Shimbania, Lehmann & Dalsgaard, 2023

Lehmann, Ingo & Dalsgaard, Thure, 2023, Revision of Saalmulleria Mabille, 1891 (Lepidoptera, Metarbelidae) from Madagascar with the description of three new genera and fifteen new species, Evolutionary Systematics 7 (1), pp. 133-182 : 133

publication ID

https://dx.doi.org/10.3897/evolsyst.7.85204

publication LSID

lsid:zoobank.org:pub:24DF15AD-F8A0-4086-AD8C-60AD39C8A4AA

persistent identifier

https://treatment.plazi.org/id/77DFB25C-196F-4927-8015-42577A843227

taxon LSID

lsid:zoobank.org:act:77DFB25C-196F-4927-8015-42577A843227

treatment provided by

Evolutionary Systematics by Pensoft

scientific name

Shimbania
status

gen. nov.

Shimbania gen. nov.

Type species of genus.

Shimbania baginerichardi sp. nov. is designated as the type species.

Diagnosis.

= Autapomorphies in Lehmann 2019b - The genus is defined by the following combination of characters (cf. Lehmann 2019b, 106-110): the thorn-like lower gnathal arm is 30-35% the size of valva, and is connected to the base of uncus by a long and narrow weakly sclerotized band that has 25-30% the width of the dorsal length of the thorn-like structure.

Differential diagnosis.

(= Synapomorphies in Lehmann 2019b) shared with Morondavania gen. nov. from Madagascar.

Forewing venation: R1+R2 originating from a long, well visible stalk (the stalk has the length of 25-60% of R3) in both sexes.

Male genitalia: Uncus narrow (60% or less than width of transtilla in ventral view), elongated with heavy appearance, strongly sclerotized, and with a more or less flat dorsal surface that is bent like a “C” in lateral view with a broadly rounded tip.

Lower part of gnathal arm represents a strongly sclerotized thorn with a broader base and an acuminate tip (15-35% the size of valva) and is connected in its upper part by a band to the base of uncus (the band has 30-50% the width of the thorn-like structure); the gnathal arms are connected by a narrow sclerotized band ventrally and end well above the costa of valva.

The transtilla (rarely present in Metarbelidae ) is weakly sclerotized, very broad, ca. 30-40% of basal width of valva.

Diagnostic character in females of Shimbania gen. nov.

A very large sclerotized base of the medium long posterior apophysis that is as large as ca. 40-50% of the papillae anales.

Diagnostic character in males of Shimbania gen. nov.

The phallus is among the largest in Metarbelidae, with 30-40% as broad as basal width of valva on ca. 2/3 of its length and 20-30% longer than dorsal edge of valva; the remaining 1/3 is very narrow and bent upwards distally.

Description.

Head (Figs 1a-d View Figure 1 , 2a-e View Figure 2 , 3a-f View Figure 3 ): Rough-scaled; long hair-like scales of olive-brown or greyish-olive or deep olive-buff on fronto-clypeus; a pair of pits absent in female (cf. S. kerstinhempae sp. nov.), but usually present or rudimentary in male (cf. S. tanaensis sp. nov., S. mbarikaensis sp. nov., S. krooni sp. nov.) on lower fronto-clypeus, a pair of small conical projections usually absent in males, but projections well visible in S. krooni sp. nov., rudimentary projections present in S. mbarikaensis sp. nov., sometimes present in females on lower fronto-clypeus at same position as in males; if present in females the projections are well developed, separated, but close together, small thorn-like in between two tiny slits or small oval holes behind labial palpi, holes or slits are sometimes absent in both sexes; labial palpi short or medium long, less than half of eye diameter, rarely longer (cf. S. puguensis sp. nov.), consisting of two segments; 2nd segment longest, elongated oval, up to 2.5-3.0 × longer than 1st (basal) segment; apical palpomere usually absent, sometimes present, shortest, 0.3 × length of basal segment in both sexes. Antennae in both sexes bipectinate, branches up 4.0 × longer than width of shaft in males, also long in females with branches up 2.5-3.5 × longer than width of shaft, branches are widely separated at base in both sexes with 1.5 × width of branch, rarely not widely separated in males, dorsal and lateral sides of branches not scaled, but with many setae ventrally and laterally, dorsal and lateral sides of flagellum scaled in both sexes brown, ivory-yellow or greyish-olive.

