Lamellothyrea isimangaliso, Perissinotto, Renzo, 2017

Perissinotto, Renzo, 2017, Description of a new species of Lamellothyrea Krikken (Coleoptera, Scarabaeidae, Cetoniinae) from the iSimangaliso Wetland Park, KwaZulu-Natal (South Africa), ZooKeys 688, pp. 35-48 : 36-43

Lamellothyrea isimangaliso sp. n.

Diagnosis.

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.

Description of holotype male

(Figs 1B, 2B, 3 C–D, 4). Size. Length 20.3; width 11.0 mm.

Body. Dark green to purple, with blackish maculation on elytra and residual tomentum on pronotal sides and elytral surface (Figs 1B, 2B, 4); velutinous, with remarkable sheen when exposed to direct light (Fig. 4).

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. 2B); frons with one major transverse round lamina, one minor frontal lamina and one longitudinal ridge extending to posterior end of vertex; numerous long, yellow to orange setae emerging from all cavities; frontal cavity forming secondary, shorter horns at lateral margins; entire surface covered in coarse, round punctures or geminate striae, except on clypeal ridges and supra-ocular tubercle (Figs 1B, 2B); antennal clubs dark brown, of normal cetonid length, of approximately the same length of flagellum; pedicel dark brown to black, flagellum brown, both bearing scattered but long, erected yellow setae.

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 1B, 4).

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. 1B).

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 1B, 4).

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. 1B).

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. 3C); dorsal lobes narrower than ventral lobes and sharply constricted at mid length, then expanded again at apex; apex broad with sinuations and small sutural projections at centre (Fig. 3 C–D).

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.

Description of female.

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. 3B).

Distribution.

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.

Conservation status.

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 ( Porter 2013).

Biology.

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 ( Combrink and Kyle 2006).

Remarks.

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.

Type material examined.

