PHAON n°2 - Jul 2005

PHAON (Pinhey's Heritage African Odonata Network) - July 2005

Wings in the whirlpool: in search of dragonflies in the heart of the Congo Basin

Klaas-Douwe B. Dijkstra, Gortestraat 11, NL-2311 MS Leiden, The Netherlands (dijkstra@nnm.nl)

Called an "evolutionary whirlpool" by Jonathan Kingdon, the Congo Basin is one of the most interesting parts of Africa for Odonata. From west to east it connects the continent's main rainforests with its main highlands, to the north and south it gently grades through a mosaic of forest, woodland and savannah towards the dry lands of the Sahara and Kalahari. With its forests, rivers and swamps, the basin itself is and endless succession of prime odonate habitat. Africa's wet heart is the centre of diversity of several genera, especially in Libellulidae, including poorly known ones like Aethiothemis, Lokia, Porpax and the aptly named Congothemis. We largely owe our knowledge of the Congolese fauna to the efforts of Belgian collectors who assembled their material in the 1930s to 1960s. Almost no research took place in the last three decades of the 20th century, while earlier efforts were concentrated in a handful of peripheral regions (e.g. Katanga , Parc National de la Garamba). The knowledge of most of the lower basin ('cuvette') is therefore negligible. No wonder that an invitation to join Conservation International's biodiversity assessment of the Lokutu area, on the Congo River about 250 km downstream from Kisangani, turned a long cherished dream into excited sleepless nights. On 27 October 2004 seven biologists, including myself, took a small aeroplane from Kinshasa (Democratic Republic of Congo) across the basin to our destination. Tracing a perfect straight line across the completely flat land below us, we flew over 800 km of infinite forest, interrupted only occasionally by a snaking river or an isolated hamlet.

Because no prior research of Odonata has been undertaken in the Lokutu region, or even anywhere near it, any result would be surprising. The total of 86 species found was high, especially considering only 27% were widespread Afrotropical species. By comparison, the well studied Bwindi Impenetrable and Semliki National Parks, both in Uganda on the DRC border, have 65 and 91 species respectively, of which 31% and 48% are widespread species. The Lokutu area thus has a richer fauna of localised, generally forest-associated, odonates. Ubiquitous well-dispersing species, like Crocothemis and red Trithemis species were totally lacking, even in disturbed habitats. Equally notable was the paucity of some characteristic Congo Basin species. The only sign of the endemic libellulid diversity were single specimens of Congothemis trithemoides and Hadrothemis vrijdaghi. The observed poverty of certain Congolian specialities is probably explained by the selection of habitats encountered. The flight back over the basin revealed numerous other habitat types that are likely to hold these species, such as forested and open swamps, seasonally flooded forest, oxbows and medium-sized rivers. These all have stagnant or slow-flowing water, while the wealth of encountered species lay in Zygoptera and Gomphidae that principally inhabit faster flowing water. Indeed the diversity of running-water forest species (29 species; i.e. 35%) lay above that of Semliki (23; 25%) and Bwindi (23; 35%).

Logically, many of my records constituted range extensions: for instance Pseudagrion simplicilaminatum and Phyllogomphus coloratus were not known east of Congo-Brazzaville. Chlorocypha pyriformosa was not even known east of Nigeria , but the discovered populations were somewhat aberrant. Ceriagrion ignitum was so far only known from the Ghanaian type series and its rediscovery in an anthropogenic habitat 2700 km to the east came as a surprise: numerous egg-laying pairs were found on sheltered ponds covered by Salvinia, but the first specimens were caught at a disused swimming pool! Three discoveries appeared to be new to science. Finding very distinctive new species of the conspicuous but small genera Platycypha and Mesocnemis was remarkable. A third probable novelty, in the difficult genus Elattoneura, is also numerous in the Belgian collections.

