Iolaus (Iolaphilus) francisi, Gardiner, 2025

Gardiner, Alan John, 2025, A new Iolaus species (Lycaenidae: Theclinae) from the highlands of central Angola, Zootaxa 5660 (1), pp. 67-79 : 69-75

Iolaus (Iolaphilus) francisi sp. nov. Gardiner

Figs: 1 A–H

Common name: Francis’s gorgeous sapphire

Holotype: ♂ Mount Namba , Cuanza Sul, Angola, lat. -11.83 lon. 14.77 2650 m asl; 13.v.2023; A.J. Gardiner, S. Ndarama, J. Francis leg. Deposited in British Museum of Natural History, London.

Paratypes: 1♂ details as per Holotype but 16.vi.2023: 4♀♀ details as per Holotype, but two 6.xi.2022, one 30.vi.2023, one 7.x.2024 A.J. Gardiner leg: 1♂ and 3 ♀ Paratypes deposited in Gardiner Collection , South Africa, 1♀ Paratype in British Museum of Natural History , London .

Description of male. The description although based on the Holotype does include variation within the type specimens. Holotype ( Figs 1 B & D ). Wingspan: ♂ 32.3 mm, forewing length: 17 mm, Paratype 30 mm & 15.6 mm respectively. Antenna-wing ratio 0.49 & Paratype 0.52. Head, white with black, the two colours forming distinct bands or patches, a white band next to eyes running from just below antenna to base of palps, small section of black between this white and base of antenna, white band then runs up far side of eye stopping just before antenna which is black until antenna, a few white scales present at base of antenna, area between white stripes in centre of head black except between antennae which is white ( Fig. 1G ). Antennae black to dark brown with some white scaling ventrally on each segment, some scales also reflect blue, ventral surface of club brown lightest at tip and gradually darkening down the length of the antenna, apiculus blunt, rounded at end. Labial palpi: first segment (prementum) white with some black scales, second, ventrally white, black dorsally, towards base white encroaching the sides, apical segment mostly black, some white near base ventrally but becoming black.

Thorax. Above, black scattered with a few blue scales, numerous large white-black scales giving a grey appearance, covered with long light white-blue-grey hairs especially anteriorly where they are shorter than posteriorly, below, black becoming white centrally with numerous long white hairs centrally.

Legs: femora, outer aspect white, inner white with black scales, numerous long white hairs along lower edge, tibia outer aspect white, inner white, tarsi white with black patches on inner surface of each tarsal segment.

Abdomen. Above, black-grey scales with a bronze sheen towards their base, scattered with long light-coloured hair, becoming white below, especially basal half, segments before genital opening with more brown scales, a central brown-/black stripe, abdomen scattered with long light hair.

Wings. Upper side a shiny blue with black, the shade of blue varies depending on angle and type of light ( Figs 1B & C ). As in other Iolaus the blue areas are blue scales overlaying black scales. Forewing: approximately half blue rest black, the blue radiating out from base, along the inner margin, most of 1b blue but stopping at proximal border, most of 2 blue but blue extending further into proximal area in centre of space before receding sharply to half way along vein 2, just under half of space 3 blue, again with blue pointing outward in centre and then receding to about ¼ of the way along vein 3, just under a third of space 4 blue, similar design as in space 3, blue only in first quarter of space 5 again with similar pattern to proceeding space, cell blue, blue for approximately half the length of space 12, forming a narrow band of blue but adjacent to the blue of the cell, this patterning gives the blue a jagged appearance along its outer edge. Cilia: black with lower lighter scales extending beyond dark scales. Hindwing: mostly shiny blue with some black and grey, spaces 1a&b (anal fold) grey with scales having some light blue reflectance, border ocelli O, in anal lobe, forming an eyespot inner half red with a few blue scales and outer half black, oU 21 b with white scales, long white marginal hairs on 1b, and long grey hairs in spaces 1b and 2 densest in 1b especially along vein, spaces 2-6 with blue, Op2 present as a mark and joins the space 1b grey, Op3 smaller and present as a black spot, Op3-Op5 still visible but progressively forming part of Od (marginal border), hence the marginal border progressively increasing from space 4 and a noticeable increase in space 6, the black extending along the top margin of blue in 6 and expanding again as approaching the cell, space 7 black becoming lighter towards base. Posterior edge, proximal and distal area of cell with blue, the cell, base of 6 and proximal part of 7 taken up with a large circular sex brand ( Fig. 1H ). The centre of the brand a light beige which is encircled first by black then light grey scales, with a purplish reflection, and finally another black band, end of 1b with a long tail and a shorter tail at end of 2, the slight indication of a tail at end of 3. Cilia: white in 1b and along edge of tails, from 2–7 black with lighter scales extending beyond the black scales, from space 7 cilia white.

