Spialia spio Linnaeus, 1764

Cock, Matthew J. W., 2016, Observations on the biology of Afrotropical Hesperiidae (Lepidoptera) with particular reference to Kenya. Part 10. Pyrginae, Carcharodini, Zootaxa 4173 (4), pp. 301-350 : 308-313

Spialia spio Linnaeus, 1764

This is the first of three species which comprise the spio group of De Jong (1978); the others are S. diomus and S. ferax . Originally described from the Cape of Good Hope ( Linnaeus 1764), S. spio species is found throughout sub- Saharan Africa and in Yemen ( De Jong 1978). It is recorded more or less throughout Kenya, except the undercollected dry north-east. It is found in a variety of habitats from dry scrub and semi-desert areas to the wet rain forests of the West. De Jong (1978) suggests that in East Africa it is an adaptable species which prefers fringes of thick scrub and sometimes forest paths. Although widespread, it is seldom abundant, being found usually in small numbers. Van Someren (1939), however, reports it the most common of the genus in the grasslands and along forest margins of the Chyulu Hills.

I have found the adults, particularly the females quite variable: the white spot at the base of the UPF costa may be very weak or missing, the UPH submarginal spots in spaces 4 and 5 are not always fused, and the UNH pale markings vary. For example, a female reared from Pavonia urens near Timboroa (MJWC 88/100) was initially identified as S. mafa higginsi Evans (Figure 6.3–4), but comparison of the genitalia with De Jong’s (1978) illustrations clarified its identity. Fortunately this food plant record did not get into the literature.

Adult behaviour. The adults occasionally feed at animal (herbivore) dung, and I have noted specimens at donkey dung (Magadi Road, vi.1990). They come readily to flowers as for example in Figure 6.1. Migdoll (1988) refers to adults returning frequently to a chosen perch, presumably territorial behaviour by males. Cooper (1973) states that at least in Zimbabwe it is fond of flowers and damp mud, and also frequents peaks—a habit I have not noted for any Spialia spp.

Food plants. This species has been recorded to feed on a variety of Malvaceae . With records from East, South and West Africa, it is not always clear whether authors are providing new observations or citing older records not necessarily from the geographic area which they treat. I have attempted to disentangle these in Table 3. At the moment, the many records from Hermannia spp. seem to relate only to South African observations, whereas most other food plant genera seem to be widely used.

Species Location Reference

Althaea sp. Uganda Le Pelley 1959, Sevastopulo 1975, Larsen 2005

Hermannia spp. [South Africa] Kielland 1990, Larsen 1991, Heath et al. 2002, Larsen 2005

Hermannia coccocarpa South Africa Dickson & Kroon 1978, Pringle et al. 1994, Henning et al. 1997,

Woodhall 2005

Hermannia comosa (= camosa) South Africa Murray 1959, Dickson & Kroon 1978, Pringle et al. 1994, Henning et

al. 1997, Woodhall 2005

Hermannia cuneifolia (= South Africa Murray 1959, Dickson & Kroon 1978, Pringle et al. 1994, Henning et

pallens,= pallius, = pollens) al. 1997, Woodhall 2005

Hermannia diffusa (= pilosula) South Africa Murray 1959, Dickson & Kroon 1978, Pringle et al. 1994, Henning et

al. 1997, Woodhall 2005

Hermannia incana (= candicans, South Africa Murray 1959, Dickson & Kroon 1978, Pringle et al. 1994, Henning et

= candicamus) al. 1997, Woodhall 2005

Hibiscus sp(p). Kenya Le Pelley 1959, Sevastopulo 1975, Larsen 1991 [Afrotropical] Larsen 2005

Hibiscus aethiopicus Malawi, South Gifford 1965, Dickson & Kroon 1978, Kielland 1990, Pringle et al.