Thorax: Densely covered with hair-like scales of deep olive-buff or cream-olive on patagia, often these scales have a light grey or white tip, scales on patagia form often a collar ring, scales on tegulae dark chestnut or sepia with a vinaceous or light lilac glint in males, a glint is usually absent in females; long scale crest on metathorax, usually cream and dark chestnut at centre. Fore and mid legs cream-olive with long dense hair-like structures. Epiphyses present in both sexes, long, up to 2.0 mm in males, up to 2.5 mm in females, broad and flat, sometimes tube-like in females. Hindlegs usually deep olive-buff, on lower part of tarsus dark chestnut or light brown dorsally in males, but often only deep olive-buff in females, with two pairs of tibial spurs in both sexes (only S. nigeriaensis sp. nov. has one pair of tibial spurs), lower pair broader and shorter, up to 1.9 mm long, upper pair more narrow, up to 2.1 mm long, all spurs with thorn-like tip in both sexes. Wingspan is between 41.0 mm up to 54.0 mm with generally smaller species to the South of the Limpopo River (roughly to the South of Zimbabwe) with highest wingspan 48.0 mm, very often 44.0 mm or less. Forewing broad in both sexes, upperside usually with a light golden glint on an olive-grey or olive-cream ground-colour, sometimes inner half of forewing olive-brown, scale pattern is weak, usually a broad “Y” -shaped or “V” -shaped design occurs from near apex and costa or from R5 to the middle or near end of CuA1 or CuA2, the latter is sometimes narrowly sepia in both sexes, usually several narrow olive lines are present from costa to dorsum, often interrupted by sepia veins in both sexes, termen without lunules, a dark chestnut or sepia patch is present below base of 1A+2A, sometimes faded. Hindwing is ivory-yellow or light olive-cream with a glint, sometimes with a light brown patch at end of discal cell, usually with light brown veins and several weak light brown or deep olive-buff patches at inner margin that sometimes form a weak reticulated pattern. Forewing venation similar in both sexes (Fig. 6a, b View Figure 6 ) with 1A+2A forked or only slightly forked at base; CuP absent; CuA2 originating from near hind margin of posterior cell in both sexes; CuA1, M3 and M2 separate and originating from apical angle of posterior cell in both sexes; M1 originating from distal margin of median cell in both sexes; areole always absent in both sexes; R1+R2 originating from a long stalk (the stalk has the length of 40-60% of R3) and initiating from anterior margin of median cell in both sexes; R3+R4+R5 are long stalked and originating from anterior angle of median cell; Sc more or less parallel to R1. Hindwing venation similar in both sexes with 3A present, 1A+2A present usually as a sclerotized fold, rarely with a small fork at base, CuP usually absent and represented by a not sclerotized fold, if the fold is present, it is weak; CuA2 originating from hind margin of posterior cell; CuA1, M3 and M2 originating from apical angle of posterior cell, separated; M1 and Rs originating from apical angle of anterior cell, broadly separated in both sexes; without a bar from Rs to Sc+R1 in both sexes, except S. kerstinhempae sp. nov. where a short bar is present near the base of both veins (Fig. 6a View Figure 6 ), with a small vein in discocellular cell on both fore- and hindwing, very rarely forked in forewing like in S. baginerichardi sp. nov. Fringe scales dark cream or olive, short in both sexes, up to 1.2 mm on forewing and hindwing. Retinaculum and frenulum are absent in both sexes.