At Lokutu the Congo River is over 3 km broad, fragmented by numerous forested islands. Because adults emerge at night and are rarely seen afterwards, river species like gomphids are seldom collected. Daytime reveals little of interest along the shores, but at dusk the middle course (as far as 1 km from the bank) comes alive with large uncatchable anisopterans that swiftly skim the surface. Perhaps this is the main time and place of reproductive activity. A couple hours spent scouring the banks in the morning revealed many interesting exuviae and a few emerging adults. I then realized I should take a canoe and flashlight out around midnight. Within an hour I found emerging Neurogomphus and Phyllogomphus, probably becoming the first to witness this in the field. At least seven gomphid species in seven different (sub)genera reproduced in the river: Gomphidia bredoi, Ictinogomphus regisalberti, Lestinogomphus sp., Neurogomphus (Mastigogomphus) cf. chapini, N. (Neurogomphus) cf. uelensis, Paragomphus acuminatus and Phyllogomphus coloratus. This odonate diversity in one of Earth's largest rivers was one of the survey's most interesting results. Unfortunately I did not think of a midnight boat trip until the last evening, but I intend to make moonlight riverside paddling a priority in the future!

"A Fieldguide to the Damselflies of South Africa " by Warwick & Michle Tarboton (2005)

This 95-page full-colour fieldguide (ISBN 0-620-33878-4) is the sequel to the anisopteran book produced by the same authors in 2002. "Tarboton 2", dedicated to B.I. Balinsky, is another splendid achievement! The new book has the same format, but the quality of the images is even better and many of the small imperfections of the first guide have been avoided, making this one even better. Each species has about a full page and is illustrated with several enlarged dorsal and lateral scans of fresh specimens. All species have a distribution map, a brief description and usually a natural photograph of a male. It is a delight to see the vivid colours of all the species, especially of the nation's endemic synlestids! Simple pictorial keys direct the user to the right pages. The general introduction is kept to an absolute minimum, but the choice of vernacular English and Afrikaans names is addressed. The authors were previously criticized for introducing alternatives to names previously used in South Africa . They argue that names evolve and their objective has been to remain close to scientific names in coining vernaculars. I recommend some of the more imaginative alternatives and will certainly adopt Riverjack for the bold Mesocnemis singularis. Cherry-eye Sprite for the widespread Pseudagrion sublacteum is also very apt and attractive. More than a third of the zygopterans covered is endemic to South Africa , while the majority of the anisopterans are widespread Afrotropical species. That makes the new guide slightly less applicable elsewhere in the continent than the first book. Still I recommend this unequalled book to anyone with any interest in Africa's odonates. Order both guides directly from the authors (wtarbotn@iafrica.com). We must hope that Warwick and Michle will now work towards an updated edition incorporating both suborders!

KD Dijkstra

232 year old puzzle finally solved: Palpopleura lucia and P. portia are distinct species!

Klaas-Douwe B. Dijkstra, Gortestraat 11, NL-2311 MS Leiden, The Netherlands (dijkstra@nnm.nl)

Libellula lucia and L. portia were the first true odonates to be described from tropical Africa, 232 years ago. The two, among the most familiar and often photographed dragonflies in the continent, have long been treated as forms of a single species, Palpopleura lucia. In a recent study Mitchell & Samways (2005) compared the DNA of several specimens of both and two additional Palpopleura species, all from the same locality. This showed unequivocally that lucia and portia are distinct, but closely related, species. It is worth adding that, besides well-known differences in size and wing coloration (lucia is larger and darker, see O'Neill & Paulson 2001), the two differ in pruinosity pattern and penis morphology. The latter was already illustrated 111 years ago by Karsch (1894, marginata is a synonym of lucia)! Mature males of portia have the mesepisterna pruinose but the abdomen black-tipped (S9-10 not pruinose), while in lucia the mesepisterna remain mat black but the abdomen becomes entirely pruinose. Pinhey (1982) mentioned intermediates between lucia and portia from Cameroon, the Central African Republic, the Congos and Gabon. These were probably dark portia from warm and wet regions, with blacker wings with a less apparent portia-pattern. There is no type material of the two taxa, but they are illustrated well by Drury (1773). His portia illustration clearly shows a male as known by that name, but the depicted lucia is female. To my knowledge, this sex cannot yet be safely identified. Still, the identity of the two species is commonly accepted. This brings me to a small criticism of the Mitchell & Samways paper: The wing figure of "lucia" shows a male portia, that of "portia" a female of either form. Despite this the paper elegantly demonstrates how new molecular techniques can solve old problems.

