Research Article |
Corresponding author: Renzo Perissinotto ( renzo.perissinotto@nmmu.ac.za ) Academic editor: Andrey Frolov
© 2017 Renzo Perissinotto.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Perissinotto R (2017) Description of a new species of Lamellothyrea Krikken (Coleoptera, Scarabaeidae, Cetoniinae) from the iSimangaliso Wetland Park, KwaZulu-Natal (South Africa). ZooKeys 688: 35-48. https://doi.org/10.3897/zookeys.688.13632
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Recent data and material obtained from northern KwaZulu-Natal (South Africa) and Maputo Bay (Mozambique) have provided support for the description of a new species of the genus Lamellothyrea Krikken, 1980. The genus previously included only one species, L. descarpentriesi, with uncertain and poorly defined type locality, i.e. “Transvaal”. It is now evident that two different species are actually involved, L. descarpentriesi with currently known distribution limited to the coastal area north of Maputo, and L. isimangaliso sp. n. with a known distribution range virtually restricted to the iSimangaliso Wetland Park, in north-eastern KwaZulu-Natal. The two species appear to be separated by a substantial discontinuity in southern Mozambique and can be easily separated on the basis of their clypeal structure, extent of white dorsal tomentum and shape of aedeagal parameres. Both species appear to be restricted to the coastal belt, with L. isimangaliso sp. n. occupying almost exclusively dune forest habitats. In this species, adult activity depends on rainfall and shows two peaks, one at the onset of summer and the second in autumn.
Lamellothyrea , Cetoniinae , new species, South Africa, Mozambique
The genus Lamellothyrea was described by Krikken in 1980 on the basis of a single male specimen reportedly from the “Transvaal” in South Africa. It has until now included only one species, L. descarpentriesi, with a reported distribution restricted to the coastal area of northern KwaZulu-Natal (KZN) and a vague type locality. It has now emerged, however, that two specimens recently collected along the Mozambique coast, north of Maputo Bay represent a different species to that occurring in northern KZN. An analysis of these specimens has revealed that they exhibit remarkable similarity with the holotype and conform well to the original description of
On the other hand, the numerous material now available for the KwaZulu-Natal population shows that this is distinct in many respects from the Mozambique and holotype specimens. This distinction appears to be best expressed at the level of the clypeal armour and in the parameres of the male genitalia. Thus, two separate species are involved, with the KwaZulu-Natal species here described as L. isimangaliso sp. n.
Substantial ecological data and observations have also become available from the recent studies undertaken in the iSimangaliso Wetland Park in KwaZulu-Natal, within its “Rare, Threatened and Endemic Species Project” (
Since the original description of Lamellothyrea (
For the description of morphological characters, the terminology used by
BMPC Jonathan Ball and Andre Marais Private Collection, Cape Town, South Africa;
CDPC Cyril Di Gennaro Private Collection, Arcueil, France;
DMPC Daniel Moore Private Collection, Oro Valley, USA;
EPPC Ernest Pringle Private Collection, Bedford, South Africa;
GBPC Gerhard Beinhundner Private Collection, Euerbach, Germany;
PCPC Renzo Perissinotto and Lynette Clennell Private Collection, Port Elizabeth, South Africa;
SRPC Sébastien Rojkoff Private Collection, Lyon, France;
TGPC Thierry Garnier Private Collection, Montpellier, France;
Data on distribution and period of adult activity were also obtained from the literature (
Lamellothyrea
descarpentriesi
Krikken, 1980: 185–187;
Holotype (♂): Transvaal (
While a detailed description of the holotype male of this species, complete with quality drawings, is provided in
The two species of Lamellothyrea can easily be separated on the basis of their key differences at the level of the clypeal armour, parameres of the male genitalia and the general body colour and ornamentation. In particular, both clypeal horns and longitudinal blade are more pronounced and developed in L. isimangaliso sp. n. than in L. descarpentriesi. The clypeal horns of L. isimangaliso are narrower but projected further forward than those of L. descarpentriesi; they are also sharper and form a distinct point at the internal apex. The total body length of L. descarpentriesi appears to be slightly shorter than that of L. isimangaliso and the tomentose maculation on the dorsal surface is much more developed in the former than in the latter species. Lamellothyrea descarpentriesi is also more uniform in its background colouration, which is consistently dark green, while a purple sheen and even brown-green dominance generally prevails in L. isimangaliso. Finally, the aedeagal parameres are slightly longer in L. isimangaliso, with their dorsal lobes narrowing substantially in the middle and then forming a sinuate apex with a visible protuberance on each side. In L. descarpentriesi, the dorsal lobes are more compact and virtually lack both central constriction and apical protuberances.
