Bousquet, Bousquet, 2009

Bousquet, Yves, 2009, Rediscovery of Clivina morio Dejean with the description of Leucocara, a new subgenus of Clivina Latreille (Coleoptera, Carabidae, Clivinini), ZooKeys 25 (25), pp. 37-48 : 43-47

Subgenus Leucocara Bousquet , subgen. n.

urn:lsid:zoobank.org:act:05AD95B8-1397-46E1-89C5-1A9CC5CD819F

Type species: Clivina americana Dejean, 1831 (here designated)

Etymology. From the Greek leukos (white) and kara (head). Th e name is proposed in memory of Donald Robert Whitehead [1938–1990] who had an interest in Clivina and the Clivinini in general. His family name has been used in the past to denote a scaritine genus ( Whiteheadiana Perrault ) and a curculionid genus ( Whiteheadia Alonso-Zarazaga & Lyal ).

Recognition. Members of this subgenus differ from those of other Nearctic Clivina by the presence of a small, apically truncate preapical protuberance on the mesotibia with its seta inserted apically.

Description. Head. Supraantennal lobes not prominent, distinctly posteriad anterior edge of clypeus. Lateral wings of clypeus isolated from median portion by extension of frontal impressions; median portion of clypeus coarsely beaded. Labrum with seven long setae. Mandible with scrobe depressed, not distinctly laterad, evident from dorsal aspect. Labial mentum with prominent U-shaped ridge; glossal sclerite acutely carinate medially, carina not sinuate; apex of glossal sclerite with one long seta medially; paramedian pit organs widely separate medially. Prothorax. Pronotum with lateral bead extended to basal edge; posteriolateral angle delimited, angulate; side without accessory dentiform projection posteriad posterior angle. Proepisternum without sculptured band. Elytra. Lateral gutter clearly extended inside humerus, humeral portion clearly delineated; umbilical setae not set up in ringed depressions. Interval 3 with three or four discal setae; second discal seta not adjoining stria 3 though close to it in some individuals, in most individuals rela-

Figures 2–3. Mesotibia. 2 Clivina americana (ventral view) 3 Clivina fossor (dorsal view). Scale bars = 0.2 mm

tively close to stria 2 or in middle of interval 3; interval 8 carinate toward apex and briefly toward base. Striae 4 and 5 joined at base. Legs. Profemur ventrally with a small dentiform projection toward apex. Mesotibia with preapical apophysis small, seta apicad (Fig. 2). Abdomen. Sternum III with coxal lines medially; sternum VII with preapical setae on each side proximate, distance between them less than that between medial setae.

Phylogenetic status. A small, truncate protuberance of the mesotibia (Fig. 2) is probably the plesiomorphic state among the Clivinini and does not support the idea that Leucocara is monophyletic. In fact, the genus Clivina is a large, inadequately defined complex and consequently the structural characters are difficult to polarize. Therefore, I am unable to offer any morphological evidence that Leucocara is natural. However, the species, at least those I have seen (see “Species included” section), are extremely similar to one another in external features and this is sufficient grounds for recognition of the group until it is subjected to phylogenetic analysis.

Geographical distribution. The known range of Leucocara includes the Western Hemisphere Nearctic Region, and the Eastern Hemisphere Palaearctic, Oriental, and Afrotropical Regions.

Species included. Names of species belonging to Leucocara are listed in Table 2. Taxonomic remarks about selected taxa are as follows.

Th e Western Hemisphere species

Based on Bousquet and Larochelle (1993: 103), the americana group contains five species in North America: C. americana Dejean , C. analis Putzeys , C. californica Van Dyke , C. morula LeConte , and C. rufa LeConte. However , in his unpublished thesis, Nichols (1988: 148) revalidated C. acuducta Haldeman (previously in synonymy with C. americana ), synonymized C. morula with C. americana [new synonymy] and reinstated C. analis as a synonym of C. americana . Th is leaves the americana group with five valid North American species: acuducta , americana , californica , morio , and rufa . All these species, except C. californica which is known only from the type locality in Lake County, California, are found in the eastern part of the continent. Th e group, as far as known, as no representatives in the Neotropical Region.

Clivina morio was previously known from the holotype only ( Bousquet 2006: 25 ). I have now seen three additional specimens. Two were collected at UV light in Louisiana, 4.2 mi. NE of Abita Springs, St. Tammany Parish, by V. Brou, one on May 30, 2001, the other one on June 2, 1988. Th ese specimens are in the Louisiana State Arthropod collection, Baton Rouge. Th e third specimen is in the Canadian National Collection of Insects, Ottawa, and was collected at 12 mi. SW of Lufkin, Trinity Co., Texas on 22 April 1976 by A. Smetana. Th e species can be distinguished from the other eastern North American species of Leucocara by its size and shorter metepisternum. The four specimens studied of C. morio range between 7.0 and 8.5 mm in size while the largest specimen seen of the other species reach only 6.4 mm. Th e ratio length of metasternum, measured at the shortest distance between the meso- and metacoxa, and length of metacoxa measured in the same line as the metasternum is 0.9–1.0 in C. morio while it is 1.2–1.5 in the other eastern species. Th e strial punctures in C. morio are also larger, those on the anterior half of the elytra being larger than the depression around the anterior discal seta while in the other species the strial punctures are subequal or smaller than the depression around the anterior discal seta.

Th e Eastern Hemisphere taxa

Despite having seen but few species, there is little doubt that Leucocara is well represented in the Eastern Hemisphere. The tranquebarica group, of which I have seen three species only, includes 15 species ( Kult 1951: 18–24) and the natalensis group, of which I have studied but one species, consists of 43 species in Africa ( Kult 1959: 179–206). One Asian species, C. zebi Kult , reaches the Australian Region where it is found in New Guinea, New Britain, and Australia ( Darlington 1962: 362). Th e three Afrotropical species of the rugiceps group probably also belong to Leucocara . According to Kult (1959: 176), adults of the rugiceps group have also a small mesotibial protuberance but contrary to those of the natalensis -group have only one pair of preapical setae (instead of two) on abdominal sternum VII. On the other hand, the species of the attenuata group of the Oriental region (five species), despite having a small mesotibial protuberance, have the preapical setae equidistant on abdominal sternum VII ( Kult 1951: 18), no discal setae on interval 3 ( Kult 1951: 18), the labrum with six setae ( Andrewes 1929: 353), and the glossal sclerite with two apical setae (checked on C. striata Putzeys only). In my opinion, this group of species is probably not closely related to Leucocara and would need a new subgeneric name.

All remaining groups of species previously included in the subgenus Reichardtula have a long, apically acuminate mesotibial protuberance (Fig. 3). As now restricted, this subgenus is probably, in my opinion, more closely related to Clivina s. str. and Semiclivina than to Leucocara . Th e only known significant character state shared between Reichardtula and Leucocara is the condition of the preapical setae on each side of sternum VII being proximate. Even if this character is eventually proven to be synapomorphic for these taxa, the clear, unambiguous difference in the mesotibial protuberance would justify the recognition of two distinct subgenera, considering the current classification schema of the genus Clivina .

Acknowledgments

I thank Igor S. Sokolov for notifying me of the presence of two specimens of C. morio in the Louisiana State Arthropod collection and for sending them. I also thank Patrice Bouchard, my co-worker, for reviewing an early draft of this paper and one anonymous reviewer. Both provided judicious comments that improved the presentation of this paper.