Indiopsocus mendeli Lienhard, 2011

Lienhard, Charles & Philip Ashmole, N., 2011, The Psocoptera (Insecta: Psocodea) of St Helena and Ascension Island (South Atlantic) with a new record from South Africa, Revue suisse de Zoologie 118 (3), pp. 423-449 : 441-444

Indiopsocus mendeli Lienhard sp. n. Figs 8-9

HOLOTYPE: MHNG, 3, Ascension Island, Devil's Cauldron , S7º56' W14º19', 12.viii.2003, leg. H. Mendel (off Juniperus bermudiana).

PARATYPES: BMNH, MHNG and SEHU, 193, 10♀ (one of them allotype, MHNG 8018 ), same data as for holotype . – BMNH and MHNG, 113, 8♀, Ascension Island, Mt Red Hill , S7º58' W14º21', 14.viii.2003, leg. H. Mendel (off Tecoma stans) . – BMNH, 13, Ascension Island, Mt Red Hill , S7º58' W14º21', 14.viii.2003, leg. H. Mendel. – BMNH, 1♀, Ascension Island, Devil's Ashpit , S7º57' W14º13', 2.viii.2003, leg. H. Mendel (vacuum sampler) .

DESCRIPTION: Colouration: Head and thorax pale brown, with dark brown markings, postclypeus with brown longitudinal stripes, antenna brown, compound eye black, legs yellowish to medium brown. Maxillary palp with P1 and P2 very light brown, P3 and P4 darker brown, apical half of P4 blackish brown. Forewing pattern slightly sexually dimorphic, with more extensive brown markings in female (Fig. 8f) than in male (Fig. 8a), especially in basal half of the wing. Abdomen whitish, with some red-brown hypodermal pigment, in particular laterally, terminalia dark brown. In male, membranous zone anteriorly to hypandrium on each side with a brown sclerotized patch (Fig. 9a), sometimes not very distinct.

Morphology: Compound eyes very large and prominent in male, distinctly smaller in female (see IO/D values, below), ocelli well-developed. Wing venation as in Fig. 8a, b, f; posterior apex of pterostigma with a very short and sometimes weakly developed spur vein.

Male terminalia (Fig. 9): Posterior margin of clunium medially slightly prominent and overlapping base of epiproct (Fig. 9d), the latter hemicircular, basally on each side with a well-sclerotized swelling (Fig. 9a, d). Paraproct with a short lateral protuberance, a pointed apical process and a small setose protuberance basally of the latter; trichobothria forming an arched, posteriorly open sense cushion (Fig. 9a, d). Medio-distal protuberance of hypandrium slightly asymmetrical, subdivided into a few pustulate or denticulate lobes, partly weakly but mostly heavily sclerotized (Fig. 9a, c). Phallosome basally broad and truncate, distally with a pair of lateral lobiform and weakly sclerotized processes and three well-sclerotized subacute apical processes of almost equal length, separated by two narrow V-shaped indentations (Fig. 9b).

Female terminalia: Posterior margin of clunium straight, epiproct and paraprocts simple, as usual in the family. Subgenital plate as in Fig. 8d, basal sclerotization

FIG. 8

Indiopsocus mendeli Lienhard sp. n.: (a) Forewing, male (scale bar: 1 mm). (b) Hindwing, male (to same scale). (c) Gonapophyses, female. (d) Subgenital plate, female. (e) Spermapore region, female. (f) Forewing, female (to same scale as Fig. 8a, b).

V-shaped, median zone of apical lobe particularly well-sclerotized on each side. Gonapophyses and region of spermapore as in Fig. 8c, e; posterior lobe of external valvula inconspicuous.

FIG. 9

Indiopsocus mendeli Lienhard sp. n., male: (a) Abdominal apex, lateral view (pilosity not shown, except for paraproctal trichobothria). (b) Phallosome. (c) Hypandrium, posterior view (slightly squashed). (d) Clunium, epiproct and paraprocts (dorsal view, pilosity partially omitted, paraprocts in different position).

MEASUREMENTS: Male holotype: BL = 2.0 mm; IO/D = 0.9; FW = 2.75 mm; F = 590 µm; T = 1200 µm; t1= 436 µm; t2 = 143 µm. – Female allotype: BL = 2.1 mm; IO/D = 1.7; FW = 2.95 mm; F = 590 µm; T = 1240 µm; t1= 414 µm; t2 = 144 µm.

ETYMOLOGY: The specific epithet refers to the collector of the type material, Howard Mendel ( BMNH), in recognition of his important contributions to scientific study of St Helena and Ascension Island fauna .

DISCUSSION: The new species is closely related to Indiopsocus dentatus ( Thornton & Woo, 1973) , which is only known from the Galapagos Islands ( Thornton & Woo, 1973; Lienhard & Smithers, 2002). The forewing pattern of the female of I. dentatus (see Thornton & Woo, 1973: fig. 77) is very similar to that figured here for the male of I. mendeli (Fig. 8a), while in the female of the latter some additional dark markings are usually visible in the basal half of the wing (Fig. 8f). Female genitalic characters of both species are very similar (see Thornton & Woo, 1973: figs 78, 79; the spermapore region of I. dentatus is not known). However, these species are easy to distinguish by the different shape of the apical lobes of the hypandrium and especially of the terminal processes of the phallosome (see Thornton & Woo, 1973: figs 80-82); in particular, the two deep indentations between the three mediodistal processes of the phallosome are broadly U-shaped in I. dentatus .

After the above treated Cerobasis maya this is the second example of apparent New World affinities in the Psocoptera fauna of Ascension Island (see also Biogeographical discussion).