Drury, D., 1773. Illustrations of natural history; wherein are exhibited upwards of two hundred and forty figures of exotic insects, according to their different genera, being engraved and coloured from nature, with the greatest accuracy, and under the authors own inspection, on fifty copper-plates; with a perticular description of each insect... to which is added a translation into French, 2. White, London.

Karsch, F., 1894. Libellen von der deutschen Forschungs-Station Yande im Hinterlande von Kamerun, gesammelt von Herrn G. Zenker. Berliner entomologische Zeitschrift 39 (1): 11-16.

Mitchell, A. & M.J. Samways, 2005. The morphological 'forms' of Palpopleura lucia (Drury) are separate species as evidenced by DNA sequencing (Anisoptera: Libellulidae). Odonatologica 34 (2): 173-178.

O'Neill, G. & D.R. Paulson, 2001. An annotated list of Odonata collected in Ghana in 1997, a checklist of Ghana Odonata, and comments on West African odonate biodiversity and biogeography. Odonatologica 30 (1): 67-86.

Pinhey, E., 1982. Odonata collected in Ethiopia III. Anisoptera. Problemi attuali di scienza e di cultura (III) 252: 1-56.

Lake Malawi's Dancing Jewel: Elliot Pinhey's letters to its discoverer John Wilson

Klaas-Douwe B. Dijkstra, Gortestraat 11, NL-2311 MS Leiden, The Netherlands (dijkstra@nnm.nl)

Chlorocyphidae, especially the common Dancing Jewel (Platycypha caligata) of tropical eastern Africa, are known for their bright coloration and showy displays. To quote Elliot C.G. Pinhey (1965): "The female rests on a twig in seemingly bored contemplation while the male performs a little aerial dance, backwards and forwards in the arc of a circle, orientated towards the female and dangling the white surfaces of the tibiae below his head like a beard. If competition is keen, however, such formalities are generally omitted and he merely pounces on her without any prelude". In August 1981, Pinhey presented a paper at the international symposium of odonatology in Chur, Switzerland, titled "Platycypha caligata (Selys) and a new lacustrine morph (Odonata: Chlorocyphidae)" (see photograph in Dijkstra et al. 2003). The presentation formed the outcome of his investigation of Platycypha specimens collected on the shore of Lake Malawi, and an intensive correspondence with their collector, John G. M. Wilson.

In January 2002, I met both the collector and the collected, which shedded new light on Lake Malawi's Platycypha. Quotes from Pinhey's letters to Wilson in 1980, that the latter has kindly allowed me to reproduce, neatly summarise Pinhey's interpretation of the Malawi specimens. He first mentioned them in a letter dated 2 April: "The species of particular interest, and for which this letter is written is a new Platycypha. [.] Do see if you can find more, including the female, a duller looking girl. [...] Platycypha like fast running streams, often in shade, settling on branches or on rocks. [.] I have long suspected there must [emphasis by Pinhey] be a new species of Platycypha or Chlorocypha in Malawi." Twenty days later, following a reply with ecological details from Wilson, he continued: "The ecology of that Platycypha is most intriguing, inhabiting rocks on lake shore. [.] I must find time to write up this new species. [.] I will hope to name it after its discoverer! If you could possibly pickle a mature male in 75% alcohol immediately on capture it would help in the description." Pinhey elaborated on 6 June: "A lake breeder is quite remarkable [.]. Your colour photos will help in checking colours of the male." On 30 June he apologized: "I am sorry I put you to so much trouble over the reproduction of living colours of your new Platycypha and, particularly, in the great misfortune of losing your close-up lens. I am sorry if this resulted from my persuasion. [...] When I suggested alcohol I had no idea this universal fluid would be so hard to obtain in its preservative form."