Africa 1994, Henning et al. 1997, Heath et al. 2002, Woodhall 2005

Hibiscus asper Côte d’Ivoire Vuattoux 1999

Hibiscus cannabinus Uganda Le Pelley 1959

Hibiscus diversifolius Uganda Le Pelley 1959

Hibiscus fuscus (?) (= H. East Africa Van Someren 1974

gossyphina )

Hibiscus pusillus (= gossypinus ) South Africa Platt 1921, Dickson & Kroon 1978, Pringle et al. 1994, Henning et al.

1997, Heath et al. 2002, Woodhall 2005

Hibiscus rostellatus Côte d’Ivoire Vuattoux 1999

Malva arborea (= Lavatera South Africa Dickson & Kroon 1978, Pringle et al. 1994, Henning et al. 1997,

arborea ) Woodhall 2005

Malva sp(p). (= Lavatera sp(p).) [South Africa] Larsen 1991, 2005

Malvaceae unidentified DR Congo Fontaine 1988

Pavonia sp(p). East Africa Sevastopulo 1975, Larsen 1991

[Afrotropical] Larsen 2005

Pavonia burchellii (= South Africa Platt 1921, Murray 1959, Dickson & Kroon 1978, Kielland 1990,

macrophylla, = patens) Pringle et al. 1994, Henning et al. 1997, Heath et al. 2002, Woodhall

2005

Pavonia columella South Africa Murray 1959, Dickson & Kroon 1978, Kielland 1990, Pringle et al.

1994, Henning et al. 1997, Heath et al. 2002, Woodhall 2005

Sida sp(p). Kenya Van Someren 1939, Sevastopulo 1975, Kielland 1990, Larsen 1991

South Africa Henning et al. 1997, Woodhall 2005 [Afrotropical] Larsen 2005

S. cordifolia East Africa Van Someren 1974

S. ovata (?) (= S. grewioides ) East Africa Van Someren 1974

S. schimperiana East Africa Van Someren 1974

S. rhombifolia Uganda Sevastopulo (unpublished)

......continued on the next page Species Location Reference

S. tenuicarpa (= S. cuneifolia ) East Africa Van Someren 1974

Triumfetta sp(p). South Africa Dickson & Kroon 1978, Larsen 1991, Pringle et al. 1994, Henning et

al. 1997, Woodhall 2005 [Afrotropical] Larsen 2005

Triumfetta rhomboidea Côte d’Ivoire Vuattoux 1999

Urena lobata 1 Côte d’Ivoire Vuattoux 1999, Larsen 2005

Wissadula amplissima Côte d’Ivoire Vuattoux 1999, Larsen 2005

1 A pantropical weed probably of Asian origin (Austin 1999).

Two names in Van Someren (1974) need discussion. He lists S. schimperiana , S. cordifolia , S. ovata (?) (= S. grewioides ), S. tenuicarpa (= S. cuneifolia ) and Hibiscus fuscus (?) (= H. gossyphina ) for East Africa. I am treating his record of S. cuneifolia as S. tenuicarpa , based on the study by Vollesen (1986), in which it was shown that ‘ S. cuneifolia ’ in Ethiopia and East Africa comprises five species, of which two are widespread in disturbed places ( S. schimperiana and S. tenuicarpa ) and three are more localised in East Africa, while S. cuneifolia is an Indian species not found in Africa. Since Van Someren (1974) lists S. schimperiana separately, I suggest his record of S. cuneifolia can be attributed to S. tenuicarpa . Van Someren (1974) also lists Hibiscus gossyphina , which appears to be a misspelling of H. gossypinus ; this name has been introduced by three different authors for different plants, two of which are unavailable homonyms (Tropicos 2015); as one of these has been treated as a synonym of H. fuscus , and I have found H. fuscus to be a food plant of H. spio , I suggest this is the species intended by Van Someren.

