A new species of the genus Neosilba (Diptera: Lonchaeidae)
Author
Strikis, P. C.
Author
Prado, A. P.
text
Zootaxa
2005
828
1
4
journal article
10.5281/zenodo.170650
8b7b39df-a124-4b86-8a85-bd3d4602e0e9
11755326
170650
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
.
FIGURES 1–3:
1, Male terminalia in lateral view. 2, Male terminalia in ventral view. 3, Detail of male terminalia showing spinelike structure in ventral view.
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