Phallofractus thailandensis, García, Alfonso N., 2009

García, Alfonso N., 2009, New monotypic genera of Epipsocidae (Psocoptera: Epipsocidae) from Belize and Thailand, Zootaxa 1978, pp. 63-68 : 66-68

Phallofractus thailandensis sp. n.

( Figs. 6–12 )

Color (after 21 years in 80% ethyl alcohol). Body orange brown. Compound eyes black, ocelli hyaline, with thick, ochre centripetal crescents. Head pattern ( Fig.7 ). Maxillary palps and legs pale brown (antennal flagella missing). Wings hyaline, with a slight orange hue. Abdomen pale brown.

Morphology. As in generic diagnosis, plus the following. Outer cusp of lacinial apices broad, with eight denticles ( Fig. 9 ). Pretarsal claws slender, with a small preapical denticle ( Fig. 8 ). Forewing pterostigma long, wider in the middle ( Fig. 6 ). Areola postica long, approximately shaped like an scalene triangle ( Fig. 6 ). Hypandrium ( Fig. 11 ) broad,setose, rounded posteriorly, with one conspicuous field of three macrosetae on each postero-lateral corner. Phallosome ( Fig. 10 ). Paraprocts ( Fig. 12 ) robust, almost elliptic, with setae as illustrated and a field of small setae along posterior border, sensory fields large, elliptic, with 24–26 trichobothria issuing from basal rosettes. Epiproct ( Fig. 12 ) trapeziform, setae as illustrated, with a field of small setae along posterior border.

Measurements. FW: 3480, HW: 2584, F: 850, T: 1476, t1: 660, t2: 202, ctt1: 30, Mx 4: 230, IO: 279, D: 222, d: 145, IO/D: 1.25, PO: 0.653.

Material studied. Holotype male, THAILAND, Chiang Mai Province, Doi Suthep (Chiang Mai District) at 1180 m., 1–30.i. 1987 (P. Schwendinger). Deposited in the Muséum National D’histoire Naturelle, Genève, Suisse.

Etymology. The generic name is derived from the Greek, and means “fractured phallus”, in reference to the apical interruption of the aedeagal arch, resulting in two distinct arms. The specific name refers to the country of origin of this species.

Remarks. In a recent study on the phylogenetic relationships of the genera of Epipsocetae ( Casasola González 2006), the American epipsocid genera Goja Navás , Rogojiella García Aldrete and Ianthorntonia García Aldrete , grouped together in a clade, having as sister group an undescribed genus from Thailand, represented by one male. That male has here been described as Phallofractus ; it presents an autapomorphy that separates it from the other epipsocid genera: the aedeagal arch is apically interrupted, so there are two distinct arms, each associated with the side strut of the phallosome. Since it is the sister group to the cluster Goja , Rogojiella and Ianthorntonia ( Casasola González 2006) and since in the first and third of these genera the females are neotenic (females unknown in Rogojiella ), it is predictable that the female of Phallofractus be also neotenic.

Table 1 presents the distribution of eight character states in Phallofractus , Goja , Rogojiella and Ianthorntonia . The former genus differs from Goja in having caeciliusid venation, in having hindwing veins Rs-M fused, and in having the aedeagal arch incomplete. It differs from Rogojiella in having external parameres as membranous lobes, in having the aedeagal arch incomplete, in lacking a sclerotized band next each external paramere, and in having one pair of endophallic sclerites. It differs from Ianthorntonia in having wing venation caeciliusid, in having external parameres as membranous lobes, in having the aedeagal arch incomplete, and in having one pair of endophallic sclerites.

Figures

FIGURES 6 – 12. Phallofractus thailandensis sp. n. Male. 6. Fore- and hindwings. 7. Front view of head. 8. Pretarsal claw. 9. Lacinial tip. 10. Phallosome. 11. Hypandrium. 12. Clunium, right paraproct and epiproct. Scales in mm. Figures 8 – 9 to common scale. Figures 11 – 12 to common scale.