In Kenya, I have found early stages of S. spio on Hibiscus fuscus (Kadera God Forest, Ololua Forest) , H. calyphyllus (Ololua Forest) , Pavonia burchellii (as P. p at e ns; Muguga, Ngong Forest), Pavonia urens var. urens (roadside plants in open situations at 2600–3000 m in the Central Range in the vicinity of Nabkoi and Timboroa ), Sida rhombifolia ( Kadera God Forest , Nairobi ; Figure 7.2) and Triumfetta tomentosa (Kakamega Forest, MJWC 89 /44). In captivity, caterpillars collected on P. u re n s var. urens completed development on P. u re n s var. tomentosa .

I have also found a caterpillar of what appeared to be S. spio on Urena lobata (Kakamega Forest, MJWC 89/43), but was not able to rear it through and did not preserve the corpse; Vuattoux’s (1999) record from this plant provides support for my provisional identification. Of these Kenyan food plants, P. burchellii was the food plant on which caterpillars were most often found in the vicinity of Nairobi. At Cotonou, Bénin, I have found caterpillars on Waltheria indica , alongside those of S. diomus (MJWC 89/207). The diversity of these food plants, from low shrubs to tall herbs / small bushes, and from the very hairy, thick young leaves of P. ure n s to the thin smooth leaves of Sida spp. is striking, and suggests a variety of other Malvaceae will also prove to be suitable.

Ovum. I have not documented the ovum, but it is illustrated by G.C. Clark (in Dickson & Kroon 1978, Plate 16) and has regular ribs like those of S. diomus .

Leaf shelters. Limited observations indicate that young caterpillars until the final instar make a shelter from a single leaf by folding it upwards along the midrib. However, final instar caterpillars spin together two or three of the terminal leaves to make a shelter, as observed on Pavonia burchellii ( MJWC 88 /30, 88/53, 88/81, 89/38), Hibiscus calyphyllus ( MJWC 88 /40) and H. fuscus ( MJWC 88 /22). The younger caterpillars on Pavonia urens var. urens hide amongst the young terminal leaves which are thick, stiff and very hairy, and the mature caterpillars may pull two leaves or two halves of a leaf together with silk to form a loose shelter. A pupa collected on H. fuscus was in a folded leaf, of which the distal part had been eaten, or cut off ( MJWC 90 /82 A).

Caterpillar. In the final instar ( Figure 8 ), which grows to 21mm long, the head is rounded, slightly indent at vertex, 2.5 x 2.6mm wide x high (range 2.20–2.75 x 2.35–2.75, n=7); shiny, reticulate; variable in colour: (1) almost completely black (MJWC 90/63, Figure 8.3; MJWC 89/207 from Bénin), (2) black with barely discernible brown diffuse markings from apex parallel to epicranial suture and posterior to stemmata (MJWC 88/40, 90/82B, 90/84, Figure 8.1–2), (3) dark brown ground colour; a brown line from apex down middle of epicranium, widening slightly basally to level of bottom of frons; lateral to this line, anterolateral and lateral parallel brown lines in ventral half of face (MJWC 88/100, Figure 8.5), (4) face brown apart from epicranial suture broadly dark and frontal suture narrowly dark, laterally and dorsally dark, merging to almost black at posterior margin (MJWC 88/ 22B), or intermediate between (2) and (4) (MJWC 88/81C); the markings, if present, are more obvious when viewing the cast head capsule from the inside; individuals MJWC 88/22B, 88/81C and 88/100 (Figure 8.4) showed hints of a vertical row of three indistinct darker spots down each epicranium; the face sparsely covered with short, straggly, pale, weakly aciculate, recumbent or semi-recumbent setae, which may be entangled with the neighbouring setae; scattered pale, erect, simple setae over all head, short on face (0.3mm), longer and slightly barbed laterally and dorsally (up to 1.2mm); on labrum these are dark distally, some slightly clubbed; laterally and dorsally a few slightly longer, slightly barbed black setae (up to 1.4mm); overall the face appears indistinctly mottled in stripes and spots. T1 variable; typically black, with a furrow separating the posterior third; pale dorsal line wider at anterior margin; pale dorsolateral line wider at both anterior and posterior margin, with a brown oval plaque subdorsally near anterior margin; scattered, pale erect, simple setae of variable length, similar to those of head; legs pale brown. T1 of individuals MJWC 88/69 and 88/100 from P. u re ns are marked in dark-brown-black, pale brown and white; a broad white dorsal line; subdorsally anterior two-thirds pale brown with a small dark patch centrally adjacent to the white dorsal line, posterior third dark; a narrow, dark, line at edge of subdorsal area; a broad dorsolateral white band; a brown (anteriorly) and dark (posteriorly) patch laterally; ventral to this less dark; scattered pale, erect, simple setae varying from very short to comparable with those of head; legs brown. T1 of individual MJWC 88/22B was more generally pale, with a diffuse brown subdorsal patch in posterior two-thirds, the brown plaque on its anterior margin; short narrow, dark, lateral line just above dark spiracle. T1 of individual MJWC 90/84 was almost translucent, with a faint, dark, subdorsal patch in the posterior third only. Body green, pale yellow-green on anterior part of each segment, with slightly darker dorsal line; pair of black dots on each segment, about 1mm apart, on each side of dorsal line; another dot laterally on each segment; very faint whitish lateral line, a little dorsal to the inconspicuous pale brown spiracles; covered with erect, pale, simple setae as T1, of variable length up to about 1mm, on white bases; all legs concolorous.

