Psyllipsocus similis Lienhard, 2013

Lienhard, Charles & Ferreira, Rodrigo L., 2013, Three new species of Psyllipsocus (Psocodea: ‘ Psocoptera’: Psyllipsocidae) from Brazilian caves with description of a novel structure interpreted as a male accessory genital organ, Revue suisse de Zoologie 120 (3), pp. 421-443 : 433-438

Psyllipsocus similis Lienhard n. spec. Figs 7F, 8-9

HOLOTYPE: ISLA; 3 (slide-mounted); BRAZIL ( MG), Itambé do Mato Dentro , cave

Baixada dos Crioulos 2, 29.vii.2004, leg. R. L. Ferreira.

PARATYPES: ISLA and MHNG, slide-mounted and/or in alcohol ; BRAZIL, leg. R. L. Ferreira, from the following municipalities. 1♀, Itabirito ( MG), cave Gruta MP8 , 8.ix.2005. – 33, 2♀ (one of them allotype), 2 specimens lacking abdomen, Itambé do Mato Dentro ( MG), cave Baixada dos Crioulos 2, 29.vii.2004. – 13, Moeda ( MG), cave SMS 19, 3.xii.2005 .

DESCRIPTION: See diagnosis of the species group, with the following complements. General colouration yellowish to medium brown. Head often with some patches of brown hypodermal pigment, especially on frons, compound eyes dark brown to black. Tibiae uniformly brown, lacking transversal bands. Abdomen whitish to light brown, terminalia light brown.

FIG. 7

Psyllipsocus spp. , female. A-E: Psyllipsocus serrifer Lienhard n. spec. (A) Spermathecal blade, base downwards directed in the figure, female from Doresópolis (MG). (B) Ditto, female from Pains (MG), Brasical cave. (C) Ditto, female from Pains (MG), Sobradinho cave. (D) Ditto, female from Matozinhos (MG). (E) Ditto, female from Januária/Itacarambi (MG). (F) Ditto, Psyllipsocus similis Lienhard n. spec. (G) Ditto, Psyllipsocus clunjunctus Lienhard n. spec. H-J: Psyllipsocus serrifer Lienhard n. spec. (H) Spermapore sclerite with insertion points of muscles. (I) Spermatheca, transition zone between duct and sac, with base of spermathecal blade. (J) Spermatheca containing one spermatophore. Scale bar = 0.1 mm (A-G).

FIG. 8

Psyllipsocus similis Lienhard n. spec., female. (A) Forewing. (B) Hindwing of the same specimen. (C) Spermapore sclerite, female allotype from Itambé do Mato Dentro (MG). (D) Ditto, female from Itabirito (MG). (E) Epiproct, paraprocts (slightly overlapping due to slidemounting), hind corners of clunium (arrows) and left ovipositor valvulae. (F) Spermatheca containing one spermatophore.

Both sexes macropterous (Fig. 8AB) or slightly brachypterous; in the forewing often some vein irregularities (e. g. Rs simple, M 2-branched). Three ocelli present; compound eyes of medium size in both sexes (IO/D 1.7-2.3). Antenna very long but usually damaged in preserved material.

Hypandrium (Fig. 9CD) uniformly setose except for the glabrous and medially membranous apical lobe (as shown in Fig. 5A for P. serrifer ); the latter only bearing a pair of short marginal setae; arrangement of the four dorsal placoid sensilla as shown in Fig. 9CD. Shape of postero-lateral sclerotizations of phallosome and medio-distal semi-membranous microstructures somewhat variable, probably partly depending on position after slide-mounting; elongate oval phallosomal lobules not posteriorly prominent, situated between the lateral sclerotized bulges, each lobule with 2-3 placoid sensilla (Fig. 9CD). Clunial bridge relatively simple, somewhat flexible in middle and on each side at narrowest part (Fig. 9E), on each side with a dorso-medially directed spur-like posterior prominence; central cavity laterally delimited by a rounded papillate border, these borders representing the ventralmost parts of the bridge (Fig. 9AE).

Spermapore sclerite (Figs 8CDF, 9B) of slightly variable shape and length, its anterior border asymmetrically lobate. Spermathecal blade slender, file-like, weakly sclerotized (Figs 7F, 8F). Spermathecal duct about twice as long than spermathecal blade (Fig. 8F), no distinct thickening observed near spermathecal sac. Spermatophore broadly rounded, not much more than twice as long as wide, pear-shaped (Fig. 8F; in the spermatheca of one female two spermatophores could be observed; this indicates that the species is polyandrous; see General Discussion, below).

MEASUREMENTS: Both sexes of about same size, body length 1.7-2.2 mm. Male holotype (slightly brachypterous): BL = 1.7 mm; FW = 1600 µm; HW = 1120 µm; F = 480 µm; T = 902 µm; hindtarsi broken; IO/ D = 2.0. – Female allotype (slightly brachypterous): BL = 1.7 mm; FW = 1640 µm; HW = 1080 µm; F = 475 µm; T = 917 µm; t1= 392 µm; t2 = 62 µm; t3 = 75 µm; IO/ D = 2.1. – Male paratype from Moeda (macropterous): BL = 1.8 mm; FW = 1960 µm; HW = 1500 µm; F = 458 µm; T = 846 µm; t1= 370 µm; t2 = 69 µm; t3 = 75 µm; IO/D = 1.7.

ETYMOLOGY: The specific epithet (Latin: similis , -is, -e; similar) refers to the similarity of this species to the two other species of the clunjunctus species group, especially concerning the characters of the hypandrium (similar to P. serrifer ) and of the clunial bridge and the spermathecal blade (similar to P. clunjunctus ).

DISTRIBUTION AND HABITAT: At present P. similis is only known from three quartzite and iron ore caves situated in three municipalities in south-eastern Minas Gerais (see Fig. 1). Since there are macropterous specimens, which can easily disperse by flight, this narrow distribution may indicate some habitat specificity for this species. The three caves are located at higher altitudes (from 750 to 1550 m a.s.l.) than most of the caves in which the other species of the clunjunctus group usually occur. This may indicate some habitat preference (e. g. for low temperatures) that may explain the distribution and rarity of this species.

DISCUSSION: P. similis can be distinguished from both other species by the irregular anterior margin of the spermapore sclerite, by the broadly rounded pear-shaped FIG. 9

Psyllipsocus similis Lienhard n. spec. (A) Male abdominal apex after separation of hypandrium, ventral view, slightly squashed, posterior part (i. e. paraprocts) upwards directed in the figure. (B) Spermapore sclerite, female paratype from Itambé do Mato Dentro (MG). (C) Hypandrium and phallosome, ventral view (phallosome observed through ventral wall of hypandrium, pilosity of basal part of the latter not shown), male from Moeda ( MG). (D) Ditto, male from Itambé do Mato Dentro ( MG). (E) Clunial bridge, posterior view. Same magnification for A-E .

spermatophore and by the presence of only two short marginal setae on the broad membranous and otherwise glabrous distal lobe of the hypandrium. Its file-like spermathecal blade and its simple clunial bridge are similar to the corresponding characters of P. clunjunctus . In P. similis general size and relative length of the spermathecal duct are intermediate between the other two species of the clunjunctus group. See also General Discussion, below.