After receiving the photographs and alcohol material Pinhey altered his opinion, as evidenced by a letter dated 3 July: "The colour slides are excellent but [have not] solved the problem in the expected manner! There were three original male Platycypha [.] Two showed peculiar markings on abdominal segments 4-5 which seemed distinctive but the third was different, rather nearer caligata. That is why I asked for a pickled example (or photos) in order to clarify the markings and to see if there was any overall colour difference. The colour photos show the male to be the same colour as mature caligata and [.] proves that there is really no definite pattern difference from that species. I am still working on other characters, but I am sorry to say they appear to be caligata after all, and at most there may be differences developed from a change in ecological conditions. The unusual habits in themselves will be worth describing apart from any morphological characters there may be. I am sorry to disappoint you (and myself)." Six days later he expanded: "I should have expected staining [.] However, I am developing a possible distinction for the lake populations. Out of 150 male caligata examined from many parts of Africa your nine lake males are invariably smaller than all the rest, except for another male (singleton) which R. C. Wood sent me in August 1961 from the lake shore at Cape Maclear! This seems significant. Moreover their tibial expansions are less than average for other populations. [.] Thus, there does seem reason to believe that at least the ecology has resulted in some [emphasis by Pinhey] difference, particularly in diminishing size. [.] I will [.] continue on a paper outlining the supposition that Platycypha caligata has adapted to both riverine and lacustrine environments, unlike other known African species of the family. This in itself is of much interest. It is unlikely, I suppose, that any freshwater fish show similar tendencies to modify under such changes?" The final question directed at Wilson, a fisheries biologist, is remarkable considering Lake Malawi's fame for its profusion of endemic species of specialized cichlid fish. On 10 December Pinhey concluded: "In August next year I will read my paper on your lacustrine Platycypha to the World's Odonata gathering in Switzerland. Your name will be uppermost in the script." In the proceedings resulting from the paper read, Pinhey (1982) described the Lake Malawi specimens as a form of Platycypha caligata. The Lake Malawi examples are constantly smaller than specimens from throughout the species's range, but differences in coloration were dismissed by Pinhey (1982), who stated: "The [initial] three males seemed at first to have unusual but rather consistent markings [.] Further examination [.] showed that these markings were only post-mortem discoloration changes."

During a visit to a rocky islet 2 km off the lake coast on 1 January 2002, I encountered numerous Platycypha specimens. The first impression was of a much smaller and darker insect than typical caligata. Some males had the basal segments darkened, a condition not occurring in caligata, while others had the typical all-blue abdomen. Mature males were found perched near the waterline, whereas females and teneral males were abundant among the bushes that crowned the isle. It appeared that S1-5 become extensively melanised with age, which is not seen in typical riverine P. caligata. Presumably the resulting difference in markings initially lead Pinhey to conclude this was a new species, but he only received additional material and photographs of young specimens. He thus decided the differences were caused by staining, describing the lacustrine Platycypha as a mere form. From the research history illustrated by Pinhey's quotes and his emphasis on colour patterns therein, it may be deduced that he would have regarded the Lake Malawi specimens as a good species if he had known the nature of their coloration. At the Chala crater lake on the Kenya-Tanzania border, P. caligata is similarly small, but does not darken with age (V. Clausnitzer pers. comm.). Molecular studies may prove that Lake Malawi is home to an endemic species of Platycypha, and not just dwarfed specimens of P. caligata as seen at Lake Chala.

Dijkstra, K.-D.B., A. Martens & M.J. Parr, 2003. Proceedings of the 1st PHAON Meeting on African Odonata, Gllivare, 26 July 2001, Foreword, African Odonatology: past, present and future. Cimbebasia 18: 161-166.

Pinhey, E., 1965. Development of the study of Odonata (Dragonflies) in Central Africa. Proceedings of the Central African Scientific and Medical Congress, Lusaka, Northern Rhodesia, 26-30 August, 1963. Pergamon Press, Oxford 321-331.

Pinhey, E., 1982. Platycypha caligata (Selys) and a new lacustrine morph (Odonata: Chlorocyphidae). Advances in Odonatology 1: 213-225.