Underside a silver white. Forewing: Marginal border Od1b-Od7 a very faint brown. Proximal border, orange starting in upper half of Od1b and ending in Od6, interrupted at each vein, and progressively becoming lighter until very faint at Od6. The Median band M 1, very faint in upper-half of 1b but then bold from M 12 -M 19 brown and more clearly visible than Proximal border. Discal Mark, D, across end of cell brown-grey clearly visible. A tight bunch of long black hair pencils attached in the mid area of the inner margin, hairs reaching from inner margin to about ¾ of the way into 1b. Cilia: along inner margin consisting of long grey-brown hairs and on outer margin as white scales. Underside hindwing: Marginal border, from Od1-Od6, petering out as it enters 6, darker in Od1b-Od2 and then gradually becoming lighter, border ocelli O, in anal lobe, forming an eyespot outer half black, inner half red, with a few blue scales, and red edged due to some orange scales, O1b present as a patch of black and white scales, O5 & O6 very faint (a indistinct dark patch), O2 forming a dark spot edged by red/orange and dislodged so joins the Proximal border. Proximal border starting at 1b and joining the border ocelli, and ending in space 7, orange in colour, thickest near start and again in 3, where it is joined by the border ocelli, the line has a gap in 2 and dislodged basad in 7. Median band from M 11 a-M 17, the line in 1a and 1b is almost black and then becomes lighter (brown), in 1a the line is parallel to the border but at vein 1b it turns sharply towards the base and then takes another sharp turn towards the margin were it then makes a more gentle but noticeable curve inwards, at vein 2 it again forms a small indent before continuing to vein 3 were it again turns outward briefly before continuing to vein 4, this gives the line a dislodged appearance in spaces 1b-2, then more or less straight in 3-5, slightly dislodged in 6 and disjunct in 7. A brown discal mark present across end of cell. Cilia: along edge of anal fold with long white hairs, from anal lobe to space 6 as white scales, these become hair like from 7 and longest in space 8.

Male genitalia ( Fig. 2 ). Aedeagus ( Figs 2 A–C ) basal area were vesica enters sheath, laterally bulbous and broader than remainder of aedeagus, narrowing before annulus then slender widening at apex were vesica leaves sheath. There are two cornuti at the apex, one stout and the other slender, the position of the slender one depends how much the vesica is extended, the stouter cornuti is also attached to the vesica but can give the appearance of being part of the sheath depending on how viewed, it is unclear if there is some softer tissue attachment to the sheath.

Valves asymmetric and rather complex ( Fig. 2A ), if opened ( Figs 2 D–F ), broad at base and first 2/3rds a slightly dislodged pear shape then bending and producing process’s being at a 90º plane to the broad base.

Uncus forming an unusual structure ( Fig. 2A ), the v between the lobes forming a slight protuberance, the lobes consisting or producing a number of lobes, the largest forming a structure reminiscent in appearance of a bat ear ( Figs 2A, G–I ), there are then three protuberances, almost spine like, the anterior one being longest ( Figs 2A, G–I ), between this and the posterior large structure is another protuberance ( Figs 2A, G–I ), each being formed from a u shaped valley of the uncus, the third and smallest but sharpest is on the lateral edge of the uncus ( Figs 2A , G-I), subunci long, slightly twisted and with a sharp curved tip ( Figs 2A, G–I ).

Vinculum narrows in the middle and bends outward ( Fig. 2A ). There is a large hood shaped curved structure, the pseudotergum of Stempffer & Bennett (1958), which appears to protect the uncus rather like a shield ( Figs 2A, G–I ). This structure may possibly also be derived from abdominal segment 9 and at the ventral side mimics the vinculum.

