Speonemadus Jeannel, 1922

Reboleira, Ana Sofa P. S., Fresneda, Javier & Salgado, José Maria, 2017, A new species of Speonemadus from Portugal, with the revision of the escalerai-group (Coleoptera, Leiodidae), European Journal of Taxonomy 261, pp. 1-23 : 3

Genus Speonemadus Jeannel, 1922

Speonemadus escalerai -group; “Gruppo escalerai ” sensu Giachino & Vailati 1993: 205.

Representatives of this group are characterized by a body length between 3.9 to 5.0 mm and have a slightly transverse pronotum ( Figs 6–15 ); the anterior tibia of the males is compressed towards the apical half and has a keel with different shapes on the dorsal edge ( Figs 16–20 ); elytra have a rounded apex in males and a notched one in females. The median lobe of the aedeagus is elongated and bottleshaped in dorsal view ( Figs 21–25 ) and the inner sac lacks a ventral tooth in the apical region of the middle lobe and has two long parallel rows of fine spines and teeth ( Figs 23–24 ).

All species of the group have similar color patterns, the same antennal shape and development of the membranous wings in both sexes, as well as similar genital segments and aedeagi in males, and similar 7th and 8th urosternites and spermatheca of females.

The life-style of this group is mostly subterranean, they are frequently found under stones or in leaf litter in forests and in caves, walking in bat guano or in the subterranean substrate.

Key to the species of the Speonemadus escalerai -group

Note to the key: diversification of the species of the escalerai -group is likely to be recent (see below “Speciation and biogeography”). Therefore, morphological differences are not particularly visible and a combination of characters should be used for species recognition. All species and both sexes of the “ escalerai ” group show a similar coloration, shape of the antenna, development of membranous wings, genital segment in the male aedeagus and 7th and 8th uroventrites, as well as spermatheca of the females. Females have no characters to distinguish between species, which also occurs in other genera of the Leiodidae , e.g., Colon Herbst, 1797. Only females of S. angusticollis can be separated from other species by the shape of the pronotum, being the only one with a bell-shape, as in males. Therefore, in this species group only males provide distinctive characters useful for identification. These characters are identified in all key items and constitute the basis of specific differentiation.

1. Male with a high protibial keel, with the highest point around middle of the tibia ( Figs 16, 18, 20 ) …2

– Male with a lower protibial keel, with the highest point at the basal third of the tibia ( Figs 17, 19 ) …4

2. Protibial keel with sharp vertex and slightly lobed from the margin to the base ( Fig. 20 ); elytra sculpture and pronotum granularity poorly marked; pronotum sexually dimorphic ( Figs 14–15 ) …… ………………………………………………………………………… S. escalerai ( Uhagón, 1898)

– Protibial keel with a slightly sharp vertex and linear margin to the base ( Figs 16, 18 ); elytra sculpture and pronotum with well marked granularity; pronotum not sexually dimorphic ( Figs 6–7, 10–11 ) …3

3. Body size generally small (male length around 4.2 mm); protibial keel with sharp apex and basal part of the protibia with a wide keel ( Fig. 18 ); 8th antennomere around 1.5 × longer than wide and 4th one length different from 5th and 7th antennomeres in both sexes … S. bolivari ( Jeannel, 1922)

– Body size generally larger (mean male length around 4.8 mm); protibial keel with rounded apex and the basal area of the protibia with a wider keel ( Fig. 16 ); 8th antennomere more than 1.4 × longer than wide and 4th antennomere equal or almost equal in length to 5th and 7th antennomeres in both sexes ………………………………………………………………… S. algarvensis sp. nov.

4. Upper margin of protibial keel long, linear medially ( Fig. 17 ); 8th antennomere slightly less than 1.5 × longer than wide, and 4th, 5th and 7th antennomeres of unequal length in both sexes …… ……………………………………………………………………… S. angusticollis ( Kraatz, 1870)

– Upper margin of protibial keel short, curved medially ( Fig. 19 ); 8th antennomere more than 1.5 × longer than wide and 4th, 5th and 7th antennomeres of almost equal length in both sexes …………… …………………………………………………………………………… S. breuili ( Jeannel, 1922)

Figures

Figs 6–15. Speonemadus of the escalerai-group pronotum. 6–7. S. algarvensis sp. nov. (Gruta do Vale Telheiro, Portugal), respectively ♂ and ♀. 8–9. S. angusticollis (Kraatz, 1870) (Rute, Spain) respectively ♂ and ♀. 10–11. S. bolivari (Jeannel, 1922) (Ardales, Spain) respectively ♂ and ♀. 12–13. S. breuili (Jeannel, 1922) (Motillas, Spain) respectively ♂ and ♀. 14–15. S. escalerai (Uhagón, 1898) (Jumilla, Spain) respectively ♂ and ♀. Scale bars = 1 mm.

Figs 16 – 20. Speonemadus of the escalerai - group male protibia. 16. Speonemadus algarvensis sp. nov. (Gruta do Vale Telheiro, Portugal). 17. S. angusticollis (Kraatz, 1870) (Rute, Spain). 18. S. bolivari (Jeannel, 1922) (Ardales, Spain). 19. S. breuili (Jeannel, 1922) (Motillas, Spain). 20. S. escalerai (Uhagón, 1898) (Jumilla, Spain). Scale bar = 0.5 mm.

Figs 21 – 25. Speonemadus of the escalerai - group, aedeagus. 21. Paratype of S. algarvensis sp. nov. (Gruta do Vale Telheiro). 22. S. angusticollis (Kraatz, 1870) (Rute). 23. S. bolivari (Jeannel, 1922) (Ardales). 24. S. breuili (Jeannel, 1922) (Motillas). 25. S. escalerai (Uhagón, 1898) (Jumilla). Scale bar = 0.5 mm.