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PHAON (Pinhey's Heritage African Odonata Network) - July 2005 Wings in the whirlpool: in search of dragonflies in the heart of the Congo Basin Klaas-Douwe B. Dijkstra, Gortestraat 11, NL-2311 MS Leiden, The Netherlands (dijkstra@nnm.nl) Called an "evolutionary whirlpool" by Jonathan Kingdon, the Congo Basin is one of the most interesting parts of Africa for Odonata. From west to east it connects the continent's main rainforests with its main highlands, to the north and south it gently grades through a mosaic of forest, woodland and savannah towards the dry lands of the Sahara and Kalahari. With its forests, rivers and swamps, the basin itself is and endless succession of prime odonate habitat. Africa's wet heart is the centre of diversity of several genera, especially in Libellulidae, including poorly known ones like Aethiothemis, Lokia, Porpax and the aptly named Congothemis. We largely owe our knowledge of the Congolese fauna to the efforts of Belgian collectors who assembled their material in the 1930s to 1960s. Almost no research took place in the last three decades of the 20th century, while earlier efforts were concentrated in a handful of peripheral regions (e.g. Katanga , Parc National de la Garamba). The knowledge of most of the lower basin ('cuvette') is therefore negligible. No wonder that an invitation to join Conservation International's biodiversity assessment of the Lokutu area, on the Congo River about 250 km downstream from Kisangani, turned a long cherished dream into excited sleepless nights. On 27 October 2004 seven biologists, including myself, took a small aeroplane from Kinshasa (Democratic Republic of Congo) across the basin to our destination. Tracing a perfect straight line across the completely flat land below us, we flew over 800 km of infinite forest, interrupted only occasionally by a snaking river or an isolated hamlet. Because no prior research of Odonata has been undertaken in the Lokutu region, or even anywhere near it, any result would be surprising. The total of 86 species found was high, especially considering only 27% were widespread Afrotropical species. By comparison, the well studied Bwindi Impenetrable and Semliki National Parks, both in Uganda on the DRC border, have 65 and 91 species respectively, of which 31% and 48% are widespread species. The Lokutu area thus has a richer fauna of localised, generally forest-associated, odonates. Ubiquitous well-dispersing species, like Crocothemis and red Trithemis species were totally lacking, even in disturbed habitats. Equally notable was the paucity of some characteristic Congo Basin species. The only sign of the endemic libellulid diversity were single specimens of Congothemis trithemoides and Hadrothemis vrijdaghi. The observed poverty of certain Congolian specialities is probably explained by the selection of habitats encountered. The flight back over the basin revealed numerous other habitat types that are likely to hold these species, such as forested and open swamps, seasonally flooded forest, oxbows and medium-sized rivers. These all have stagnant or slow-flowing water, while the wealth of encountered species lay in Zygoptera and Gomphidae that principally inhabit faster flowing water. Indeed the diversity of running-water forest species (29 species; i.e. 35%) lay above that of Semliki (23; 25%) and Bwindi (23; 35%). Logically, many of my records constituted range extensions: for instance Pseudagrion simplicilaminatum and Phyllogomphus coloratus were not known east of Congo-Brazzaville. Chlorocypha pyriformosa was not even known east of Nigeria , but the discovered populations were somewhat aberrant. Ceriagrion ignitum was so far only known from the Ghanaian type series and its rediscovery in an anthropogenic habitat 2700 km to the east came as a surprise: numerous egg-laying pairs were found on sheltered ponds covered by Salvinia, but the first specimens were caught at a disused swimming pool! Three discoveries appeared to be new to science. Finding very distinctive new species of the conspicuous but small genera Platycypha and Mesocnemis was remarkable. A third probable novelty, in the difficult genus Elattoneura, is also numerous in the Belgian collections. At Lokutu the Congo River is over 3 km broad, fragmented by numerous forested islands. Because adults emerge at night and are rarely seen afterwards, river species like gomphids are seldom collected. Daytime reveals little of interest along the shores, but at dusk the middle course (as far as 1 km from the bank) comes