Holotype (♂): South Africa, KZN, St Lucia, 19-20 Feb 2000, R Perissinotto & L Clennell (TMSA). Paratypes: 2♂♂, as above (PCPC); 1 ♀, as above, but 13 Jan 2001; 1♂, as above, but 17 Feb 2001 (PCPC); 1♀, as above, but 12-13 Feb 2000; 1♀, as above, but 01 Jan 1999 (PCPC); 2♂♂, as above, but 28 Feb 99 (PCPC); 1♂, as above, but 30 Oct 1999; 4♂♂, 4♀♀, as above, but 20-23 Mar 2004 (ISAM, DMSA); 1♂, but False Bay, 4 Apr 2012 (PCPC); 1♂, KZN, iSimangaliso, Dec 2002, X. Combrink leg (PCPC); 1♂, KZN, Kosi Mouth, 21/10/2003, R Kyle leg (PCPC); 1♂, Natal, Mapelane, 12/93, I.R. Willem (PCPC); 14♂♂ + 5♀♀, South Africa KwaZulu-Natal, 6 km N of St. Lucia Bay, S27°38'16", E32°26'24" 20 m a.s.l., 22-30 Dec 1990, P. Stobbia leg. (PCBM); 12♂♂ + 7♀♀, South Africa, KwaZulu-Natal, St. Lucia Bay S28°22'13", E32°24'50" 23 m a.s.l., 12 Dec 1994, A.P. Marais leg. (PCBM); 1 ♀, South Africa KZN, Sodwana Bay 27.33S, 32.40E 30 m, 1987/03/05, Reavell PE leg., Coastal dune forest, Feeding on fruit (unspecified) (SANC, COLS16846); 8♂♂ + 6♀♀, South Africa KZN, near Lake Nhlabane, 25 km NE of Richards Bay 28.38S 32.16E, 1991/02/03, Vogt M leg., Coastal dune forest, Hanging fermenting fruit bait trap, Specimen from University of Pretoria research programme into post-mining dune rehabilitation at Richards Bay Minerals, In rehabilitating dune forest 12 years post mining (SANC, COLS16847); 1♀, South Africa KZN, near Lake Nhlabane, 25 km NE of Richards Bay 28.38S, 32.16E, 1992/03/16 to 1992/03/20; Vogt M leg., Coastal dune forest, Hanging fermenting fruit bait trap, Specimen from University of Pretoria research programme into post-mining dune rehabilitation at Richards Bay Minerals (SANC, COLS16848); 1♂, South Africa KZN, Sodwana Bay 27.33S, 32.40E, 1988/01/05 to 1988-01-06, E Holm E & E Marais leg., Hanging fermenting fruit bait trap (SANC, COLS16849); 10 ind., South Africa, Zululand Natal, Sodwana Bay 5 km S, 27.35S, 32.39E, 23/11/1992, Endrody-Younga E-Y: 2845, Ground traps, 4 days, with banana bait (TMSA, CPH6477); 14 ind., South Africa, Zululand Natal, Sodwana Bay 5km S, 27.35S, 32.39E, 23/11/1992, Endrödy-Younga leg. E-Y: 2846, Hanging fruit traps (TMSA, CPH6478); 1 ind., South Africa, Zululand Natal, Sodwana Bay 5km S, 27.35S, 32.39E, 23/11/1992, Endrödy-Younga leg. E-Y: 2847, Grass netting (TMSA, CPH6479); 2 ind., South Africa, Natal, Sodwana Bay 27.32S, 32.42E, 16/1/1992, M. Vogt & E. Holm leg. (TMSA, CPH6480); 1 ind., South Africa, Natal, Sodwana Bay, 4 –12– 1988, HP Terblanche leg., Waterbessie (TMSA, CPH6481); 1 ind., South Africa, Zululand Natal, Sodwana Bay, 28/2/1982 (TMSA, CPH6482); 1 ind., South Africa, Natal, Sodwana Bay Nat. Res., 27.32S 32.4E, 1/1988, O. Bourquin leg., Baited forest trap (TMSA, CPH6483); 1 ind., South Africa, Natal, Sodwana Bay Nat. Park Cmpgrd., 9-13/11/1986, Evans, d’Hotman & Nel leg. (TMSA, CPH6484); 1 ind., South Africa, Natal, Cape Vidal Park Cmpgrd., 28.07S, 32.33E, 13-15/11/1986, Evans, d’Hotman & Nel leg. (TMSA, CPH6485); 1 ind., South Africa, Natal, Cape Vidal, St. Lucia Nat. Res., 28.08S 32.33E, 1-4/1/1988, E. Holm & E. Marais leg., Bait traps (TMSA, CPH6486); 2 ind., South Africa, KZN, St Lucia, 22 Mar 2004, R Perissinotto & L Clennell (DMSA, COL35760, COL35760); 1 ind., as above but 26 Oct 2004 (DMSA, COL35762); 3 ind., as above but 1 Oct 2008 (DMSA, COL35763, COL35764, COL35765); 2♂♂ + 1♀, RSA KwaZulu-Natal, St Lucia, 20-22/03/2004, Perissinotto & Clennell (TGPC); 2♂♂ + 2♀♀, RSA N. Natal, Sodwana Bay, 03/1994 (TGPC); 3♂♂ + 2♀♀, South Africa KZN, St Lucia, 20-22 Mar 2004, R Perissinotto & L Clennell (CDPC); 3 ind., South Africa, KwaZulu-Natal, St. Lucia -28.37.500S, 32.42694E, 20-22/3/1904 (most likely 2004), (ISAM, COL-A059118); 3♂♂ + 2♀♀, S-Africa Natal, Sta Lucia, 1-91, Ex collection Dr. Vincent Allard received from Christophe Allard 21.II.2015 (GBPC); 1♂, R.S.A. Zululand, Sodwana Bay, II-1987. P. Stobbia, Ex collection Dr. Vincent Allard received from Christophe Allard 21.II.2015 (GBPC); 1♀, R.S.A. Zululand, Sodwana Bay, 7 –XI– 1987. P. Stobbia, Ex collection Dr. Vincent Allard received from Christophe Allard 21.II.2015 (GBPC); 1♂ + 1♀, RSA Natal, St. Lucia, 1.1991, coll. V. Allard (GBPC); 1♂ + 1♀, No data, Ex collection Dr. Vincent Allard received from Christophe Allard 21.II.2015 (GBPC); 1♀, RSA Natal, St. Lucia, 3.1992, coll. Owen (GBPC); 1♂, South Africa,, KZN, St Lucia 31 Oct 2008, R. Perissinotto & L. Clennell leg. (SRPC); 1♀, 11 –XII– 2008, South Africa, KZN, 11 Dec 2008, St Lucia R. Perissinotto & L. Clennell leg. (SRPC).