A penultimate instar caterpillar of 9mm, collected on Hibiscus fuscus at Kadera God Forest (MJWC 90/82B) was the basis of the following description ( Figure 9 ). Head 1.7 x 1.7mm wide x high (range 1.45–2.20 x 1.45–2.08, n=5); similar to final instar; brown, darker laterally and dorsally, broadly along epicranial suture and narrowly on frontal sutures (in other examples, the head is uniformly dark brown (MJWC 88/81C), while others are intermediate (MJWC 89/38)); shiny, reticulate; covered with setae as final instar, the longest dark ones up to 1.0mm long; face with a vertical row of three brown spots on each epicranium, and a lateral brown spot. T1 brown with black pronotum, with pale patches dorsally and dorsolaterally. Body whitish green with longitudinal pale stripes; long white, simple setae.

The head of the n-2 instar caterpillar measured 1.0 x 1.0mm wide x high (range 0.90–1.00 x 0.89–1.08mm, n=4); uniformly brown, shiny, reticulate; a few short slightly aciculate setae on face; longer, pale, erect, simple setae laterally and dorsally, with slightly longer, slightly barbed, dark setae amongst these.

Pupa. The pupa ( Figure 10 ) is formed in the last leaf shelter; it is 10–12mm long and lightly covered with a white waxy bloom; generally smoothly contoured; the proboscis extends 1–2 segments beyond wing sheaths; cremaster elongate and pointed, about 2mm long; uniformly brown to dark brown in colour, apart from front of head which may be mottled in pale brown; spiracle T1 dark brown, 0.34 x 0.58 x 0.24mm wide x high x deep (range 0.28–0.40 x 0.50–0.64 x 0.18–0.30mm, n=5) on posterior margin; spiracles A 2– A 3 visible; abdominal spiracles dark, inconspicuous; a brown, shiny stripe with no setae down middle of eye; no plaques discernible but one pupa had small, round dark patches clear of wax on the anterior margin of A 2 and A 4, and dorsolaterally in the middle of the segment on A 2– A 4; erect, pale or pale brown, simple setae on head and thorax; semi-recumbent, pale or pale brown, simple setae on abdomen, especially posterior margin of segments. The pupa turns progressively darker as it develops and emerges after 13–21 days. The specimen reared by Sevastopulo (unpublished) took 12 days in Kampala.

Material reared in Bénin ( MJWC 90 /207C–D) differed in that there was no white waxy bloom; the pupa was uniformly dark brown, with contrasting white setae.