alive with large uncatchable anisopterans that swiftly skim the surface. Perhaps this is the main time and place of reproductive activity. A couple hours spent scouring the banks in the morning revealed many interesting exuviae and a few emerging adults. I then realized I should take a canoe and flashlight out around midnight. Within an hour I found emerging Neurogomphus and Phyllogomphus, probably becoming the first to witness this in the field. At least seven gomphid species in seven different (sub)genera reproduced in the river: Gomphidia bredoi, Ictinogomphus regisalberti, Lestinogomphus sp., Neurogomphus (Mastigogomphus) cf. chapini, N. (Neurogomphus) cf. uelensis, Paragomphus acuminatus and Phyllogomphus coloratus. This odonate diversity in one of Earth's largest rivers was one of the survey's most interesting results. Unfortunately I did not think of a midnight boat trip until the last evening, but I intend to make moonlight riverside paddling a priority in the future! "A Fieldguide to the Damselflies of South Africa " by Warwick & Michle Tarboton (2005) This 95-page full-colour fieldguide (ISBN 0-620-33878-4) is the sequel to the anisopteran book produced by the same authors in 2002. "Tarboton 2", dedicated to B.I. Balinsky, is another splendid achievement! The new book has the same format, but the quality of the images is even better and many of the small imperfections of the first guide have been avoided, making this one even better. Each species has about a full page and is illustrated with several enlarged dorsal and lateral scans of fresh specimens. All species have a distribution map, a brief description and usually a natural photograph of a male. It is a delight to see the vivid colours of all the species, especially of the nation's endemic synlestids! Simple pictorial keys direct the user to the right pages. The general introduction is kept to an absolute minimum, but the choice of vernacular English and Afrikaans names is addressed. The authors were previously criticized for introducing alternatives to names previously used in South Africa . They argue that names evolve and their objective has been to remain close to scientific names in coining vernaculars. I recommend some of the more imaginative alternatives and will certainly adopt Riverjack for the bold Mesocnemis singularis. Cherry-eye Sprite for the widespread Pseudagrion sublacteum is also very apt and attractive. More than a third of the zygopterans covered is endemic to South Africa , while the majority of the anisopterans are widespread Afrotropical species. That makes the new guide slightly less applicable elsewhere in the continent than the first book. Still I recommend this unequalled book to anyone with any interest in Africa's odonates. Order both guides directly from the authors (wtarbotn@iafrica.com). We must hope that Warwick and Michle will now work towards an updated edition incorporating both suborders! KD Dijkstra *232 year old puzzle finally solved: Palpopleura lucia* and P. portia are distinct species!** Klaas-Douwe B. Dijkstra, Gortestraat 11, NL-2311 MS Leiden, The Netherlands (dijkstra@nnm.nl) Libellula lucia and L. portia were the first true odonates to be described from tropical Africa, 232 years ago. The two, among the most familiar and often photographed dragonflies in the continent, have long been treated as forms of a single species, Palpopleura lucia. In a recent study Mitchell & Samways (2005) compared the DNA of several specimens of both and two additional Palpopleura species, all from the same locality. This showed unequivocally that lucia and portia are distinct, but closely related, species. It is worth adding that, besides well-known differences in size and wing coloration (lucia is larger and darker, see O'Neill & Paulson 2001), the two differ in pruinosity pattern and penis morphology. The latter was already illustrated 111 years ago by Karsch (1894, marginata is a synonym of lucia)! Mature males of portia have the mesepisterna pruinose but the abdomen black-tipped (S9-10 not pruinose), while in lucia the mesepisterna remain mat black but the abdomen becomes entirely pruinose. Pinhey (1982) mentioned intermediates between lucia and portia from Cameroon, the Central African Republic, the Congos and Gabon. These were probably dark portia from warm and wet regions, with blacker wings with a less apparent portia-pattern. There is no type material of the two taxa, but they are illustrated well by Drury (1773). His portia illustration clearly shows a male as known by that name, but the depicted lucia is