Tinkerbella Huber & Noyes, 2013

Huber, John T. & Noyes, John S., 2013, A new genus and species of fairyfly, Tinkerbella nana (Hymenoptera, Mymaridae), with comments on its sister genus Kikiki, and discussion on small size limits in arthropods, Journal of Hymenoptera Research 32, pp. 17-44 : 18-21

Tinkerbella Huber & Noyes gen. n.

Type species:

Tinkerbella nana Huber and Noyes.

Derivation of genus name.

After the fairy Tinker Bell in the 1904 play "Peter Pan" by J.M. Barrie. Gender: feminine.

Diagnosis.

Tinkerbella is defined by the following combination of features: body length at most about 250 μm; female antenna with funicle 5-segmented and clava entire ( Figs 1 , 3 , 5 , 13 ), compound eye with about 50 ommatidia ( Figs 11, 13 ), and tarsi 4-segmented ( Fig. 22 ).

Kikiki is the most closely related genus to Tinkerbella . It is distinguished from Tinkerbella by the following combination of features: female with funicle 4-segmented and clava 2-segmented ( Figs 24 , 37, 38 ), compound eye with about 20-25 ommatidia ( Figs 24 , 38, 39, 40 ), and tarsi 3-segmented ( Fig. 47, 48 ).

Description.

Female. Body minute, at most about 250 μm long. Head in dorsal view ( Fig. 12 ) about 1.6 × as wide as long, in lateral view ( Fig. 11 ) about 1.6 × as high as long, and in anterior view ( Figs 5 , 9 ) about 1.3 × as wide as high. Face slightly longer than wide and ventrally separated from clypeus by curved epistomal sulcus. Toruli about their own diameter from transverse trabecula. Clypeus apparently extending entire width of mouth opening, with anterior tentorial pits visible, slit-like ( Fig. 10 ). Mandible with 4 teeth, the lower one more distinct than the upper three ( Fig. 10 ). Eye with about 50 facets, in lateral view about 1.4 × as high as long and not extending to back of head dorsally. Malar distance about 0.4 × eye height, with straight malar sulcus. Vertex at about right angle to face above toruli, with supraorbital trabecula divided medially into two parts. Ocelli in normal triangle with POL: LOL: OOL about 1.1: 0.5: 0.5, enclosed by conspicuous rectangular stemmaticum and with sulci extending laterally to endpoints of posterior section of supraorbital trabecula ( Fig. 12 ); occiput divided by transverse sulcus just dorsal to foramen medially and ventral to eyes laterally ( Fig. 17 ). Antenna. Scape about 3.9 × as long as wide, with faint longitudinal reticulations on outer surface and distinct transverse ridges on inner surface ( Figs 5 , 13 ). Pedicel about 0.2 × as long as scape. Funicle 5-segmented. clava entire (a faint, partial division visible, however) ( Figs 5 , 13 ). Mesosoma. About 1.34 × as long as high and about 1.3 × as long as wide. Pronotum thin, in dorsal view scarcely visible ( Fig. 7 ), in lateral view with large lateral panel extending posteriorly to level of wing base ( Fig. 11 ). Mesoscutum ( Figs 16, 17 ) slightly longer than scutellum, with deep notauli. Anterior scutellum and axilla completely separated by deep straight transverse sulcus from slightly longer, longitudinally divided frenum. Second phragma projecting to apex of propodeum. Metanotum with dorsellum distinct, about 0.5 × as long as frenum, apparently divided by a median longitudinal groove ( Figs 16, 17 ), and much wider than very narrow lateral panel of metanotum ( Figs 16, 17 ). Mesopleuron ( Fig. 17 ) divided by fairly straight, faint transepimeral sulcus into narrower mesepisternum and wider mesepimeron. Metapleuron triangular. Propodeum in dorsal view ( Fig. 16 ) with anterodorsal area mostly smooth, posterodorsal area with minute rounded spicules medially, with propodeal seta about midway between spiracle and posterior margin of propodeum; in lateral view ( Fig. 18 ) strongly sloping. Propodeal spiracle circular, smaller than pronotal spiracle and distinctly separated from anterior margin of propodeum. Wings. Fore wing ( Figs 6 , 8, 20) narrow, almost parallel sided, with posterior margin distinctly concave beyond pronounced lobe ( Fig. 21 ) at level of parastigma; wing surface bare except for fewer than about 10 scattered microtrichia on dorsal and ventral surfaces; fringe setae much longer than wing width. Venation extending almost 0.7 × fore wing length; submarginal vein about 1.6 × parastigma length, and parastigma about 0.5 × marginal + stigmal vein lengths (their relative proportions about 24/15/29); hypochaeta close to proximal macrochaeta ( Fig. 21 ); parastigma with distal macrochaeta about 3 × as long as proximal macrochaeta ( Fig. 21 ). Hind wing ( Figs 6 , 8 ) curved, with anterior margin concave, paralleling convex posterior margin, apex bluntly rounded, with long fringe setae at apex and along posterior margin to just beyond level of relatively large hamuli; wing surface bare except for row of fewer than about 8 microtrichia along anterior margin except toward hamuli where they are located more posteriorly. Legs. Tarsi 4-segmented, tarsomere 1 slightly shorter than remaining tarsomeres, and tarsomere 4 distinct, as long as tarsomere 3 ( Fig. 22 ). Metasoma. Slightly shorter than mesosoma (critical point dried specimens) ( Fig. 7 ); petiole very short (scarcely visible), about 4.3 × as wide as long, but clearly narrower than gt1; gaster in dorsal view distinctly narrower anteriorly than medially ( Fig. 7 ) with gt6 the longest tergite and apparently without a spiracle. Ovipositor ( Figs 7 , 18 ) as long as gaster, slightly exserted beyond gastral apex. Cerci with 3 long setae extending just beyond ovipositor apex ( Fig. 19 ).

