Semiclivina Kult, 1947

Dostal, Alexander, 2011, Taxonomic remarks about Semiclivina (Kult, 1947) new status, with description of Uroclivina subgen. n., and of two new species from South America (Coleoptera, Carabidae, Scaritinae, Clivinini), ZooKeys 132, pp. 33-50 : 34-35

Genus Semiclivina Kult, 1947 stat. n.

Clivina Subgenus Semiclivina Kult 1947: 31-32; Reichardt 1977: 391; Nichols 1988a: 154; 1988b: 91; Ball 2001: 136; Lorenz 2005: 145; Baehr 2008: 23; Bousquet 2009: 41.

Type Species.

Clivina dentipes Dejaen, 1825, by original designation: Kult 1947: 31.

The genus Semiclivina (Kult, 1947) is readily recognized by the sculptured band of the proepisternum, extended more or less parallel to the proepisternal margin in the basal part of the proepisternum, curved inward in the anterior part, ended at the anterior end of the proepisternal-prosternal suture (Fig. 1). This structure was differently interpreted by diverse authors ( Bousquet 2009: 38) as furrow, ridge or carina or elongate striole ( Baehr 2008: 23). In fact it is a slightly elevated band like structure consisting of very fine, regular transverse ridges. This sculptured band ( Bousquet 2009: 38) is part of a stridulation organ in the sense of a pars stridens, whereas the corresponding plectrum is a fine, sharp longitudinal ridge, just above the distal part of the lower inner edge of the profemur (Fig. 2). In some species the outer edge of the profemur is produced to a remarkable denticle, but this structure does not interact with the stridulation organ in any way. The function of this stridulation organ has not been observed so far.

This organ is not unique within the Tribe Clivinini : exactly the same structures (the stridulation ridge on proepisterna and the ridge on the distal part of the inner edge of the profemur) together with other features separates the ardistomine genus Ardistomis Putzeys, 1846 from Semiardistomis Kult, 1950, but it is unique within Clivina (sensu lato), forming a very isolated, distinct group, restricted to the western hemisphere and to a single species from Australia (New South Wales) described by Baehr 2008: 23-25. Within the tribe Clivinini no other genera than Ardistomis Putzeys, 1846 and Semiclivina (Kult, 1947) carry a stridulation organ on the proepisternum. Beside this, Semiclivina is characterized by a distal spine-like projection at the outer end of the mesotibia, which is small in some taxa, but clearly identifiable by the apical seta excentrically inserted, in contradiction to a tubercle, which carries the seta at the top of the tubercle (see also Ball 2001: 136, 140; Bousquet 2009: 41, 43); usually five setae in elytral interval 3 (including preapical puncture); elytral striae 1 to 5 free at base (between humeral channel and suture, the basal keel of some species and the flat tubercles at the end of intervals 2 to 5 do not limit this definition); profemur with a sometimes small dentiform projection at the outer edge toward apex; anal ventrite (abdominal sternum VII) with two marginal punctures at each side relatively close together. The species included in Semiclivina are listed in Bousquet (2009: 39-41), where the assignment of some species remains uncertain. It is most likely, that species not included in the subgen. n. Uroclivina comprise a more or less heterogeneous group which form a probably paraphyletic group, defined as Semiclivina (s. str.). This subgenus will be the objective of further investigations in the future.