, French Pyrenees (I), P. dactyloides, male holotype (J), P. stygia female from Friouato Cave, Morocco (K-L), P. stygia female from the type locality, Compagnaga Cave, French Pyrenees (M). – (A) Phallosome, ventral view. (B) Anterior claw of hind pretarsus. (C) Posterior claw of hind pretarsus. (D) Left forewing. (E-J) Dorso-lateral appendages and medio-internal appendage of phallosome, not in situ (E same male as in A). (K-M) Spermapore sclerite and distal part of spermathecal duct (K and M ventral view; L optical longitudinal section, lateral view).