Gibbalaria Brown and Aarvik, 2023

Brown, John W., Aarvik, Leif & Timm, Alicia, 2023, Gibbalaria: A new genus of Olethreutini from the Afrotropical Region (Lepidoptera: Tortricidae: Olethreutinae), and a new combination in Cosmopoda Diakonoff, Zootaxa 5263 (2), pp. 217-239 : 220-224

Gibbalaria Brown and Aarvik , new genus

Type species: Sericoris scabellana Zeller, 1852 .

Diagnosis. Species of Gibbalaria are superficially similar to those of Thylacandra Diakonoff (Grapholitini) and Astronauta Diakonoff (Olethreutini) , with a broadly triangular forewing that is mottled dark brownish black, lacking distinct pattern elements, and bears small rounded patches of curled or raised opalescent scales. The forewing pattern of Gibbalaria is also quite similar to that of Taiteccopsis Razowski , but the latter lacks raised scales. Males of five of the eight recognized species of Gibbalaria bear a characteristic patch of dark androconial scales on the underside of the hindwing—a feature lacking in putatively related genera. Gibbalaria is also superficially similar to the Indo-Australian Diakonoffiana Koçak , but the female genitalia have little in common—two large hollow signa in Diakonoffiana vs. a small reticulated area with a shallow pocket in Gibbalaria .

Two species of Gibbalaria (i.e., G. occidentana and G. chiloanei ) show some similarities to Cosmopoda in regards to the male genitalia, with a distinctive elongate-rectangular uncus and a patch of exceedingly long setae from the junction of the cucullus and the sacculus. Although the female genitalia of these two species of Gibbalaria convincingly associate them with Gibbalaria , the female of Cosmopoda is unknown, so the relationship between the two genera remains unclear. The small diverticulum of the ductus bursae of females of Gibbalaria is somewhat reminiscent of that of Astronauta sinastra Razowski & Wojtusiak, 2012 (see Razowski & Wojtusiak 2012: fig. 59).

The male genitalia of most Gibbalaria are similar to those of Afroploce Aarvik ( Neopotamia group of Olethreutini), with the valva composed of a broad basal half and a somewhat long-rectangular distal half, with a pair of large, socketed spines near the outer edge of the valva just beyond the sacculus; a distinct subbasal process from the costa of the valva usually bearing spines; and the bases of the socii confluent with the dorsal part of the tegumen, often forming a distally attenuate, membranous, uncus-like structure. However, the two genera are superficially very dissimilar. The forewing pattern of Afroploce is most similar to that of many species of Megalota and Eccopsis of the Neopotamia group (sensu Diakonoff 1973; Aarvik 2004b), and the forewing lacks raised scale patches. Also, males of Afroploce have a long anal roll of secondary scales at the base of the hindwing that is found in many Olethreutini, but lacking in Gibbalaria . The female genitalia of Gibbalaria share some features with members of the Neopotamia group (sensu Diakonoff 1973; Aarvik 2004b), but the signum is unlike members of the group, reminiscent of that of Endothenia . That is, females of Gibbalaria typically have a patch of small rough sclerites surrounding a shallow invaginated pocket.