Natural enemies. The caterpillars are parasitized by a solitary ichneumonoid endoparasitoid (Muguga, MJWC 88 /81; Ololua Forest, MJWC 88 /22 A, 88/30) which causes the caterpillar to form a premature pupal shelter. The parasitoid larva then emerges and spins a tough grey-brown cocoon 6mm long, within the shelter, and emerges 10– 12 days later. This species also parasitizes S. colotes Druce (below).

Caterpillars which I believe to have been this species are also attacked by a gregarious Microgasterinae species, the larvae of which emerge from the mature caterpillar and spins their cocoons in the leaf shelter, emerging about 11 days later. A brood from Pavonia burchellii in Ngong Forest consisted of 1 males and 9 females ( MJWC 89 /38) and one from Sida ? rhombifolia in Nairobi , consisted of 7 males and 17 females ( MJWC 88 /38), whereas one from P. u re n s near Nabkoi had probably already partially emerged when collected, as only two adults emerged ( MJWC 88 /69).

Dickson & Kroon (1978, Plate 16) record that this species is attacked by several Tachinidae , including Thecocarcelia latifrons Mesnil which is a larval-pupal parasitoid. Crosskey (1984) recognised seven sub-Saharan African species of Thecocarcelia , noting that there was no available identification key, a revision needed, and that there were several apparently undescribed species in the Natural History Museum, London. Working on the Oriental fauna, Shima (1999) recognises that Thecocarcelia as now defined is host specific to Hesperiidae . He also notes that the egg is large and its chorion is very thin and membranous, implying that the larva would either hatch immediately after the egg was laid on its host or that it would hatch just before the newly hatched larva was deposited on the host. To do this the female Thecocarcelia sp. would have to find the host caterpillar feeding outside its shelter, or make its way into the shelter.

Discussion. G.C. Clark’s paintings of the life history (in Dickson & Kroon 1978, Plate 16) shows a rather similar life history to that documented here, but with some apparent differences. The caterpillar body in Clark’s work is almost white, whereas in Figures 8 and 9 it is distinctly yellow-green; T1 is marked in black and white similarly to Figure 8.1–2, but not Figures 8.3–5 and 9.2; the head appears to have dark setae, but not the intermixed pale ones as in Figures 8 and 9 ; the frontal view of the face is rather uniform rather than indistinctly marked. In contrast, the caterpillar shown by Henning et al. (1997, p. 115) is a good match to some of those shown here, e.g. Figure 8.3.

Figures

FIGURE 8. Final instar caterpillars of Spialia spio. 1, lateral view; collected as final instar and on Hibiscus calyphyllus, Ololua Forest, Nairobi, 8 May 1988; photographed 8 May; pupated 15 May; 21 mm; MJWC 88 / 40; 2, detail of head, as # 1. 3, dorsolateral view; collected as young caterpillar on Pavonia urens, near Nabkoi, 2600 m, 1 Jul 1990; moulted to final instar 30 Jul; photographed 10 Aug; pupated 16 – 20 Aug; 18 mm; MJWC 90 / 63; 4, detail of head, as # 3. 5, detail of head; collected as final instar caterpillar on Pavonia urens, near Timboroa, 23 Oct 1988; photographed 23 Oct; pupated 5 Nov; MJWC 88 / 100.

FIGURE 9. Penultimate instar caterpillar of Spialia spio. 1, dorsolateral view; collected on H. fuscus, Kadera God Forest, near Kisii, 5 Aug 1990; photographed 8 Aug; moulted to final instar 13 Aug; 9 mm; MJWC 90 / 82 B; 2, detail of head and anterior body, collected as small caterpillar on Waltheria indica, Cotonou, Bénin, 30 May 1989; photographed 22 Jun; pupa 8 Jul; MJWC 89 / 207 C.

FIGURE 10. Pupa of Spialia spio, Kenya. 1, lateral view; collected as small caterpillar on Pavonia burchellii, Muguga, 15 Sep 1988; pupated and photographed 23 Oct; adult 5 Nov; MJWC 88 / 81 C. 2, as # 1; photographed 26 Oct 1988.