Sphaeropsocus künowii Hagen, 1882: 226

Grimaldi, David & Engel, Michael S., 2006, Extralimital Fossils of the ‘‘ Gondwanan’ ’ Family Sphaeropsocidae (Insecta: Psocodea), American Museum Novitates 3523 (1), pp. 1-20 : 5-8

Sphaeropsocus künowii Hagen, 1882: 226 . In Baltic amber.

Name emended to kuenowii in accordance with ICZN (1999: Art. 32.5.2.1).

Atropos succinica Hagen, 1882: 231 . Synonymy vide Pearman, 1958: 51.

Troctes succinicus (Hagen) ; Kolbe, 1883: 190.

Palaeotroctes succinicus (Hagen) ; Enderlein, 1911: 350.

Sphaeropsocus künowi Enderlein, 1911: 352 . Lapsus calami pro Sphaeropsocus kuenowii Hagen, 1882 .

DIAGNOSIS: As for genus (vide supra).

DESCRIPTION: (Female) (measurements based on KU B-144): Minute psocopteran, body length sans forewings ca. 0.60 mm, with forewings 1.0 mm. Head: Prognathous; broad, width 0.8X the length. Anterior tentorial pits short, sulcuslike, convergent just above clypeus; tentorium well-developed, with tentorial bridge and anterior tentorial arms; median ‘‘coronal suture’’ extended from posterior margin of head to level of eyes. Ocelli absent. Compound eyes small, with seven facets not contacting each other. Clypeus of modest

3 The name Nanopsocetae was first established by Pearman (1936) and not by Broadhead (1950) as widely cited by many authorities.

4 The difficulty of paraphyly of Psocoptera, Troctomorpha, and Nanopsocetae with respect to the true lice could be easily obviated by the demotion of Phthiraptera to a category within the infraorder Nanopsocetae and the reduction of its constituent suborders to more subordinate categories. The family-group classification of the lice would be entirely unaffected. This would certainly be preferable to the splitting of Psocoptera into innumerable new orders, would minimize the number of taxonomic changes (only five changes), and would permit the reflection of hierarchical relationships in the classification of ‘‘higher’’ Psocodea . Such a classification should be seriously considered by louse systematists.

size; mandibles large; labial palps highly reduced (pair of small 1-segmented polyps on anterior margin of labium), area between labium and occipital foramen membranous. Maxillary palps 4-segmented, lengths of segments (longest to shortest): P4-2-3-1. Apical palpomere (P 4) spindle-shaped, apical half with oval sensillar area on ventral surface. Right lacinia protrudent, apex with one small and two large teeth. Antenna length 10.5 mm; scape and pedicel twice width of flagellomeres, approximately half the length of basal flagellomere. Flagellum with 13–14 articles, each flagellomere with fine annuli, and all but basal flagellomere with sparse setulae.

Thorax: Short, dorsally with only pronotum and mesoscutum exposed. Legs of moderate length, ca. 0.60–0.65 mm. Coxae large, opposites of each pair nearly touching medially; procoxae larger than metathoracic pair. Femora thick, width of profemur 3.5X width of protibia, of metafemur 2.7X width of metatibia; profemoral length 0.18 mm; metafemoral length 0.25 mm. All tibiae approximately equal in length (0.20 mm) and width; no apical spurs present. Tarsi trimerous, total length 0.13 mm; basal tarsomere slightly longer than others; pretarsal claw with preapical tooth. Wings: Forewings present only (hind wings absent); forewing elytrous, carapacelike, length 0.67 mm, greatest width 0.38 mm; anterior margin cordate. Surface of wing between veins areolate, with dense, irregular depressions. Venation highly reduced, consisting of: circumambient C, R and Rs, MA and MP, Cu, and very short A (for proportions see fig. 3). Stem of R and M very short, but length variable even between wings of same specimen. Surface of veins minutely papillate, devoid of areolae. Apices of veins not reaching margin of wings. Outer margin of wing with row of minute, stiff setulae. Wings meet in straight line for approximately half their mesal length; divergent mesally in apical half.

Abdomen: Short, globose, approximately same size as head, dorsally obscured by forewings, ventrally exposing little or very obscure segmentation. Apical half of abdomen ventrally covered with large subgenital plate; plate with posterior margin entire (not bilobed or emarginate). In KU B-144 subgenital plate lifted, exposing what appears to be two opposing brushes of fine setulae and pocked surface of cuticle.

HOLOTYPE: MCZ 235 (fig. 2a), ‘‘no. 103’’ in handwriting [presumably Hagen’s]. Specimen was preserved in a square chip of amber that was heavily crazed and darkened to a very deep red from years of exposure (it was originally mounted between a piece of folded paper that was then pinned, and may have originally been stored in a pinned collection). The piece was embedded in epoxy at the AMNH and ground and polished in order to expose fresh surface for viewing critical details.

ADDITIONAL MATERIAL EXAMINED: KU B- 144, -148, -154, all of which are preserved in middle Eocene Baltic amber from Germany, as well as a specimen preserved in Late Eocene amber from the Rovno region of the Ukraine ( Engel and Perkovsky, 2006a, 2006b).

COMMENTS: This species has been referred to frequently in literature on insect fossils, and illustrations of it often reproduced and refigured (e.g., Badonnel, 1951; Carpenter, 1992) (fig. 1). Despite this, and the fact it is not particularly rare in Baltic amber, this intriguing species has never been redescribed in detail. We have found that Hagen’s original illustration (fig. 1a) and description are remarkably accurate, which we can modify only slightly. The short vein A of the forewing is not present in the type specimen, and in other specimens A branches off at the very base of the stem of M + Cu, not off of Cu as depicted by other authors. Also, the longitudinal veins are incomplete and do not reach the wing margin.