Description. Head: Vertex with a pair of subdorsal patches of long gray and pale brown scales meeting along longitudinal line at mid-vertex; upper frons rough scaled with bronze and gray scales directed ventro-anterad; lower frons with smooth, appressed, dark gray scales; labial palpus upturned with pale brown scales, third segment short, barely exposed, all segments combined ca. 1.2 times horizontal height of compound eye; haustellum present, presumably functional; ocellus small, diameter ca. 0.1 that of base of scape; antenna slightly longer than 0.5 forewing length, pale orange scales in one row per segment, sensory setae extremely short in both sexes. Thorax: Tegula conspicuous; a pair of small, bronze metathoracic tufts in both sexes; male hindleg with broad brush of white scales from femur and second longer hair pencil from tibia just before junction with femur; venter of thorax mostly white, with white hair pencil from subdorso-anterior edge of mesothorax; legs mostly pale brown. Forewing length 5.5–8.5 mm, broad, about 2.1 times as long as wide, weakly expanding terminad; costa evenly arched throughout, apex slightly rounded, termen straight or slightly convex ( Figs 1–18 ); no costal fold in male; all veins separate, CuP well developed at margin, chorda present, M-stem present; forewing ground color gray brown to purplish gray, with irregular streaks of darker brown, red brown, and gray, with small, somewhat evenly spaced patches of raised leaden gray opalescent scales curled distally, but modified scales lacking in distal 0.25 of wing, mostly pale ocherous with an oblong spot of ground color at apex and irregular patch of cream or white scales extending from hind margin immediately before tornus to about end of discal cell; small, purple-black basal patch. Fringe concolorous with forewing. Hindwing usually whitish, more or less evenly overlaid with darker gray, including fringe, in male; mostly brown to fuscous gray, including fringe, in female ( Figs 7 , 11, 13, 15 ); males with irregularly rounded to subrectangular patch of pale gray to dark gray (nearly black) scales near middle of wing on underside ( Figs 16–18 ) (lacking in G. occidentana and G. chiloanei ); all veins present, M 1 and M 2 widely separated, M 3 and M 4 connate, CuA2 originating about 0.7 length of discal cell, cubital pecten present in both sexes, patch of longer, slender scales along most of 1A+2A. Fringe pale gray to brown, mostly concolorous with forewing; scales in anal area of male conspicuously larger and white, rounded apically; scales in anal area of female brown, narrower, forked apically. Abdomen: Pale gray dorsally, white to cream ventrally; smooth scaled without external modification. Male genitalia ( Figs 19–29 ) with uncus variable among groups, short, attenuate fused with base of socius, lacking setae apically, or long, broad, expanding terminad, concave apically with patch of long slender spines; socii fused to tegumen throughout their length, including basal portion of uncus, which appears to represent a dorsal extension of the fused bases of the socii; gnathos weak; tegumen triangular, either attenuate or broadly rounded dorsally, pedunculi not curved, vinculum U-shaped; valva broad basally, abruptly narrowed at middle, distal 0.5 nearly uniform in width, somewhat long-rectangular; sacculus with broad flange in distal 0.3, with patch of variable hairlike setae (Spc 2), usually with a pair of large socketed spinelike setae (Spc 1) at distal termination of sacculus; basal cavity broad with small setose prominence subdorsally just beneath a lobe-like, protruding, setose flange forming baso-dorsal margin of basal cavity; cucullus occupying distal 0.5 of valva. Phallus ca. 0.5 length of valva, weakly curved in distal 0.2, with patch of 2–6 non-deciduous cornuti (variable within and among species), one cornutus with a broader rounded base. Female genitalia ( Figs 30–36 ) with papillae anales mostly parallel-sided, unmodified; apophyses long and slender, anteriores slightly longer than posteriores; sterigma moderate, triangular or semicircular, in form of two lateral plates extending from elongate dorsal part, with sclerotized edges in postvaginalis; ostium large; antrum broad with two lateral dilations, sclerotized, asymmetrical, either parallel-sided or weakly expanded anteriorly; ductus bursae membranous, conspicuously elbowed with short diverticulum on left side immediately anterad of antrum, remainder narrow, frail; corpus bursae rounded-oblong; signum a large, coarse, pocketlike scobinate plate, often with a single longer tooth.

Sexual dimorphism in most species is slight. Females lack the male secondary scaling of the hindwing undersurface and scale pencils of the hind tibia. Also, in the female, the pale markings in the terminal region of the forewing typical of males are overscaled with darker scales, rendering an overall more uniform darker appearance; and females have a much darker brown hindwing.

DNA barcodes. Sequence data are available for five of the eight species provisionally assigned to Gibbalaria . Both ML and Bayesian trees ( Figs 1 , 2 ) provide evidence that Gibbalaria is monophyletic, comprising two distinct lineages, consistent with morphology: one that includes G. divergana , G. occidentana , and G. chiloanei , and the other that includes the remaining species. The analyses also suggest a close relationship with Eccopsis , but with less support.

Relationships. Although Diakonoff (1973) transferred sistrata to Celypha in the subtribe Olethreutae (based on the male only), Gibbalaria appears to be related to members of Neopotamiae ( Diakonoff 1973, Aarvik 2004b) on the basis of features of the male genitalia, but closer to Endothenia based on the signum in the female genitalia. The male genitalia and barcodes indicate a close relationship to Afroploce among members of the Neopotamia group. Autapomorphies of the genus include the patches of raised scales of the forewing, the patch of male secondary scaling on the underside of the hindwing (absent in three species), the fusion of the socii to the basal part of the uncus (absent in two species), the flange from the lower margin of the valva immediately basal of the cucullus, and the short diverticulum of the ductus bursae.

Distribution and Biology. As presently defined, Gibbalaria includes eight species recorded from South Africa, Tanzania, Malawi, Zimbabwe, Cameroon, Kenya, Gabon, and the Democratic Republic of Congo, occurring from near sea level in the Western Cape Province of South Africa to about 1600 m in KwaZulu-Natal Province, South Africa. The early stages are unknown.

Etymology. The generic name is from the Latin “gibba,” meaning bump or hump, and “alar,” meaning wing, and refers to the raised scales of the forewing. It is interpreted as feminine.

