Ptenidium (Gillmeisterium) lambdai, Darby, Michael, 2014

Darby, Michael, 2014, Studies of Madagascan Ptiliidae (Coleoptera) 2: The genus Ptenidium including three new species, Zootaxa 3793 (3), pp. 350-360 : 358

Ptenidium (Gillmeisterium) lambdai sp. n.

( Figs. 2 , 5, 10, 11, 15, 18, 21, 25, 26, 30, 32, 34)

Habitus Fig. 2 . Length 0.77–0.80 mm. Colour reddish brown, antennae and legs yellow. Antennae with very short, almost triangular antennomere 3. Head with +/- 8 yellow setae symmetrically arranged in anterior half. Mentum with distinctly narrowed base and projecting bulbous sides with flattish shoulders Fig. 18 . Width across eyes 0.26–0.27 mm. Pronotum length 0.21–0.23 mm, width 0.36 mm, with scattered very short pubescence, lateral margins with distinct sinuation by median fovea bearing a longer seta; four basal foveae of approximately equal size each bearing a longer seta. Scutellum base with two longitudinal excavations giving the impression of forming a central keel or four foveae depending on the light source Figs 10,11. Elytra length 0.46–0.50 mm, width 0.39–0.42 mm, humeri with a short narrow keel projecting backwards, scattered very shallow foveae tending to form rows, and patches of dense pubescence on the posterior underside Fig.39 . Proventral process with rounded sides, narrowed before base, central raised portion narrow and almost parallel sided; lateral arms of meso/ metaventral suture with indentations near coxae. Pygidium with 6–8 teeth Fig. 34 .

Female: Spermatheca Figs. 25, 26 .

Male: Aedeagus Fig. 30 .

Etymology. I am pleased to name this species after Lambda Photometrics the supplier of the Phenom SEM in the UK whose staff, particularly Tom Lloyd, have been unstinting in their help and advice to me.

Remarks. The smallest of the three species immediately distinguishable by its stubby, rounded appearance and the short, almost triangular 3rd antennomere.

Type data: Holotype: ♀, Ranomafana NP, S.21˚15’ E.47˚25’, 970–990m, 13–15.xi.2010, P. Banar ( BMNH). All the following records are by sifting and Winkler Apparatus extraction from the Ranomafana National Park. 39 exs, S.21˚14’51” E.47˚24’13”, 1079m, 16–18.xi.2010, P. Banar ( BMNH); 10 exs, S.21˚15’ E.47˚25’, 970–990m, 13–15.xi.2010, P. Banar ( BMNH); 1 ex, by stream close to main entrance, 17.xi.2010, P. Banar ( BMNH); 1 ex, RNF/12/2011, S.21˚14’51.3” E.47˚24’09.1”, 1118m, 15.iv.2011, P. Banar & Raveloson ( BMNH); 13 exs, RNF/16/ 2011, S.21˚14’57.9” E.47˚24’22.9”, 1138m, 16.iv.2011, L.S.Rahanitriniaina & R. Raveloson ( BMNH); 1 ex, RNF/ 06/2011, litter in ravine along road, S.21˚14’51.8” E.47˚24’12.1”, 1065m, P. Banar ( BMNH); 2 exs, Vatoharanana, litter, S.21˚15’29.7” E.47˚25’30.3”, 1126m, 5.x.2012, L.S.Rahanitriniaina ( BMNH).

Figures

FIGURES 1 – 3. Ptenidium spp. habitus. 1, P. azafady; 2, P. lambdai; 3, P. tanalai. 4 – 6. Lateral border of the pronotum. 4, P. azafady x 985; 5, P. lambdai x 1180; 6, P. tanalai x 935. 7 – 11. Scutellum. 7, P. reitteri x 850; 8, P. pusillum x 600; 9, P. azafady x 555; 10 – 11, P. lambdai x 1120.

FIGURES 17 – 22. 17 – 19. Ptenidium spp. mentum. 17, P. azafady x 1160; 18, P. lambdai x 1560; 19, P. tanalai x 1600. 20 – 22. Ptenidium spp. antennomeres 3 – 11. 20, P. azafady; 21, P. lambdai; 23, P. tanalai.

FIGURES 36 – 39. Ptenidium tanalai. 36, abdominal tergites showing spines on plates around wing folding spicule patches x 1560; 37, abdominal ventrites showing scalloped edges x 1500; 38, meso / metaventral suture showing wavy edge. x 715; 39, hairs on the underside of the posterior margin of the elytra x 1920.

FIGURES 29 – 35. 29 – 31. Ptenidium spp. aedeagus. 29, P. azafady; 30, P. lambdai; 31, P. tanalai. 32. Ptenidium lambdai male 7 th ventrite. 33 – 35. Ptenidium spp. pygidium teeth. 33, P. azafady x 1240; 34, P. lambdai x 1400; 35, P. tanalai x 2000.

FIGURES 23 – 28. Ptenidium spp. spermatheca. 23 – 24, P. azafady; 25 – 26, P. lambdai; 27 – 28, P. tanalai (28 A viewed from a little above and 28 B a little below).