Olibroporus Casey, 1890

Gimmel, Matthew L., 2017, Taxonomic Notes onOlibroporusCasey andPycinusGuillebeau (Coleoptera: Phalacridae), with Diagnosis and Distribution of the Widespread SpeciesOlibroporus punctatusCasey, The Coleopterists Bulletin 71 (1), pp. 61-73: 62-63

publication ID

http://doi.org/ 10.1649/0010-065X-71.1.61

persistent identifier

http://treatment.plazi.org/id/03EA8799-E10C-FF92-FD32-BF0CFBF40279

treatment provided by

Carolina

scientific name

Olibroporus Casey, 1890
status

 

Olibroporus Casey, 1890   , sensu   novo

Olibroporus Casey 1890: 111   . Type species: Olibroporus punctatus Casey, 1890   , fixed by monotypy.

Pycinus Guillebeau 1893: 289   . Type species: Pycinus politus Guillebeau, 1893   , fixed by subsequent designation. New synonymy.

Ochrodemus Guillebeau 1893: 293   . Type species: Ochrodemus brevitarsis Guillebeau, 1893   , fixed by monotypy. Synonymized with Pycinus   by Gimmel (2013: 68).

Radinus Guillebeau 1893: 295   . Type species: Radinus latus Guillebeau, 1893   , fixed by monotypy. Synonymized with Pycinus   by Gimmel (2013: 68).

Parasemus Guillebeau 1894: 281   . Type species: Parasemus grouvellei Guillebeau, 1894   , fixed by original designation. Synonymized with Olibroporus   by Gimmel (2013: 61).

Euphalacrus Champion 1925: 608   . Type species: Euphalacrus crassipes Champion, 1925   , fixed by original designation. Synonymized with Pycinus   by Gimmel (2013: 68).

Notes. In light of examination of additional members of Olibroporus   and Pycinus   from the Neotropics, I have concluded that the diagnoses of these two genera outlined in Gimmel (2013) are untenable since some specimens possess a mix of characters. Previously, I distinguished Pycinus   by the presence of a ventral ridge on the mandible, lack of abdominal calli (in species so far examined), absence of strong microsculpture and presence of spectral iridescence on the elytra, extremely densely setose prosternum medially, and the more robust antennal club. Additionally, males of many species of Pycinus   have an enlarged second protarsomere. However, I examined intermediate specimens ( Brazil: Nova Teutonia, 27°11′S, 52°23′W, 300–500 m, Fritz Plaumann, December 1972 [AMNH]) with strong microsculpture (and no spectral iridescence), an extremely densely setose prosternum, and a robust antennal club with an emarginate terminal antennomere. A dissected male specimen from Brazil formed the original basis for my assertion that a second species of the restricted concept of Olibroporus   occurred in the New World ( Gimmel 2013: 63). The only totally consistent character observed that separates the two previous concepts of Olibroporus   and Pycinus   is the reduced amount of setae on the prosternum in the former. Therefore, I consider these two generic concepts to grade into one another and see no reason to arbitrarily maintain a generic distinction for O. punctatus   alone. Additionally, the species in question share some highly specific character states, which are illustrated here for the first time using scanning electron microscopy. These are the presence of comb-like grooves on the elytra ( Fig. 13 View Figs ; also shared with three other genera, see Discussion below) and a unique shape of the mesoventral plate ( Fig. 15 View Figs ). An additional unique putative synapomorphy is the bidentate condition of the mandibles with a row of short blunt teeth on the dorsal cutting edge, further reinforcing the status of Olibroporus   + Pycinus   as a cohesive group. In the morphological phylogenetic analysis of Gimmel (2013), O. punctatus   and two representatives of Pycinus   were placed in a polytomy along with other members of the “ Olibroporus   -group”. A molecular phylogenetic study will be necessary to accurately assess relationships within this genus.

Olibroporus sensu novo   now possesses 13 valid species, all distributed in the Neotropical region, with only O. punctatus   extending into the Nearctic region. A few synonyms probably exist among these names, and new species have been seen. In particular, I have examined a form that seems to belong to this genus but possesses an antennal club of five antennomeres ( Brazil; BMNH), and at least one other with a flattened body and testaceous coloration (widely distributed in the Neotropics).

