Phyllonorycter melanosparta (Meyrick, 1912)

Prins, Jurate De & Kawahara, Akito Y., 2012, Systematics, revisionary taxonomy, and biodiversity of Afrotropical Lithocolletinae (Lepidoptera: Gracillariidae), Zootaxa 3594 (1), pp. 1-283 : 120-121

The melanosparta group

The melanosparta group includes three species: P. aarviki De Prins , n. sp., P. anchistea ( Vári, 1961) and P. melanosparta ( Meyrick, 1912a) . Adults belonging to this group can be easily distinguished from all other Afrotropical Phyllonorycter species groups by external characters. This is the only species group among Afrotropical Phyllonorycter with only dark fuscous markings on forewings without traces of white. Superficially, dark fuscous markings on forewings of the melanosparta species group can be confused with those of Cameraria hexalobina ( Vári, 1961) , however, the pattern and form of markings are different. The dark fuscous markings on forewings can be characterized as follows:

first marking from base is a costal strigula, slightly shorter than half of width of forewing, oblique towards apex;

second marking from base is a sharply angulated fascia;

third marking from base is the second costal strigula, running parallel to the first costal strigula;

the inverse Y on subapical part of forewing;

termen and apex irrorated with blackish fuscous scales.

Externally, species within the melanosparta group are hardly distinguishable. Minor differences are found in vertex coloration and in markings of tarsa. However, these superficial features can be detected only if the specimens are not worn. Dissections provide the only means for an accurate identification. Larvae of the melanosparta species group create abaxial tentiform mines on leaves of Fabaceae and Malvaceae .

The valvae of the melanosparta species group are broad, enlarged at the base and very narrow distally, tegumen long, narrow weakly sclerotized, transtilla complete, narrow. Sternum VIII moderately large, significantly tapering caudally to pointed apex.

Female genitalia in the melanosparta species group possess modified anterior apophyses. This diagnostic character easily separates them from the rest of the Afrotropical Phyllonorycter : inner cuticle appendages of sterigma act as short curved anterior apophyses. Ductus bursae of melanosparta species group is long and narrow, corpus bursae, very small—a slight enlargement of caudal region of ductus bursae or bulbed with clearly visible distinction between corpus and ductus bursae. Corpus bursae with one small signum or one round/oval signum plate with one small signum.

The most conspicuous synapomorphies for this species-group in relation to other Phyllonorycter groups are: (i) valva narrow distally, which can acuminate sharply into a spine-like apex, (ii) inner cuticular appendages acting as anterior apophyses in female genitalia.

The melanosparta species group is restricted to coastal areas of the Indian Ocean, stretching along the southeastern coast of Africa and reaching the Arabian Peninsula (Oman).

Key to males of melanosparta group based on genitalia

1. Valva broad at its base, sinuous along costal margin, strongly tapering beyond middle, apical half very narrow, transition between the broad basal part and narrow apical part smooth.................................................... 2

– Valva rounded or oval with a long dagger-like sacculus ( Fig. 240 )....................................... 42. aarviki

2. Transition from broad basal part to narrow apical part of valva gradual, apex of valva bifid, saccus short ( Figs 246, 248, 249 ). ....................................................................................... 44. melanosparta

– Transition from broad basal part to narrow apical part of valva with the sharp perpendicular declination, apex consisting of one unit, sharp and pointed, bearing long stiff bristle, saccus long ( Figs 243, 245 )4............................ 3. anchistea

Key to females of melanosparta group based on genitalia

1. Posterior apophyses straight or gently curved, anterior apophyses, as sterigmatic appendages, initiate at posterior sector of segment VII, corpus bursae drop-like, just a slight enlargement of caudal part of ductus bursae, one small sclerotized signum on corpus bursae, signa plate absent......................................................................... 2

– Posterior apophyses angulated, anterior apophyses, as sterigmatic appendages, initiate at subanterior sector of segment VII, corpus bursae round or slightly oval sac-shaped, with signa plate with signum ( Fig. 335 )................ 44. melanosparta

2. Anterior apophyses as sterigmatic appendages angulated, initiate at mid-sector of cone-like sterigma, antrum sclerotized, tubular, signum on corpus bursae tiny, pointed ( Fig. 334 )................................................ 43. anchistea

– Anterior apophyses as sterigmatic appendages gently bended, initiate at anterior margin of heavily sclerotized crescent-shaped sterigma, antrum not sclerotized, signum on corpus bursae small, heavily sclerotized, oval-shaped, with two tiny lateral barbs ( Fig. 333 ).................................................................................... 42. aarviki

Figures

FIGURES 240–242. Male genitalia. Scale bar 100 µm. 240–242, Phyllonorycter aarviki, paratype, genitalia prep. MRAC/ KMMA 00658, in RMCA. 240, ventral view. 241, sternum VIII. 242, aedoeagus.

FIGURES 246–251. Male genitalia. Scale bar 100 µm. 246–248, Phyllonorycter melanosparta, the drawing is made by Willy De Prins after the genitalia prep. Vári 6925, in TMSA. 246, lateral view. 247, aedoeagus. 248, valva. 249–251, Phyllonorycter melanosparta, genitalia prep. MRAC/KMMA 00377, in RMCA. 249, ventral view. 250, sternum VIII. 251, aedoeagus.

FIGURES 243–245. Male genitalia. Scale bar 100 µm. 243–245, Phyllonorycter anchistea, holotype, the drawing is made by Willy De Prins after the genitalia prep. Vári 7138, in TMSA. 243, lateral view. 244, aedoeagus. 245, valva.

FIGURES 334–335. Female genitalia. Scale bar 200 µm. 334, Phyllonorycter anchistea, paratype, the drawing is made by Willy De Prins after the genitalia prep. Vári 7139, in TMSA. 335, Phyllonorycter melanosparta, genitalia prep. MRAC/ KMMA 00374, in RMCA.

FIGURES 332–333. Female genitalia. Scale bar 200 µm. 332, Phyllonorycter loxozona, holotype, the drawing is made by Willy De Prins after the genitalia prep. 6110, in BMNH. 333, Phyllonorycter aarviki, holotype, genitalia prep. MRAC/KMMA 00370, in RMCA.