Psyllipsocus thaidis Lienhard, 2014

Lienhard, Charles & Ferreira, Rodrigo L., 2014, New species of Psyllipsocus from Brazilian caves (Psocodea: ‘ Psocoptera’: Psyllipsocidae), Revue suisse de Zoologie 121 (2), pp. 211-246 : 223-225

Psyllipsocus thaidis Lienhard n. spec. Fig. 7

HOLOTYPE: ISLA; ♀ (slide-mounted); BRAZIL ( PI), Coronel José Dias , Coroa de Frade cave, ix.2008, leg. R. L. Ferreira.

DESCRIPTION OF FEMALE: General colouration light brown. Forewing with a characteristic colour pattern (Fig. 7A), hindwing hyaline (Fig. 7B). Head with some brown patches (Fig. 7H); compound eyes dark brown. Legs light brown, lacking any patches or transversal bands. Abdomen whitish with narrow red-brown transversal bands (more distinct laterally than dorsally), terminalia light brown.

Macropterous (Fig. 7AB). Forewing: Rs and M not fused for a length but joined by a crossvein (thus distal closed cell pentagonal); basal closed cell very much longer than distal closed cell (bcc/dcc ≈ 5.5), the latter also shorter than marginal length of pterostigma; first portion of pterostigmal R1 almost parallel to wing margin, slightly shorter than R1-Rs crossvein; CuA1 strongly curved, AP relatively short and high. Hindwing (Fig. 7B): R1 originating basally of Rs-M fusion, thus closed cell quadrilateral. Three ocelli present (Fig. 7H). Head pilosity not uniform, with numerous stout setae on vertex and frons in addition to normal thinner hairs (Fig. 7H: alveoli of dislodged stout setae shown and two stout setae, one of medium length, one of maximal length). Antennal flagellomeres with uneven surface (due to insertion points of long and relatively thick setae), in basal half of antenna maximal length of flagellar hairs about 5x greatest width of their flagellomeres. Pedicellar microspades organ weakly developed, with 2 units. P2 with a well-differentiated stout sensillum; P4 slender hatchet-shaped (Fig. 7D). Lacinial tip as in Fig. 7C. Pretarsal claws simple, symmetrical, with a small preapical denticle; hind legs with well-developed coxal organ.

Clunium, epiproct and paraproct simple, chaetotaxy of paraproctal hind margin as in Fig. 7E, paraproctal sensorium with six fine trichobothria on weakly differentiated basal florets and one normal seta. Subgenital plate simple, with a row of six long fine setae on posterior margin. Ovipositor valvulae as in Fig. 7F, v1 and v2 each with a weakly sclerotized median axis. Spermatheca as in Fig. 7G, empty (no spermatophore observed); spermathecal wall near duct with some complicated sclerotized yellowish structures; spermapore plate simple and membranous.

MEASUREMENTS: Female holotype: BL = 1.8 mm; FW = 2010 µm; FWw = 790 µm; FW/FWw = 2.54; HW = 1636 µm; F = 338 µm; T = 712 µm; t1= 254 µm; t2 = 49 µm; t3 = 62 µm; IO/D = 1.7.

ETYMOLOGY: The species is named after Thais Oliveira do Carmo in recognition of her work on Brazilian cave psocids. The species epithet is invariable, it corresponds to the genetive case of the classical Greek name Thais.

DISTRIBUTION AND HABITAT: Psyllipsocus thaidis is only known from the type locality, the Coroa de Frade cave situated in Coronel José Dias municipality, Piauí state. This limestone cave is located in a semi-arid biome, called Caatinga. The external area was severely altered in the past decades by mining activities, which partially destroyed the entrance. Fortunately, the inner portion of the cave is isolated from the external environment by a constriction of the conduit near the entrance. The specimen was found on a relatively old pile of bat guano. Although there are caves and rock shelters in the entire area, most of them are in sandstones or conglomerate strata. Some FIG. 7

Psyllipsocus thaidis Lienhard n. spec., female holotype. (A) Forewing. (B) Hindwing. (C) Lacinial tip. (D) P2-P4 of maxillary palp. (E) Hind margin of paraproct. (F) Right ovipositor valvulae. (G) Spermatheca. (H) Front view of head, showing frontal and vertical pigmentation and alveoli of particularly stout setae (alveoli of thinner hairs not shown).

of these caves were surveyed but P. thaidis was not found, perhaps indicating some habitat preference of this species.

DISCUSSION: Psyllipsocus thaidis belongs to a small group of species also comprising P. falcifer and P. marconii . Among Brazilian Psyllipsocus these species are characterized by the apomorphic presence of a Rs-M crossvein in the forewing. While P. falcifer has unmarked forewings, the other two species are clearly recognizable by their characteristic wing pattern. P. thaidis is also characterized by the presence of numerous stout setae on frons and vertex. The alveoli of these setae are clearly larger than those of normal setae (Fig. 7H, alveoli of normal setae not shown in this figure). Among Brazilian Psyllipsocus a similar non-homogeneous head pilosity has also been observed in P. subtilis and P. fuscistigma . In P. falcifer and P. marconii the head pilosity is almost uniform, lacking particularly thick setae on frons and vertex (often most setae dislodged in preserved material, but all alveoli relatively small and of almost equal diameter).