Description of female ( Figs 1 E & F ). Wingspan: ♀ 36.2 mm, mean 32.1 mm (n=4). Forewing length: 18.1 mm, mean 17.35 mm (n=4). Antenna-wing ratio 0.48, mean 0.45 (n=3). As in Holotype male but with the following differences. Thorax. Below, black but covered with white scales and with numerous long white hairs centrally.

Wings. Forewing shape, outer margin more curved inward than male, giving the butterfly a bulkier appearance than the male. Upper side a dull blue with black. All blue areas are blue scales overlaying black scales. Forewing: slightly more black than blue, the blue radiating out from base, along the inner margin, most of 1b blue but stopping at proximal border, proximal border wider than male in 1, under a third of space 4 blue, similar design as in space 3, blue only in first quarter of space 5 again with similar pattern to proceeding space, most of cell blue, just outer distal part with black, end of cell with black of vein protruding into the cell blue, the blue of this area having some white scales giving the blue a hint of white, blue for approximately half the length of space 12, forming a narrow band of blue but adjacent to the blue of the cell, the patterning of the blue gives the blue a jagged appearance along its outer edge. Hindwing: mostly dull blue with some black and grey, spaces more prominent than male, long grey hairs in spaces 1b and 2 with them densest in 1b but also present across wing to cell, becoming sparser and restricted more towards base, spaces 2–6 with blue, Op present as large spots in spaces 2–4 otherwise forms part of marginal black Od (marginal border) black, Space 7 black, 8 & 9 black but with large greyish area centrally. Cell mostly blue with a small black mark at end of cell at beginning of space 6.

Underside a silver white. Forewing: Marginal border Od1b-Od7 a faint orange/brown. Proximal border, orange/ brown starting as a faint diagonal line in 1a then a slightly curved line from Od1b which ends in Od7, the mark in Od7 being slightly displaced towards base, lines in between veins slightly curved, line most orange from Od1b-3. The Median band M 1, as in Proximal border starts with a very faint angled line in 1a then noticeable from M 11 b- M 19 more brown in colour than Proximal border. M 11 b and M 12 in line with one another but M 13 slightly dislodged towards margin but then forms an almost straight line M 13 -M 19. Discal Mark, D, across end of cell brown/grey clearly visible. The white between Od and M1 appears more brilliant white than on either side. Outer portion of veins darkened a brown/orange. Cilia: along inner margin consisting of long grey/brown hairs while on outer margin white scales, which become reduced and black towards apex. Costa faintly brown. Underside hindwing: Marginal border, in 1 and 1a black with some orange, black from Od1b-Od3, at Od3 it begins to have some brown which takes over from the black and faint in Od6, border ocelli O, in anal lobe, forming an eyespot outer half black, inner half red, with a few blue scales, and red edged by some orange scales, O1b present as a patch of black scales overlayed with white scales, O4-O6 very faint (as indistinct dark marks), O2 forming a dark spot edged by red/orange and dislodged so joins the Proximal border. Proximal border starting at 1b joining the border ocelli, ending in space 7, distinctly orange in colour, mark in 7 slightly dislodged basad. Median band from M 11 a-M 17, the line in 1a and 1b is almost black and then becomes lighter (brown), in 1a the line is parallel to the border, at vein 1b it is noticeably dislodged basad then runs outward but in the middle of 1b forms a sharp angle, almost 90 degrees, and continues to vein 2 were it again turns outward briefly before continuing to vein 3, this pattern is repeated in space 3, this gives the line a dislodged appearance in spaces 1b-3, the line is then straight and only very slightly bent in 7. A brown discal mark present across end of cell. Cilia: along edge of anal fold with long white hairs, from anal lobe to space 6 with white scales distally darkened, from 7 white and more hair like.