(Figs
Body. Dark green to purple, with blackish maculation on elytra and residual tomentum on pronotal sides and elytral surface (Figs
Head. Black to dark green towards vertex; clypeus deeply concave and sharply upturned at anterior margin, where two symmetrical lateral horns with external indentation project forward (Fig.
Pronotum. Octagonal with angles smoothly rounded; lateral margins carinate and exhibiting white cretaceous band often interrupted, particularly near base and apex; posterior margin trisinuate with pre-scutellar arch marked; purple to brown, with widespread iridescence and five longitudinal black to dark-green bands (narrow one at center and two broader ones on each side); matt with dense crescent to semi-crescent sculpture, except on pre-scutellar arch; short, scattered yellow setae present throughout surface, longer at margins but absent on pre-scutellar arch (Figs
Scutellum. Purple to brown and even black at base; generally smooth, with few scattered punctures and setae at margins only; broadly triangular with sharp apex and without lateral grooves (Fig.
Elytron. With moderately elevated sutural, discal, humeral and lateral costae; colour varying from purple to brown, with dark spots and bands particularly developed on apical half, on lateral declivity and above humeral callus; residual tomentose marking noticeable only along lateral declivity; both humeral and apical calluses pronounced; apical margin smoothly rounded, bearing a short proximal spine; crescent to horseshoe punctures on all interstrial surfaces, with very short yellow setae scattered throughout but becoming longer on lateral and apical declivities (Figs
Pygidium. Triangular and remarkably convex; black to dark green, without any tomentum; with dense layered to wrinkled sculpture throughout and short yellow setae at centre, becoming much longer on apico-lateral margins.
Legs. Slender and elongate, with apical tarsal segments hypertrophic; protibia effectively bidentate, with third tooth obsolete and well-developed longitudinal grooves, with sparse short yellow setae, becoming longer and denser on inner margin; meso- and metatibia with longer and denser yellow setae, with striolate surfaces and mid spine on outer carina, distal margin bi- and tridentate respectively; spurs slender and sharply pointed, twice as long in metatibia than in mesotibia (Fig.
Ventral surface. Shiny dark brown to green; exhibiting small and sparse crescent sculpture throughout surface; with long and dense yellow setae throughout surface, except on metasternum, metafemora and abdominal sternites; mesometasternal lobe very round and broadly expanded anteriorly; abdominal sternites with visible concavity at centre.
Aedeagus. Parameres with blunt apex in both lateral and dorsal view (Fig.
Derivatio nominis. The name L. isimangaliso sp. n. reflects its known distribution range, which, with the exception of the southern locality of Lake Nhlabane, falls entirely within the iSimangaliso Wetland Park, South Africa’s first UNESCO World Heritage Site.
There is little sexual dimorphism in this species. The main difference lies in the female exhibiting a tridentate and more enlarged protibia than the male. The general body shape of the female also appears more globose than that of the male, particularly at the level of the abdominal sternites, which bulge out quite significantly to impart a convex shape. The length of the antennal clubs is slightly shorter than in the male. Finally, the female metatibial spurs are more blunt, concave and laterally expanded, assuming the shape of a typical fossorial organ used to burrow into the dune sand (Fig.
