Fomoria festivitatis

Diagnostic description: 

Diagnosis. A typical fasciate nepticulid, relatively large, with collar composed of piliform scales, which can be confused with other fasciate Ectoedemia species, but E. festivitatis lacks all special scaling or hair pencils that occur in many other species. Externally similar Stigmella species can usually be recognised by a collar of lamellar scales. Male genitalia characterised by inner medial process of valva and very long curved ventral carinae; female genitalia by several sclerotizations in vestibulum.

Morphology: 

Male. Forewing length 1.8-2.9 mm (2.4 ± 0.3, 17), wingspan 4.0-6.1 mm. Head: frontal tuft orange to pale ochreous; scape cream with dark brown edge; collar consisting of piliform scales, same colour as frontal tuft; antenna greyish brown, 34-50 segments (44.4 ± 5.9, 14), longer than two thirds length of forewing. Thorax and forewing fuscous to black, with faint purple reflections; all scales darker at tips; postmedial fascia cream white, almost straight, slightly wider at dorsum, sometimes divided to almost obsolete; cilia line distinct; terminal cilia greyish white to grey. Hindwing and cilia greyish brown; no androconial scales; costal bristles present. Underside wings fuscous. Abdomen black, with very small grey anal tufts; abdominal tip tapering.
Female. Forewing length 1.9-3.1 mm (2.5 ± 0.3, 20), wingspan 4.1-6.6 mm. Antennae with 36-50 segments (43.1 ± 4.7, 14). Abdominal tip very broad, truncate. Otherwise similar to male.
Male genitalia. Vinculum with shallow anterior emargination; ventral plate posteriorly produced into a large bilobed juxta-like process, tightly fused to ventral carinae. Tegumen forming distinctly pointed pseuduncus, as long as uncus. Uncus with inverted Y-shaped medial process. Gnathos with relatively long narrow pointed central element. Valva narrow elongate to slightly triangular, medially with pronounced inner process in ventral plane; apex blunt. Transtilla with long transverse bar and relatively long sublateral processes. Aedeagus stout, with ventral pair of long, outward-curved carinae and dorsolateral pair of short, outward-curved carinae; vesica with groups of small blunt cornuti and two large cornuti near phallotrema, one straight, and one long curved, slightly sinuous, easily confused with carinae; a third one, proximal to the largest, a cone covered with small spines; cathrema conspicuous.
Measurements: capsule length 287-369 μm (327.5 ± 26.9, 7), valva length 204-228 μm (214.3 ± 10.7, 6), aedeagus length 253-387 μm (321.2 ± 45.5, 7), ratio aedeagus/capsule 0.8-1.1 (0.98 ± 0.09, 7).
Female genitalia. Abdominal tip: T8 broad and narrow, without any setae, posterior margin straight, with prominent rounded corners; T9: anal papillae each with ca 14-19 setae. Apophyses subequal in length, anterior apophyses curved. Bursa elongate, vestibulum with a number of strong sclerites, anteriormost a wide transverse bar, anteriorly covered with forward-directed spines (not seen in one specimen, 3814); bursa completely covered with pectinations, particularly strongly developed in folded ductus bursae, signa long and narrow 3-5 cells wide; ductus spermathecae with 2 shallow convolutions, ending in distinct vesicle.
Measurements: total length bursa 630-1160 μm (n=3), length of signa resp. 290-445 and 260-455 μm long (n=3).

Associations: 

Food plants. Shrubby species of Hypericum, reared from H. beanii N. Robson (Yunnan), H. henryi H. Lév. & Vaniot subsp. hancockii N. Robson (Vietnam); H. hookerianum Wight & Arn. (Vietnam) and H. uralum Buch.-Ham. ex D.Don (Nepal). These species have often been mixed in the literature and are difficult to distinguish, a recent treatment is Li & Robson (2007) in the Flora of China. Vacated mines on H. petiolulatum Hook.f. & Thomson ex Dyer subsp. yunnanense (Franchet) N. Robson in Yunnan, syntopic with mines on H. beanii, may also have been made by E. festivitatis. A distinct mine, probably belonging to this species, is shown on a photograph of H. oblongifolium Choisy, taken in India, Himachal Pradesh (Polunin & Stainton, 1984: plate 19, 210).
Egg deposited on under side of leaf, always near midrib. Leaf mine: starts as a very long, sinuous and very narrow gallery, often following leaf margin, with black to brown linear frass, abruptly widening into a blotch with scattered brown frass, usually concentrated in centre, adhering to upper epidermis. Later mine swollen and larva spinning cocoon inside a prepared silken tunnel, which leads to an exit slit, which the larva makes prior to spinning its cocoon.
Larva: greenish white with dark brown head capsule; feeding inside mine with venter upwards.
Habitat: secondary or degraded forest or shrub vegetation, in mountainous area.

Distribution: 

Distribution. Sino-Himalayan region: Nepal, China: Yunnan and North Vietnam (Fan Si Pan only). Probably more widespread, occurrence in India suggested by above cited photograph.

Life cycle: 

Life history. Voltinism: Larvae were collected in July and from September to early November and adults emerged under laboratory conditions in August, October and from January to March. E. fesitivitatis is bivoltine or has possibly more generations.

Citation: 

This taxonomic description is based on Van Nieukerken (2008).

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith