Thaumatovalva Timm & Brown

Timm, Alicia E. & Brown, John W., 2014, A new genus of Grapholitini from Africa related to Thaumatotibia (Lepidoptera, Tortricidae), ZooKeys 438, pp. 113-128 : 114-118

Taxon classification Animalia Lepidoptera Tortricidae

Thaumatovalva Timm & Brown gen. n.

Type species.

Thaumatovalva albolineana Timm & Brown, new species.

Diagnosis.

Superficially, species of Thaumatovalva are highly uniform in forewing pattern and very similar to pale specimens of Thaumatotibia batrachopa (Meyrick) or Cryptophlebia rhynchias (Meyrick). They are easily distinguished from those and all other species of Thaumatotibia and Cryptophlebia by the modified scaling of the under surface of the hindwing in the male, the patterns of which are species-specific. In addition, males of all species of Thaumatovalva possess a row of long slender scales along the anal region of the hindwing that extends into a modified patch of scales on abdominal segment V; highly unusual, elongate, spindle-shaped scale clusters concealed within the last abdominal segment; and variously developed, parallel, longitudinal rows of black scales subdorsally on abdominal segments 4-6 (occasionally weakly developed on 3). The tegumen of the male genitalia of Thaumatovalva is completely confluent with a membranous region behind it, forming what appears to be an extremely broadly, ovoid dorso-anterior portion of the tegumen. The phallus of all species of Thaumatovalva have a variably developed, somewhat digitate lobe from the dorsum in the distal 0.3. The latter two features appear to be unique within Grapholitini .

Komai (1999) identified five adult characters that support the monophyly of the clade Thaumatotibia + Cryptophlebia : (1) forewing with a blackish triangular pretornal patch; (2) forewing with accessory cell small or absent; (3) hindwing with short discal cell, especially in male; (4) T8 and sometimes preceding tergites in male with patch of long, easily removable mane-like scales; and (5) valva with a patch of very long, curled scales on the outer surface of the cucullus. Among these characters, Thaumatovalva lacks the pretornal patch and the mane-like scales.

The male genitalia of Thaumatovalva , with their many autapomorphies (e.g., the complex tegumen, the triangular process from the sacculus of the valva, the lobe-like process of the phallus), all serve to obscure the relationship of Thaumatovalva to its nearest relative. The simple, unmodified female genitalia, likewise, provide little compelling evidence of the position of the genus. An abundance of different types of male secondary scales is common to many Grapholitini , including Cryptophlebia , Thaumatotibia , Talponia , and others, however, these structures rarely provide compelling evidence of relationships. For example, males of Multiquaestia Karisch have a fascicle of slender scales extending from the base of the hindwing to the abdomen (Aarvik and Karisch 2009: figs 3-4). Although males of Thaumatovalva have a similar complex of scaling, the dense fascicle of scales present in Multiquaestia is quite different from that of Thaumatovalva . In Thaumatovalva the narrow, linear patch of sparse scales originates all along a membranous line in the anal region of the hindwing and inserts into a poorly defined pouch laterally on the abdomen. Barcode data place Thaumatovalva nearest two undescribed species of Grapholitini that lack compelling generic assignments. Hence, this gene is of little value in helping define the position of Thaumatovalva within Grapholitini .

Description.

Head: Vertex and upper frons rough scaled, scales mostly directly anterad, lower frons smooth scaled, with small appressed scales (Fig. 1); antenna ca. 0.5 length of forewing, weakly serrulate, scales in two rows per segment, sensory setae extremely short, inconspicuous in both sexes; ocellus moderately large, diameter ca. 0.5 that of base of scape; labial palpus upturned, third segment somewhat porrect, exposed, all segments combined ca. 1.2 times horizontal height of compound eye; proboscis present, presumably functional. Thorax: Tegula simple, unmodified; metathorax with upraised scale tuft [inconspicuous in worn specimens]; hindleg with slightly expanded scale tuft on tibia in male only. Forewing length 5.0-8.2 mm; forewing broad, length about 2.4 times width, slightly broaden distally, apex somewhat rounded; no costal fold or upraised scales; all veins separate, CuP well developed at margin, chorda weak, accessory cell weak; forewing dark brown, irregularly and faintly mixed with specks of charcoal, rust, and cream; inconspicuous pair of tiny cream dots ringed with orange near distal end of discal cell; narrow cream (faintly mixed with brown) irregular band extending along termen from apex to ca. 0.66 distance to tornus. Fringe pale brown. Forewing under surface nearly uniform brown, paler than uppersurface. Hindwing with all veins present, M1 and M2 widely separated, M3 and M4 short-stalked, cubital pecten weak in male, better developed in female; frenulum with one acanthus in male, three in female; male with long slender scales (ca. 30-40) along middle 0.7 of anal margin (Fig. 2) extending to narrow groove on abdominal segment V (groove not evident on dissected integumen), dissection revealing that hairs insert beneath anterior edge of dense, linear patch of black sex scales subdorsally on abdominal segment V (Fig. 3); underside of hindwing between anal angle and CuP with variously modified secondary scales in male (Figs 10-13); distally forked scales along outer edge of hindwing, most conspicu ous in distal portion of anal margin (Fig. 5). Abdomen: Male with paired, parallel, thick, linear patches of black sex scales subdorsally on segments 4, 5, and 6 (easily lost during dissection) (Fig. 3); scales from anal margin of hindwing inserted into anterior edge of scale patch on segment V; dorsum of segment VIII of male with a narrow line of sclerotization and a weak stem from its middle; invaginated portion of segment VII of male with broad U-shaped sclerotized posterior edge bearing membranous lateral flaps to which a dense cluster (ca. 40-50) of highly modified, long, spindle-shaped male secondary scales are attached, and with rounded membranous mesal lobe (Fig. 4). Male genitalia (Figs 14-18) with uncus, socius, and gnathos absent. Tegumen broad, elongate-ovoid, confluent with membranous region behind it (anellus?), pedunculi not curved, vinculum small, U-shaped; valva narrow basally, broadening to middle, with (in spinai, albolineana, and deprinsorum) or without (in limbata) large, triangular expansion of valva along ventral edge just before cucullus, outer edge of cucullus evenly rounded, valva attenuate to acute, rounded apically; cucullus covered with fine hairline setae on outer surface; phallus narrow, relatively straight in basal portion, curved in distal portion, with bulbous subbasal lobe at point of articulation with phallus, with digitate subapical lobe of variable size; cornuti absent. Female genitalia (Figs 18-19) with papillae anales unmodified; apophyses long and slender, posteriores about same length anteriores; ventral portion of segment VII with a broad subrectangular sclerotized patch with V-shaped posterior edge and tiny ostium at apex of V, a short narrow trough from ostium to posterior edge of segment VIII; ductus bursae long, slender, frail, with ring-like sclerite near middle; corpus bursae pear-shaped, finely punctate (at high magnification), with two nearly equal size signa, each a long curved spine from a rounded sclerotized base.

Sexual dimorphism.

No apparent dimorphism in color or pattern, but females average slightly greater in forewing length and lack secondary scales on the under surface of hindwing, hind tibia, and abdomen.

Barcode data.

Eight (six reared from Kenya and two field-collected in Kenya) of the nine specimens have identical barcode data, and we assign them to Thaumatovalva limbata . All specimens resulted in standard 658-bp sequences. The reared specimens are considerably larger than the field-collected specimens, i.e., about the same size as Thaumatovalva limbata from the Seychelles, the type locality of the species. The ninth specimen, the holotype of Thaumatotibia spinai , shows about 1.0% divergence from the cluster of Thaumatovalva limbata .

Distribution and biology.

The genus is recorded from Ethiopia, Nigeria, the Democratic Republic of Congo, Kenya and the Seychelles (Map 1). Most species appear to occur in montane regions above ca. 1275 m, but Thaumatovalva limbata has been recorded from 35-1272 m; and a single specimen of Thaumatotibia spinai from Nigeria was collected at 54 m ( Razowski and Wojtusiak 2012). Although the early stages are unknown, the larvae are assumed to be fruit feeders, as are most Grapholitini . Thaumatovalva limbata (cited as Grapholita limbata by Brown et al. 2014) has been reared from the fruit of Cordia somaliensis and Cordia monoica in Kenya.

Etymology.

The generic name is from the Latin thaumato, meaning “miracle” or “wonder,” and the morphological term “valva.”

Key to the males of Thaumatovalva