Abdomen: With dense hair-like scales of greyish-olive or olive-brown and abdominal tuft, usually short, not longer than one-third of abdomen. Male genitalia (Figs 7e View Figure 7 , 8a-d View Figure 8 , 9a-d View Figure 9 , 10A-C View Figure 10 , 12a View Figure 12 ), with tegumen and vinculum fused, forming a firm narrow ring, with tegumen ca. 3.0-3.5 × broader than vinculum, the latter forms a narrow (cf. S. tanaensis sp. nov., S. krooni sp. nov.) or broad ring ventrally (cf. S. budaensis sp. nov., S. wanjakinuthiaae sp. nov.). Uncus with heavy appearance, narrow elongated, well sclerotized, up to 40-90% of length of whole gnathos, flat dorsally, sometimes with a narrow graben-like surface ventrally, never bifurcated at tip, with few tiny setae ventrally and occasionally dorsally, tip rounded. Basal edge of uncus well developed, not bent at center. Gnathos has gnathos arms that are large, one arm 40-60% the size of valva: upper part of the gnathos arm is a long or short, weakly sclerotized band, as long as 25-50% of basal width of valva, that is attached to the basal part of uncus, the lower part of the gnathal arm is strongly sclerotized, of triangular or slightly rectangular shape (cf. S. budaensis sp. nov.) with a pronounced thorn-like structure and with its base in length up to 70% of the basal width of valva, sometimes smaller thorns are present along the dorsal edge or the dorsal edge is serrate or nearly straight (cf. S. pwaniensis sp. nov.), however, folds are always absent; the longest thorn might be hollow while the remaining part of the triangular-shaped or slightly rectangular-shaped gnathos is not hollow; the gnathal arms are connected ventrally by a sclerotized band that is as broad as 15-50% of the transtilla. The Gnathos is short and ends always well above the costa of valva. The valva is large, short and broad, or elongated and broad, almost rectangular, sometimes triangular, tip broadly or narrowly rounded (cf. S. baginerichardi sp. nov., S. krooni sp. nov.) or broadly pointed (cf. S. puguensis sp. nov.); sacculus narrow (cf. S. kaguruensis sp. nov.) or broad (cf. S. budaensis sp. nov.), weakly sclerotized, 30-60% of length of ventral edge of valva, costal margin only weakly sclerotized at base of valva; soft setae occur on inner side of valva, but no other structures are present. Saccus always absent. The vinculum is very narrow (cf. S. krooni sp. nov.) or very broad (cf. S. budaensis sp. nov.), juxta well developed, with two broadly oval or ear-shaped or broadly rectangular lobes and usually a deep V-shaped emargination in between lobes, the tips of lobes are broadly rounded (cf. Shimbania kaguruensis sp. nov.) or pointed (cf. Shimbania durbanica ) or the dorsal edge of juxta is straight (cf. S. krooni sp. nov.). Phallus simple, tube-like, but very large, as broad as 35-50% of basal width of valva and up to 20-50% longer than costal width of valva, straight, usually strongly bent upwards at tip distally, vesica without cornuti. Female postabdominal structure and genitalia (Figs 7c View Figure 7 , 10C View Figure 10 ) with papillae anales medium broad to narrow; dorsal part obliquely 8-shaped or elliptic in posterior view, covered with short and long setae. Segment 8 represents a medium broad rectangular sclerotized band, usually setose along its posterior margin with long setae, sometimes there is an oblique single row of medium long setae on the whole segment 8 (cf. S. kerstinhempae sp. nov.), with a very narrow band attached ventrally extending to the base of anterior apophysis; anterior apophysis up to 2.0 × as long as segment 8 dorsally; posterior apophysis up to 50% the length of anterior apophysis and with a large sclerotized base up to 50% the size of the papillae anales in lateral view (in all females); ductus bursae thinly membranous, not sclerotized at base or thinly sclerotized at base (cf. S. nigeriaensis sp. nov.), narrow, very long, namely longer than the length of the very large corpus bursae or 3.0 × as long as the dorsal width of segment 8, and among the longest in Metarbelidae (cf. S. durbanica ); corpus bursae thinly membranous and without any structures or processes, elongated oval-shaped or broadly pear-shaped, very large, up to 2 × as large as the broad segment 8 in lateral view.

Species richness.