Remarks. Subtle variation in features of the male and female genitalia within and among some of the species are difficult to quantify, making it challenging to precisely circumscribe some taxa. In addition, DNA barcode data show patterns of divergence that are difficult to associate with morphology. Hence, some of the species defined herein may represent species complexes (e.g., G. scabellana ), and the proposed synonymies are not beyond question. For example, although the genitalia of two male specimens included in G. chiloanei show variation which we consider to represent species-level differences, DNA barcodes convincingly place the two together in the same BIN, as conspecific. At the other end of the spectrum, we can find no compelling morphological characters for separating specimens we consider to represent G. scabellana , yet DNA barcodes suggest there are at least two species concealed under our concept. Consequently, we must consider our circumscribed species as merely “estimates,” some of which lack distinct morphological boundaries. Nonetheless, we hope this contribution provides a framework for additional work on the genus when more specimens and DNA barcodes become available.

Key to males of Gibbalaria

1. Underside of hindwing without patch of gray to black secondary scales; uncus long with distinct junction at top of tegumen; socii not fused to base of uncus; costa of valva with a basal or subbasal process or region bearing slender spines......... 2

1’. Underside of hindwing with conspicuous patch of gray to black secondary scales; uncus broad basally (short or ill defined), without distinct junction at top of tegumen; socii fused to base of uncus; costa of valva without a basal process or region of slender spines........................................................................................ 3

2. Flange at lower base of cucullus broad, with inner patch of setae not exceeding basal width of flange......... occidentana

2’. Flange at lower base of cucullus narrow, with inner patch of setae exceeding basal width of flange.............. chiloanei

3. Sacculus with dense patch of spiniform setae (Spc 2) above “flange,” immediately below base of cucullus................ 4

3’. Sacculus with dense patch of spiniform setae (Spc 2) basal to “flange”................................... bagamoyo

4. Tegumen broadly rounded in dorso-posterior half....................................................... analcis

4’. Tegumen more narrowly rounded dorso-posteriorly.......................................................... 5

5. Phallus conspicuously elongate and attenuate in distal half............................................ longiphallus

5’. Phallus more-or-less truncate distally...................................................................... 6

6. Uncus greatly reduced....................................................................... mabalingwae

6’ Uncus short, tapering distally................................................................... scabellana

Figures

FIGURE 1. Maximum (ML) likelihood tree for species of Gibbalaria and out-groups.

FIGURE 2. Bayesian tree for species of Gibbalaria and out-groups.

FIGURES 3‒10. Adults of Gibbalaria. 3. G. divergana holotype female; 4. G. chiloanei holotype male; 5. G. occidentana paratype female; 6. G. occidentana holotype male; 7. G. occidentana paratype female; 8. G. longiphallus holotype male; 9. G. mabalingwae holotype male; 10. G. scabellana male, South Africa.

FIGURES 11‒18. Adults of Gibbalaria. 11. G. scabellana female, South Africa; 12. G. bagamoyo male, Tanzania; 13. G. bagamoyo female, Tanzania; 14. G. analcis male, Democratic Republic of the Congo; 15. G. analcis female, Democratic Republic of the Congo; 16. G. scabellana male underside, South Africa; 17. G. bagamoyo male underside, Kenya; 18. G. mabalingwae holotype male, underside.

FIGURES 19‒24. Male genitalia of Gibbalaria. 19. G. occidentana, USNM slide 145,608; 20. G. chiloanei, USNM slide 145,619 (HT); 21. G. chiloanei, USNM slide 145,615 (PT); 22. G. scabellana, USNM slide 144,616; 23. G. scabellana, USNM slide 145,603; 24. G. longiphallus, Bassi slide 6441(HT).

FIGURES 25‒29. Male genitalia of Gibbalaria. 25. G. mabalingwae, Razowski slide 311; 26. G. bagamoyo, USNM slide 144,518; 27. G. bagamoyo, USNM slide 145,796; 28. G. analcis, GS 6476 (HT); 29. G. analcis, USNM slide 145,604.

FIGURES 30‒35. Female genitalia of Gibbalaria. 30. G. divergana, USNM slide 145.609; 31. G. occidentana, USNM slide 145,620; 32. G. chiloanei, USNM slide 145,979; 33. G. scabellana, USNM slide 144,801; 34. G. scabellana, USNM slide 145,652; 35. G. bagamoyo, NHMO slide 4116.

FIGURES 36‒38. Gibbalaria and Cosmopoda. 36, Gibbalaria analcis, female genitalia, USNM slide 145,605. 37. Cosmopoda graziani, male holotype; 38. C. graziani, male genitalia, Razowski slide 6420.