Volume 26: 1–3 METAMORPHOSIS ISSN 1018–6490 (PRINT) LEPIDOPTERISTS’ SOCIETY OF AFRICA ISSN 2307–5031 (ONLINE)

NOTE Oviposition and mating behaviour in Orachrysops warreni G.A. & S.F. Henning, 1994 (: : ), in Mpumalanga, South Africa Published online: 3 February 2015

Christopher K. Willis1 & David A. Edge2

1 South African National Biodiversity Institute (SANBI), Private Bag X101, Silverton 0184. E-mail: [email protected] 2 P O Box 2586, Knysna 6570, South Africa. E-mail: [email protected]

Copyright © Lepidopterists’ Society of Africa

INTRODUCTION restricted distribution, it was classified in the South African Red Data Book for as Least Orachrysops warreni G.A. & S.F. Henning, 1994 Concern (Mecenero et al., 2013). Adults of this (Warren’s Blue) was discovered by R.T. Warren and presumably univoltine species have only been his family during surveys conducted for the then recorded flying from the middle of December into Transvaal Nature Conservation Division, in the January, with the remainder of the year being spent Verloren Valei Nature Reserve (VVNR), 10 km as larvae and pupae. Its montane grassland habitat is north of Dullstroom in Mpumalanga, in December classified as Lydenburg Montane Grassland (Gm 18 1988 and December 1989 (Warren 1990a, b). in Mucina & Rutherford, 2006). Amongst the specimens collected were a new species of Orachrysops, subsequently described (Henning & Henning, 1994). The was named after its discoverers, the Warren family. It has to date only been recorded from inside the VVNR, its type locality, which is currently managed by the Mpumalanga Tourism & Parks Agency (MTPA).

OBSERVATIONS

Verloren Valei Nature Reserve

The VVNR, comprising an area of 5,891 ha, was proclaimed as a nature reserve in 1983, and is known for its rolling montane grasslands, quartzite ridges, near-pristine natural wetlands and marshy habitats (Fig. 1). It is situated in a summer rainfall zone with a mean annual rainfall of 840 mm, falling mainly in the form of summer thunderstorms between October and March. Mist is common in the area, as is frost, Figure 1 – Location map: Verloren Valei Nature Reserve occurring between March and September. At least 50 Oviposition behaviour and larval host plant butterfly species have been recorded from the reserve (Warren 1990b). On 19–20 December 2004 the second author visited

the VVNR and searched the area shown in Fig. 2 for Orachrysops warreni evidence of the host plant of O. warreni. At site 3 Orachrysops warreni, an extremely rare, some hatched ova were found on Indigastrum myrmecophilous endemic South African butterfly is fastigiatum (E.Mey.) (Fabaceae). Site 4 is a gently currently only known from a single quarter degree sloping amphitheatre with an erosion channel grid square (2530AC), although it could possibly bisecting it, up and down which male O. warreni occur in suitable grassland habitat where its larval were flying. The same Indigastrum species was host plant (see below) grows on farms surrounding found were the males were flying, and this seemed the VVNR. Although O. warreni has a very to confirm that this was indeed the host plant, although no females were seen. A little later and Received: 6 January 2015 higher up near some rocks a female was found Accepted: 3 February 2015 fluttering around another plant, Indigofera dimidiata Copyright: This work is licensed under the Creative Vogel ex Walp. (sensu stricto) (Fabaceae). A freshly Commons Attribution-NonCommercial-NoDerivs 3.0 laid pale blue ovum was found on the underside of Unported License. To view a copy of this license, send a the large, soft, trifoliate leaves (GPS 25o18ʹ24ʹʹS, letter to Creative Commons, Second Street, Suite 300, San o Francisco, California, 94105, USA, or visit: http://creative 30 08ʹ32ʹʹE, 2095 m asl). Typically the ♀s landed on commons.org/licenses/by-nc-nd/3.0/ the inflorescence, took nectar, and then crawled

Willis & Edge/ Metamorphosis 26: 1–3 2

individuals of O. warreni flying during a survey of the VVNR in December 2008 (Fig. 3), and submitted the pictures to the Demography Unit’s (ADU) SABCA Virtual Museum. Regular visits have subsequently been made in either December or January. O. warreni adults, which were most often flying around patches of a red-flowered Indigofera (Fig. 4), were seen during each visit to the reserve. The second author confirmed that this was indeed Indigofera dimidiata, on which he had observed oviposition in December 2004.

