Dactyleurys minimus Kavanaugh and Rainio, 2016

Kavanaugh, David H. & Rainio, Johanna, 2016, Twenty-six New Species of Predaceous Ground Beetles (Coleoptera: Adephaga: Carabidae) from Ranomafana National Park, Madagascar, Proceedings of the California Academy of Sciences 63 (7), pp. 201-268 : 211-212

Dactyleurys minimus Kavanaugh and Rainio , sp. nov.

Figures 6 , 8A , 9A, 9D

TYPE MATERIAL.— Holotype ( Figs. 6A–B ), a male, in CAS, labeled: “ MADAGASCAR, Ranomafana NP, Talatakely, X at 130 m mark 12.4.2005 ”/ “collected by hand in daytime, F. Ratalata & Johanna Rainio collectors”/ “ HOLOTYPE Dactyleurys minimus Kavanaugh & Rainio sp. n. 2015” [red label].

TYPE LOCALITY.— Madagascar, Fianarantsoa Province, Ranomafana National Park .

DERIVATION OF SPECIES NAME.— The species epithet, minimus , is the Latin adjective meaning smallest, a reference to fact that the known adult male of this species is smaller than males of any of the other known species that we have examined.

RECOGNITION.— Smallest adult known for the genus, SBL = 6.9 mm. The following combination of features identify members of this species as coelostomine pterostichines of the genus Dactyleurys : antennae with antennomere 3 attached symmetrically or nearly symmetrically to antennomere 2; mentum with deep emargination, apex of median mental tooth distinctly posterior to apices of epilobes; elytron with epipleuron interrupted by internal plica subapically; parascutellar stria not evident; basal setiferious puncture situated at base of stria 3; tarsomeres 1 to 4 of all legs with dense pads of setae ventrally; front and middle tarsomeres 1 to 3 smoothly convex dorsally; male front tarsomeres 1 to 4 wide, dilated, not latero- or medioapically toothed; aedeagus of male with right face dorsal in repose, right paramere conchoid, left paramere reduced, short, apically digitiform. Members of D. minimus ( Fig. 6A ) differ from those of D. anomalus in the following features: smaller size (SBL = 6.9 mm compared with 7.7–9. 4 mm in D. anomalus ); pronotum ( Fig. 8A ) relatively narrower, widest at middle (relatively wider ( Fig. 8C ) and clearly widest anterior to middle in D. anomalus ); elytra faintly but evidently iridescence and elytral microsculpture markedly transverse with sculpticells great than 2.5 times as wide as long (elytra not iridescent and elytral microsculpture moderately transverse with sculpticells less than 2.5 times as wide as long in D. anomalus ); and median lobe of male genitalia ( Fig. 9A ) with shaft abruptly bent ventrally in apical fourth with apex nearly straight in lateral aspect (shaft nearly straight ventrally ( Fig. 8C ) in apical fourth with apex slightly recurved dorsally in D. anomalus ), apex narrowly rounded in dorsal aspect ( Fig. 9D ) (more broadly rounded ( Fig. 9F ) in D. anomalus ). Members of D. minimus differ from those of the other new species, Dactyleurys ranomafanae , in the following features: smaller size (SBL = 7.7–8. 3 mm in D. ranomafanae ); pronotum ( Fig. 8A ) relatively narrower and with evenly rounded lateral margin (slightly wider ( Fig. 8B ) and with lateral margin slightly straighter in basal one-third in D. ranomafanae ); and median lobe of male genitalia ( Fig. 9A ) with apex nearly straight in lateral aspect (apex slightly recurved dorsally ( Fig. 9C ) in D. ranomafanae ), apical part of shaft ( Fig. 9D ) slightly deflected right in dorsal aspect (apical part of shaft ( Fig. 9E ) straight in D. ranomafanae ).

GEOGRAPHICAL DISTRIBUTION.— At present, known only from the type locality.

HABITAT DISTRIBUTION.— The unique holotype was collected by hand in daytime in secondary montane rain forest in the Talatakely area, at an elevation of 900 m, at the 130 meter mark along Trail “X”. Vegetation in that area consisted of bamboo, small young trees and some larger trees with diameters at breast-height (DBH) of 20–30 cm. Tree trunks and branches were heavily laden with epiphytes and lianas.

Figures

FIGURE 6. Digital images of holotype male of Dactyleurys minimus Kavanaugh & Rainio sp. nov. A. Habitus, dorsal aspect; B. Labels. Scale line = 1.0 mm.

FIGURE 8. Digital images of pronota of Dactyleurys spp., dorsal aspect. A. Holotype of D. minimus Kavanaugh & Rainio sp. nov.; B. Holotype of D. ranomafanae Kavanaugh & Rainio sp. nov.; C. D. anomalus Tschitschérine. Scale lines = 1.0 mm

FIGURE 9. Digital images of aedeagus of male genitalia of Dactyleurys spp. A–C. left lateral aspect; D–F. dorsal aspect. A, D. Holotype of D. minimus Kavanaugh & Rainio sp. nov.; B, E. Holotype of D. ranomafanae Kavanaugh & Rainio sp. nov.; C, F. D. anomalus Tschitschérine. Scale lines = 0.5 mm.