Female genitalia ( Figs 3 A & B ). The ovipositor lobes appear quite similar amongst Iolaus species in contrast the external genitalia can show differences amongst species ( Heath 1985). In the present species the genital plate or sterigma forms a distinct structure for receiving the male genitalia ( Figs 3A & B ). The sterigma is convex, however the lamella postvaginalis is broadly indented, ventrally, to form a significant gap between it and the lamella antevaginalis, this gap forms the ostium and leads into the antrum, the antrum is initially rectangular in shape and flattened but reduces to form a straight tube ( Fig. 3B ), it then narrows further to form the ductus bursae. The posterior edge of the lamella antevaginalis is wavy but in the centre is indented to form two short blunt, rounded, horns, the central part of the lamella antevaginalis forming a hood over the ostium. The ductus bursae form a short cervix before the corpus bursae, the corpus bursae is oval in shape with a small cone shaped appendix bursae at the end ( Fig. 3B ). The surface of the corpus bursae appears to be covered with small granulations.

Habitat and ethology. To date, this species has only been found at high-altitude above 1500 m in the central highlands of Cuanza Sul Province. It appears to be associated with high altitude forest. The male was seen to fly on the side of a forest tree in the sun. It would stop and spend long periods sunning itself but not on the crown of the tree. It would take territorial flights and then alight again but not necessarily at the same spot. Females were observed ovipositing at various heights in the forest and larvae were found on a species of Phragmenthera ( Loranthaceae ) in the forest and even some distance from the forest on isolated Phragmenthera -infested trees.

Flight period. This species is likely to fly throughout the year as various stages of the life cycle were found in both October and May. However, it is likely that there are peak periods of adult activity.

Life history. Eggs were found on the leaves and stems of the foodplant, particularly at the base of buds ( Fig. 4A ). Larvae were found feeding on the young shoots ( Figs 4B, C ), especially the earlier instars and leaves (Figs D–F), the larvae, particularly the final instars, may be green ( Fig. 4 E ) or a brown in colour ( Fig. 4 F ). The larvae have the same general appearance as members of Argiolaus and Iolaphilus . This body form may be conserved due to its being so well adapted as camouflage with the foodplant. The pupa ( Figs 4 G–I ) was not found in the wild but is also typical of these groups, and in general colour can be green (Fig. G) or green with grey speckling (Figs H, I).

Etymology. This species is named after the Francis family, who have encouraged the conservation of our environment, in particular Jonathan who has also added much to our knowledge of south-central African butterflies and obtained the first larva of this species.

Distribution. According to present knowledge, the species is restricted to the montane forests of the central Angolan highlands around the Alto Hama area.

Diagnostic Features. This species is similar in size and appearance to the following large Iolaus species: I. cottrelli , I. paneperata , I. dianae , I. kayonza , I. kupe , I. pamae , and I. parasilanus Rebel 1914 , (and possibly I. bergeri Stempffer 1953 , but the only known specimen of this species is in poor condition). All these species, including the present one, have two distinctive submarginal lines on the verso of the hind and fore wings. The present species, however, can be distinguished by the presence of a distinct line at the end of the cell on the verso of both the fore and hindwing. If, in the other species, there is a line at the end of the cell, it is only on the forewing, faint and nothing on the hindwing.

Figures

FIGURE 1. Iolaus francisi sp. nov. A, terminology used to describe the pattern elements of the wings; B, upperside Holotype ♂; C, upperside Paratype ♂ illustrating colour variation with angled sunlight; D, underside Holotype ♂; E, upperside Paratype ♀; F, underside Paratype ♀; G, head showing colouration around eye and palps; H, ♂ hindwing upperside sex patch. Scale bar: for B, D, E and F = 7.5 mm; for G and H = 0.925 mm.

FIGURE 2. Iolaus francisi sp. nov. A, complete external male genitalia after dissection from abdomen but with parts intact; B, aedeagus lateral view and C, ventral view; D, valves ventral view, E, dorsal view, F, lateral view; G, uncus and pseudotergum ventral view, H, dorsal view and I, lateral view. Scale bar = 0.925 mm.

FIGURE 3. Iolaus francisi sp. nov. A, female external genital in situ; B, female external and internal genitalia after dissection from abdomen. Scale bar = 0.925 mm.

FIGURE 4. Iolaus francisi sp. nov. life stages. A, egg, arrow; B and C, early instar larvae, arrows; D–F, final instar larvae; G and H latero-dorsal view and I, dorsal view of pupa.