Currently, 13 species are included in this new genus of which 11 species are described as new to science.

Distribution.

Species of Shimbania occur in southern and eastern Africa with a remarkable proximity to the Indian Ocean coast, with one (relict?) record from an area close to the Atlantic Ocean in coastal Nigeria (Lower Guinea, Central Africa) (cf. distribution map in Lehmann 2019b, fig. 51). The presented species are most probably restricted to various drier as well as wetter types of coastal lowland forest and/or woodlands, including riverine forests, as well as (rarely?) submontane and montane forests, e.g. on the Eastern Arc Mountains of Tanzania. Their distribution range extends within lowland areas of the "Tongaland-Pondoland regional mosaic" sensu White (1983) from the "Transkei Coastal Belt" (Republic of South Africa) northwards via the "KwaZulu-Natal Coastal Belt" and "Maputaland Coastal Belt" (within the Indian Ocean Coastal Belt) sensu Mucina et al. (2006b) inland to montane areas that belong to the "Zambezian regional centre of endemism" and are located close to the borderline with the "Kalahari-Highveld regional transition zone" sensu White (1983) and within the "Central Bushveld Bioregion" sensu Rutherford et al. (2006), e.g. Pretoria and Johannesburg located ca. 540 km inland from the Indian Ocean coastline. Along the latter coastline species extend northwards into the "Zanzibar-Inhambane regional mosaic" sensu White (1983), most probably through Mozambique, to eastern Tanzania and eastern Kenya. In eastern Tanzania, species of Shimbania occur ca. 300 km inland, e.g. in the Mahenge - Mbarika mountain chain (also known as Mbaraka Mountains cf. Kielland 1990), that is part of the "southern Eastern Arc Mountains" (cf. Lovett 1998) and of the "Afromontane archipelago-like regional centre of endemism" sensu White (1983). Via the transition zones of the Eastern Arc Mountains they extend probably into the Zambezian regional centre of endemism as well as Zanzibar-Inhambane regional mosaic. Further to the north, species occur on medium elevations at Usa River (1225 m, near Mount Meru) and within the transition zone of the Afromontane archipelago-like regional centre of endemism and the "Somalia-Masai regional centre of endemism" sensu White (1983). Within the Somalia-Masai regional centre of endemism species of Shimbania extend northwards into eastern Kenya, e.g. via Kibwezi (altitude 919 m, ca. 250 km inland from the Indian Ocean) to the Tana River. The Tana River Primate National Reserve (171 km2, altitude ca. 40 m, 80 km inland from the Indian Ocean) is located within the borderline of the Somalia-Masai regional centre of endemism and Zanzibar-Inhambane regional mosaic and is currently the most northeastern distribution limit and Port St. Johns in the Tongaland-Pondoland regional mosaic the most southeastern limit; an unknown coastal area in Nigeria is currently the most northwestern limit and is located in the "Guineo-Congolian regional centre of endemism" sensu White (1983); areas around Pretoria and within the Zambezian regional centre of endemism represent the southwestern limit. Within this vast area, species of Shimbania have a scattered, often isolated, small distribution that most probably is less than 50.000 km2 per species (cf. S. baginerichardi sp. nov. and S. tanaensis sp. nov.).

Species of Shimbania occur from an altitude of 1 m (in coastal Nigeria) and 19 m (Shimo la Tewa, Kenya) up to 1.900 m (Ukaguru Mountains, Tanzania) in a range of climate types, e.g. warm temperate climate, subtropical humid climate and tropical wet and dry climate. The average annual rainfall in these habitats varies from at least 559 mm in the Central Bushveld Bioregion ( Rutherford et al. 2006), between 300-1000 mm along the Lower and Upper Tana River ( Andrews et al. 1975; Hughes 1990), 1073 mm at Mombasa / Shimo la Tewa, 1236 mm at Kisarawe Forest / Pugu Hills (Tanzania; Howell 1981), 1151-1263 mm in the Shimba Hills ( Schultka 1974; Jätzold and Schmidt 1983) and 1300-1500 mm in the Mahenge-Mbarika mountain chain (CELP 2007) with the highest average rainfall in coastal Nigeria with 2000-3000 mm, locally more than 3000 mm.