female. To my knowledge, this sex cannot yet be safely identified. Still, the identity of the two species is commonly accepted. This brings me to a small criticism of the Mitchell & Samways paper: The wing figure of "lucia" shows a male portia, that of "portia" a female of either form. Despite this the paper elegantly demonstrates how new molecular techniques can solve old problems. Drury, D., 1773. Illustrations of natural history; wherein are exhibited upwards of two hundred and forty figures of exotic insects, according to their different genera, being engraved and coloured from nature, with the greatest accuracy, and under the authors own inspection, on fifty copper-plates; with a perticular description of each insect... to which is added a translation into French, 2. White, London. Karsch, F., 1894. Libellen von der deutschen Forschungs-Station Yande im Hinterlande von Kamerun, gesammelt von Herrn G. Zenker. Berliner entomologische Zeitschrift 39 (1): 11-16. Mitchell, A. & M.J. Samways, 2005. The morphological 'forms' of Palpopleura lucia (Drury) are separate species as evidenced by DNA sequencing (Anisoptera: Libellulidae). Odonatologica 34 (2): 173-178. O'Neill, G. & D.R. Paulson, 2001. An annotated list of Odonata collected in Ghana in 1997, a checklist of Ghana Odonata, and comments on West African odonate biodiversity and biogeography. Odonatologica 30 (1): 67-86. Pinhey, E., 1982. Odonata collected in Ethiopia III. Anisoptera. Problemi attuali di scienza e di cultura (III) 252: 1-56. Lake Malawi's Dancing Jewel: Elliot Pinhey's letters to its discoverer John Wilson Klaas-Douwe B. Dijkstra, Gortestraat 11, NL-2311 MS Leiden, The Netherlands (dijkstra@nnm.nl) Chlorocyphidae, especially the common Dancing Jewel (Platycypha caligata) of tropical eastern Africa, are known for their bright coloration and showy displays. To quote Elliot C.G. Pinhey (1965): "The female rests on a twig in seemingly bored contemplation while the male performs a little aerial dance, backwards and forwards in the arc of a circle, orientated towards the female and dangling the white surfaces of the tibiae below his head like a beard. If competition is keen, however, such formalities are generally omitted and he merely pounces on her without any prelude". In August 1981, Pinhey presented a paper at the international symposium of odonatology in Chur, Switzerland, titled "Platycypha caligata (Selys) and a new lacustrine morph (Odonata: Chlorocyphidae)" (see photograph in Dijkstra et al. 2003). The presentation formed the outcome of his investigation of Platycypha specimens collected on the shore of Lake Malawi, and an intensive correspondence with their collector, John G. M. Wilson. In January 2002, I met both the collector and the collected, which shedded new light on Lake Malawi's Platycypha. Quotes from Pinhey's letters to Wilson in 1980, that the latter has kindly allowed me to reproduce, neatly summarise Pinhey's interpretation of the Malawi specimens. He first mentioned them in a letter dated 2 April: "The species of particular interest, and for which this letter is written is a new Platycypha. [.] Do see if you can find more, including the female, a duller looking girl. [...] Platycypha like fast running streams, often in shade, settling on branches or on rocks. [.] I have long suspected there must [emphasis by Pinhey] be a new species of Platycypha or Chlorocypha in Malawi." Twenty days later, following a reply with ecological details from Wilson, he continued: "The ecology of that Platycypha is most intriguing, inhabiting rocks on lake shore. [.] I must find time to write up this new species. [.] I will hope to name it after its discoverer! If you could possibly pickle a mature male in 75% alcohol immediately on capture it would help in the description." Pinhey elaborated on 6 June: "A lake breeder is quite remarkable [.]. Your colour photos will help in checking colours of the male." On 30 June he apologized: "I am sorry I put you to so much trouble over the reproduction of living colours of your new Platycypha and, particularly, in the great misfortune of losing your close-up lens. I am sorry if this resulted from my persuasion. [...] When I suggested alcohol I had no idea this universal fluid would be so hard to obtain in its preservative form." After receiving the photographs and alcohol material Pinhey altered his opinion, as evidenced by a letter dated 3 July: "The colour slides are excellent but [have not] solved the problem in the expected manner! There were three original male Platycypha [.] Two showed peculiar markings