Figure 2 – Area searched for host plant of O. warreni, with contour elevations and sites where ova were discovered. down the peduncle to reach the leaves, closer to the ground (see Fig. 4). Eggs were most frequently laid on the underside of the leaflets, but less often on the leaflet uppersides, the leaf-like stipules or even on the stems. Other subpopulations of O. warreni were found in the general area, always where I. dimidiata occurred. Although the Indigastrum species and another Indigofera were present in the vicinity the female O. warreni were only seen to lay on Figure 4 – Indigofera dimidiata (C. K. Willis)

I. dimidiata. It was concluded that the eggs found on Then on 23 December 2014, exactly 25 years after I. fastigiatum must have been laid by Orachrysops the type specimens were obtained by R.T. Warren, lacrimosa (Bethune-Baker), which flies from the first author made the following observations of November to early December, before O. warreni the mating behaviour of O. warreni (GPS emerges. Ten O. warreni ova were collected and 25o18ʹ06ʹʹS, 30o08ʹ46ʹʹ, 2150 m asl). taken home to Knysna, where they hatched between

9 to 11 days later. Only one larva survived to the second instar because of shortage of host plant. It was a creamy colour with fine dark spots “sprinkled” on the dorsal surface of most segments, similar to the larva of O. niobe (Trimen). A dorsal nectar organ was present but no tentacle organs were seen on the larva.

Figure 5 – Mating frenzy by a group of O. warreni. (C. K. Willis)

Male and female O. warreni were initially flying around a patch of I. dimidiata, with little interaction. Shortly thereafter, at c. 13h30, a group of O. warreni males, as if responding to some trigger or chemical signal, were suddenly observed descending on a female and a frenzy of activity and movement was Figure 3 – Female Orachrysops warreni (C. K. Willis) noted. The group of 5–6 males descended together

into a patch of grass, competing with one another for Mating behaviour the available female (Fig. 5). After some 10-15 The first author initially observed and photographed seconds of this frenzied activity, a single male and Willis & Edge/ Metamorphosis 26: 1–3 3 the female were found in copula (Fig. 6), whilst the other unsuccessful males had flown off.

Figure 6 – Mating pair of O. warreni (C. K. Willis)

ACKNOWLEDGEMENTS

Dr. Brian Schrire of Kew Gardens for identifying the Indigastrum and Indigofera species for the second author in 2005, and the Indigofera photographed by the first author (Figure 4) in 2014. Ms Balungile Bengu and Ms Nonhlanhla Mdladla of the MTPA are thanked for allowing the first author access to the VVNR. VVNR location map courtesy of Dr Mervyn Lötter, MTPA.

LITERATURE CITED

MECENERO, S., BALL, J.B., EDGE, D.A., HAMER, M.L., HENNING, G.A., KRÜGER, M., PRINGLE, E.L., TERBLANCHE, R.F. & WILLIAMS, M.C. (eds). 2013. Conservation assessment of butterflies of South Africa, Lesotho and Swaziland: Red List and atlas. Saftronics (Pty) Ltd., Johannesburg & Animal Demography Unit, Cape Town. MUCINA, L. & RUTHERFORD, M.C. (eds) 2006. The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria. HENNING, G.A. & HENNING, S.F. 1994. A review of the Orachrysops Vári (Lepidoptera: Lycaenidae) with descriptions of seven new species and one new subspecies. In: E.L. Pringle, G.A. Henning & J.B. Ball (eds) 1994. Pennington’s Butterflies of Southern Africa. Second edition. Struik Winchester, Cape Town: 260–273. WARREN, R.T. 1990a. Report on day trip to Verloren Valei Nature Reserve. Metamorphosis 1(25): 28–30. WARREN, R.T. 1990b. Checklist for Verloren Valei Nature Reserve. Metamorphosis 1(25): 30–31. WILLIAMS, M.C. 2014. Afrotropical Butterflies. http://www.metamorphosis.org.za/?p=articles&s =atb.