The single record of a species of Shimbania from an unknown locality in coastal Nigeria is unusual, but if the two labels on this female are correct, species of Shimbania are also likely to occur in relict forests or woodlands in lowland, submontane and/or montane areas of Central Africa and West Africa.

Biological traits.

The biology of all species of Shimbania is unknown at present. However, lowland tropical Metarbelidae species, as various species of Shimbania , are strongly associated to woody legumes, particularly with legume-dominated forests, woodlands or other legume-dominated woody vegetation types ( Lehmann 2008, 2019b, Pp. 342-349) with few exceptions ( Jenoh et al. 2016, 2021).

Etymology.

The genus is named after Kenya’s premier area for plant diversity (cf. Luke 2005), namely for the lowland area of the "Shimba Hills" (for more information on the etymology of the word “Shimba” see Appendix 1) in the southwest of Mombasa. The areas of the Shimba Hills and Mombasa represent two type localities for two new species of this genus.

The gender of the new genus is feminine.

Key to the species of Shimbania

The key is based primarily on characters of the genitalia; hence, it cannot serve as a field identification key. For the majority of species, only a few specimens are available, so identifications obtained from this key should be cross-checked carefully with the description, distribution, and figures presented in this paper. The males of Shimbania kerstinhempae sp. nov. and S. nigeriaensis sp. nov. are unknown.

1 Male 2
- Female 8
2(1) Valvae short, dorsal edge 1.3 × or 1.4 × length of uncus; valvae rectangular, distally broadly rounded 3
- Valvae long, dorsal edge at least 2.0 × length of uncus 5
3(2) Viculum narrow 4
- Vinculum broad, ventrally at least 2.0 × width of upper half of vinculum, broadest vinculum ventrally in genus, namely 55% as broad as basal width of valva S. wanjakinuthiaae sp. nov.
4(3) Vinculum narrow, ventrally 1.2 × width of upper half of vinculum, valvae with ventral edge not suddenly bent inwards S. baginerichardi sp. nov.
- Vinculum narrow, uncus in fresh preparation with well visible thickening ventrally S. wichgrafi
5(2) Valvae triangular, distally pointed 6
- Valvae rectangular, distally broadly rectangular 7
6(5) Antennae short, only 0.30 length of forewing S. kaguruensis sp. nov.
- Not as above, uncus very long with 90% of vertical length of gnathos S. puguensis sp. nov.
- Not as above, valva with very long dorsal edge of 2.4 × length of uncus, short uncus with 60% of vertical length of gnathos S. krooni sp. nov.
7(5) Large gnathal arms, one arm at least 50% the size of valva, valvae suddenly bent inwards ventrally S. tanaensis sp. nov.
- Not as above, vinculum with wavy shape on entire length S. pwaniensis sp. nov.
- Not as above, broadest tegumen in genus, namely broader than length of upper band-like structure on gnathos S. durbanica
- Not as above, vinculum very broad ventrally, 2.2 × width of upper half of vinculum and 45% as broad as basal width of valva S. budaensis sp. nov.
- Not as above, tegumen narrow with only 30% of basal width of valva, band that connects gnathal arms ventrally only 20% width of transtilla, widely bifurcated in the middle, ventral edge of valva oblique S. mbarikaensis sp. nov.
8(1) One pair of tibial spurs present on hindleg, dorsal gap on segment 8 present S. nigeriaensis sp. nov.
- Two pairs of tibial spurs present on hindleg, dorsal gap absent 9
9(8) Anterior apophyses almost equal in length to dorsal length of segment 8; base of posterior apophyses large, 40% size of papillae anales S. kerstinhempae sp. nov.
- Anterior apophyses at least 2.0 × longer than dorsal length of segment 8; base of posterior apophyses very large, 50% size of papillae anales, ductus bursae very long with 3 ×length of segment 8 dorsally S. durbanica

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Lepidoptera

Family

Metarbelidae