on abdominal segments 4-5 which seemed distinctive but the third was different, rather nearer caligata. That is why I asked for a pickled example (or photos) in order to clarify the markings and to see if there was any overall colour difference. The colour photos show the male to be the same colour as mature caligata and [.] proves that there is really no definite pattern difference from that species. I am still working on other characters, but I am sorry to say they appear to be caligata after all, and at most there may be differences developed from a change in ecological conditions. The unusual habits in themselves will be worth describing apart from any morphological characters there may be. I am sorry to disappoint you (and myself)." Six days later he expanded: "I should have expected staining [.] However, I am developing a possible distinction for the lake populations. Out of 150 male caligata examined from many parts of Africa your nine lake males are invariably smaller than all the rest, except for another male (singleton) which R. C. Wood sent me in August 1961 from the lake shore at Cape Maclear! This seems significant. Moreover their tibial expansions are less than average for other populations. [.] Thus, there does seem reason to believe that at least the ecology has resulted in some [emphasis by Pinhey] difference, particularly in diminishing size. [.] I will [.] continue on a paper outlining the supposition that Platycypha caligata has adapted to both riverine and lacustrine environments, unlike other known African species of the family. This in itself is of much interest. It is unlikely, I suppose, that any freshwater fish show similar tendencies to modify under such changes?" The final question directed at Wilson, a fisheries biologist, is remarkable considering Lake Malawi's fame for its profusion of endemic species of specialized cichlid fish. On 10 December Pinhey concluded: "In August next year I will read my paper on your lacustrine Platycypha to the World's Odonata gathering in Switzerland. Your name will be uppermost in the script." In the proceedings resulting from the paper read, Pinhey (1982) described the Lake Malawi specimens as a form of Platycypha caligata. The Lake Malawi examples are constantly smaller than specimens from throughout the species's range, but differences in coloration were dismissed by Pinhey (1982), who stated: "The [initial] three males seemed at first to have unusual but rather consistent markings [.] Further examination [.] showed that these markings were only post-mortem discoloration changes." During a visit to a rocky islet 2 km off the lake coast on 1 January 2002, I encountered numerous Platycypha specimens. The first impression was of a much smaller and darker insect than typical caligata. Some males had the basal segments darkened, a condition not occurring in caligata, while others had the typical all-blue abdomen. Mature males were found perched near the waterline, whereas females and teneral males were abundant among the bushes that crowned the isle. It appeared that S1-5 become extensively melanised with age, which is not seen in typical riverine P. caligata. Presumably the resulting difference in markings initially lead Pinhey to conclude this was a new species, but he only received additional material and photographs of young specimens. He thus decided the differences were caused by staining, describing the lacustrine Platycypha as a mere form. From the research history illustrated by Pinhey's quotes and his emphasis on colour patterns therein, it may be deduced that he would have regarded the Lake Malawi specimens as a good species if he had known the nature of their coloration. At the Chala crater lake on the Kenya-Tanzania border, P. caligata is similarly small, but does not darken with age (V. Clausnitzer pers. comm.). Molecular studies may prove that Lake Malawi is home to an endemic species of Platycypha, and not just dwarfed specimens of P. caligata as seen at Lake Chala. Dijkstra, K.-D.B., A. Martens & M.J. Parr, 2003. Proceedings of the 1st PHAON Meeting on African Odonata, Gllivare, 26 July 2001, Foreword, African Odonatology: past, present and future. Cimbebasia 18: 161-166. Pinhey, E., 1965. Development of the study of Odonata (Dragonflies) in Central Africa. Proceedings of the Central African Scientific and Medical Congress, Lusaka, Northern Rhodesia, 26-30 August, 1963. Pergamon Press, Oxford 321-331. Pinhey, E., 1982. Platycypha caligata (Selys) and a new lacustrine morph (Odonata: Chlorocyphidae). Advances in Odonatology 1: 213-225.