Neosilba bifida Strikis & Prado, 2005, n. sp.
Creators: name: Strikis, P. C.
name: Prado, A. P.
Publisher: name: Zenodo
Year: 2005
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Lonchaeidae
Neosilba
Neosilba bifida

description: Neosilba bifida n. sp.
Material examined: Holotype: male, deposited in the Museu de Zoologia da Universidade de São Paulo, SP. Brazil; reared from Eriobotryia japonica (Thumb.) Lindl. (nêspera) São Bento do Sapucai­SP, Brazil, 31/01/1996, collected by Miguel de Souza Filho, kept in alcohol. Paratypes: 2, one kept in alcohol another mounted in microscope slide deposited in the Museum cited as above, derived from the same sample as the holotype.
Description Male: body size 5.0 mm. Frons narrowed toward lunule. Head length/ width ratio 1.17. Lunule with 8 setulae 4 at each side; ocellar plate with 5 strong bristles, and 2 strong inter ocellar bristles below ocellar plate and 2 others above ocellar plate. Antenna with one prominent bristle in the second segment, first flagelomere with length/ width ratio 3.72 (0.82 mm: 0.22 mm); arista long and plumose (1.05 mm), longer than first flagelomere; arista length/first flagelomere length ratio 1.28. Palpus large and broad.
Thorax: Mesonotum 1.6 mm long; anepisternum with 5 strong bristles and a cluster of 3 setae below the bristles. Scutellum margin bare, with 2 strong marginal basal bristles and 2 apical marginal bristles and a cluster of 4 marginal setae at each side and 2 setae between apical bristles; dorsum of thorax setulose with 12 strong bristles.
Wings: 4.7 mm long, hyaline, with brownish veins and microtrichias; length/width ratio 2.30; calypteres white with white fringes and with about 12 long blackish setae at fold.
Male terminalia: Epandrium short; as long as wide (1:1); in lateral view surstylus is not visible, and has 6 prensisetae. Aedeagus filament fine and slender after “C” shaped base until apex, ending just after prensisetae and evenly tapered to apex (Fig.1). “C” shaped base of aedeagus with no spicules but with a remarkable spine­like left bended structure in ventral view, arising from the distal portion of convex side of the “C” shaped base of aedeagus (Fig.2 and 3). There may be some variation in length of the spine­like structure
Female: unknown.
Diagnosis: the most remarkable character in identifying N. bifida n. sp. is the spinelike structure, which is easily seen in ventral or lateral view of male terminalia.
Taxonomic discussion: N. bifida n. sp. is very similar to N. glaberrima McAlpine & Steyskal externally, but lacks the hair arrangement in the last abdominal tergite; we believe it belongs to a group of undescribed species that has a complex structure in the convex side of the “C” shaped base of aedeagus, ending with the formation of a well defined spine­like structure.
Distribution: Only known from São Bento do Sapucai, São Paulo, Brazil; this locality situated over 900 meters height.
Biology: This species has been reared from Eriobotryia japonica (nêspera), and just a few individuals were collected from this fruit.
The inclusion of N. bifida in McAlpine’s (1982) key to Neosilba species is suggested as follow:
6. Aedeagus short and broad, (Figs. 29–30, 34–35). Prosternum usually setulose .......... 7 Aedeagus slender. Prosternum always bare ................................................................. 8 8 Aedeagus with a median lobe or a pair of teeth on thicker basal section, apex of filament not swollen or strongly S shaped ........................................................................ 9 8’ Aedeagus with a spine­like structure arising from the distal portion of the convex side of the “C”shaped base, short and slender and two times as long as the “C” shaped base ...................................................................................................................... bifida n. sp.
8’’ Adeagus without a median of lobe or a pair of teeth on thicker basal section, apex of filament frequently swollen, flared or S shaped ......................................................... 11
description: Published as part of Strikis, P. C. & Prado, A. P., 2005, A new species of the genus Neosilba (Diptera: Lonchaeidae), pp. 1-4 in Zootaxa 828 on pages 2-4, DOI: 10.5281/zenodo.170650