The species appears to be virtually restricted to the coastal dune forest of the iSimangaliso Wetland Park. The only known record outside the Park is from Lake Nhlabane, which is located about 10 km southeast of its southern boundary.
Although there are indications that coastal dune mining maybe negatively impacting the population of L. isimangaliso at the southernmost end of its distribution range, there are currently no threats to the species, as its habitat within the iSimangaliso Wetland Park is entirely under statutory protection. The Park was proclaimed as South Africa’s first UNESCO World Heritage Site in 1999, and is particularly recognised for its exceptional biodiversity and as a center of endemism (
Although its larval stages remain unknown, L. isimangaliso is a typical coastal forest dweller. The period of adult activity mirrors the pattern of rainfall in the region, with a bimodal distribution and peaks in November-December and February-March. Both sexes have been repeatedly observed feeding on flowers and fruits of dune waterberry trees, Sizygium cordatum and have occasionally been trapped using aerial devices baited with fermenting fruits (
Within the type series, the size ranges as follows: ♂ length 20.1–21.4 mm, width 11.0–11.4 mm (n = 21); ♀ length 21.2–21.8 mm, width 11.3–12.0 mm (n = 11).
There is substantial variability in the background colouration of the numerous specimens of L. isimangaliso sp. n. examined, ranging from light-brown to purple and dark-green. The velutinous purple sheen is, however, the most dominant chromatic form in both sexes. The residual tomentose spots on the elytral and pronotal margins are always poorly noticeable and can virtually disappear completely in some specimens. The vittate pronotum seems to be a consistent feature, but the longitudinal bands range in colour from black to dark-green and even brown. The pygidial background colour is invariably dark green, but occasionally it exhibits residual tomentum near the basal margin.
Holotype (♂): South Africa, KZN, St Lucia, 19–20 Feb 2000, R Perissinotto & L Clennell (
The relatively short gap in distribution between the two species, i.e. about 130 km, is surprising to some extent, but actually involves a major climatic and vegetation transition from wetter coastal forests in the south to the drier swamp forests and Indian Ocean coastal belt vegetation in the north-east (
While the only two dated records available for L. descarpentriesi show that this species is active at least from late winter (August) to early spring (October), in northern KZN adults of L. isimangaliso appear to be especially active during the rainy months, from October through May. In accordance with what was previously reported by
Unfortunately, virtually nothing is yet known about the biology/ecology of L. descarpentriesi, as no other information is provided on the data labels that accompany the few specimens that are currently known. On the other hand, L. isimangaliso shows a preference for dense forest clumps and the immediate outskirts of forests. It has mostly been collected using fruit-baited traps containing either fermenting banana, pineapple, or a fruit-wine-sugar mixture. It has also been observed and captured hovering above, and feeding on, fruits and flowers of Syzigium cordatum (waterberry tree) and on sap of Ziziphus sp. (cf. specimen data labels). This species has so far only been observed in a narrow coastal forest belt, and appears to avoid moving further inland. This restricted distribution suggests that it is linked to a very specific microclimate and possibly able to tolerate only a narrow range of environmental variability. In this context, the protection afforded by the special status of the iSimangaliso Wetland Park, as an UNESCO World Heritage Site, is crucial towards the survival of this species in the long term.
The iSimangaliso Wetland Park Authority and Ezemvelo KZN Wildlife are gratefully acknowledged for providing logistical assistance and permits for this study. Funding for the project was provided through productivity grants awarded by the Nelson Mandela Metropolitan University (Port Elizabeth, South Africa). Thanks to Lynette Clennell for taking all photos included in the manuscript. Jonathan Ball and Andre Marais (Cape Town) are thanked for providing the male specimen of L. descarpentriesi from Marracuene and other valuable data and information used in this study. The following curators and collectors (listed in alphabetic order) are also thanked for submitting specimens for analysis and/or invaluable data towards the completion of this work: Gerhard Beinhundner (Euerbach, Germany); Cyril Di Gennaro (Arcueil, France); Thierry Garnier (Montpellier, France); Aisha Mayekiso (