Male. Antenna 11-segmented ( Fig. 14 ), with 2 mps each, except fl3 and fl5 much shorter and without mps ( Fig. 15 ), the mps decreasing in width on each segment, from almost circular on fl1 to linear on fl11.

Figures

Figures 1, 2. Habitus, lateral. 1 Tinkerbella nana female 2 Kikiki huna, female. Scale line = 100 μm.

Figures 3, 4. Tinkerbella nana female. 3 holotype, uncleared on slide 4 paratype, critical point dried on card. Scale line = 100 μm.

Figures 5 - 7. Tinkerbella nana female paratype, cleared on slide. 5 head + right antenna, anterior 6 wings 7 mesosoma + metasoma dorsal, and ovipositor ventral (inset). Scale line = 100 μm.

Figures 8 - 15. Tinkerbella nana paratype female (except 14, 15), micrographs. 8 habitus, lateral 9 head, anterior 10 mouthparts, anterior 11 head + pronotum, lateral 12 head, dorsal 13 head + antennae, lateral 14 male antenna, dorsal 15 male antenna, pedicel-fl 8, dorsal. Scale line = 20 μm, except Fig. 8 = 100 μm.

Figures 16 - 22. Tinkerbella nana female paratype, micrographs. 16 mesosoma, dorsal 17 mesosoma + back of head, dorsolateral 18 metasoma, lateral 19 apex of gaster, dorsolateral 20 wings (left wing ventral surface, right wing dorsal surface) 21 wing, basal half 22 left mesotarsus. See appendix for abbreviations. Scale line = 20 μm, except Fig. 20 = 100 μm.

Figures 23 - 26. Kikiki huna female, on slide (cleared, except Fig. 23). 23 habitus, dorsal 24 head + right antenna, anterior 25 head, posterior 26 mesosoma, dorsal + metasoma, dorsal but focus at lower plane to show ovipositor. Scale line = 100 μm.

Figures 36 - 42. Kikiki huna female, micrographs. 36 habitus, dorsal 37, head + antennae, anterior 38 habitus, lateral 39 head, lateral 40 head + anterior mesosoma, dorsolateral 41 head + base of antenna, dorsal 42 head, posterodorsal + anterior mesosoma, dorsal. Scale line = 20 μm, except 36, 38 = 100 μm.

Figures 43 - 48. Kikiki huna, female, micrographs except Fig. 47. 43 antenna, lateral 44 mesosoma, dorsal 45 frenum - anterior half of metasoma, dorsal 46 metasoma, dorsal 47 hind leg, uncleared lateral, showing muscles; 48, right metatarsus, dorsal. Scale line = 20 μm, except Fig. 47 = 50 μm and 48 = 10 μm.