Diagnosis. Adult members of this genus may be recognized by the combination of lack of a ctenidium on the outer edge of the protibia; metaventral process not protruding anterior of the mesocoxae ( Figs. 15 View Figs , 24–26 View Figs ); metaventral postcoxal lines not separated from coxal cavities ( Fig. 16 View Figs ); small scutellar shield (width at base less than diameter of eye); metatarsomere I shorter than II ( Fig. 17 View Figs ); mandible with apex bidentate (and with a dorsal row of small, blunt teeth); and elytra with a single sutural stria ( Fig. 11 View Figs ) and either strong microsculpture ( Fig. 12 View Figs ) or spectral iridescence. Another important character, which is quite difficult to observe in dry specimens with a light microscope, is the disposition of the “mesoventral plate” (central part of the mesoventrite delimited by strong sutures), whose lateral sutures bend abruptly laterad just before reaching the margin of the mesocoxal cavity and trace the anterior border of the meso- coxa, without connecting to the cavity or any suture ( Fig. 15 View Figs ; see also line drawings in Gimmel 2013: figs. 17f, 19f). This state is unique to Olibroporus   . Other members of the Olibroporus   - group ( Austroporus   , Platyphalacrus   ) also possess incomplete lateral sutures of the mesoventral plate, but these evanesce in the middle of the mesoventrite (see Gimmel 2013: figs. 16f, 18f). One character shared by all members of the genus is the transverse band of grooves near the basal margin of the elytron (see Discussion for elaboration of this structure). A complete redescription of the new concept of Olibroporus   will be presented in a future contribution along with a revision of the species.

CHECKLIST OF THE SPECIES OF THE GENUS OLIBROPORUS   (original genus in parentheses)

Olibroporus brevitarsis ( Guillebeau, 1893)   , new combination ( Ochrodemus   ) [ Venezuela]

Olibroporus crassipes ( Champion, 1925)   , new combination ( Euphalacrus   ) [ Brazil]

Olibroporus guatemalenus (Sharp, 1888)   , new combination ( Olibrus   ) [ Guatemala, Panama]

Olibroporus hemisphaericus ( Guillebeau, 1893)   , new combination ( Pycinus   ) [ Venezuela]

Olibroporus latipes (Sharp, 1888)   , new combination ( Olibrus   ) [ Panama]

Olibroporus latus ( Guillebeau, 1893)   , new combination ( Radinus   ) [ Venezuela]

Olibroporus microsternus (Sharp, 1888)   , new combination ( Olibrus   ) [ Panama]

Olibroporus politus ( Guillebeau, 1893)   , new combination ( Pycinus   ) [ Venezuela]

Olibroporus punctatus Casey, 1890   [ USA to Brazil]

Olibroporus rubiginosus (Sharp, 1888)   , new combination ( Olibrus   ) [ Guatemala, Mexico]

Olibroporus subrotundatus ( Guillebeau, 1893)   , new combination ( Pycinus   ) [ Venezuela]

Olibroporus tropicus ( Kirsch, 1873)   , new combination ( Phalacrus   ) [ Colombia]

Olibroporus vulgaris (Sharp, 1888)   , new combination ( Olibrus   ) [ Guatemala]

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Phalacridae

Loc

Olibroporus Casey, 1890

Gimmel, Matthew L. 2017
2017
Loc

Euphalacrus

Gimmel, M. L. 2013: 68
Champion, G. C. 1925: 608
1925
Loc

Parasemus

Gimmel, M. L. 2013: 61
Guillebeau, F. 1894: 281
1894
Loc

Pycinus

Guillebeau, F. 1893: 289
1893
Loc

Ochrodemus

Gimmel, M. L. 2013: 68
Guillebeau, F. 1893: 293
1893
Loc

Radinus

Gimmel, M. L. 2013: 68
Guillebeau, F. 1893: 295
1893