a ContriBution to tHe KnoWledGe of sPeCies of tHe triBe aCratini froM PanaMa and frenCH Guiana ( Brentidae : traCHeliZinae ) *

This paper lists the species belonging to the tribe Acratini (Alonso-Zaragoza, Lyal, Bartolozzi & Sforzi, 1999) (Brentidae: Trachelizinae) in Panama and French Guiana; some of them are reported for first time in Panama: Acratus diringshofeni Soares, 1970; Acratus bellus Soares, 1970; Acratus mendax, Soares, 1970; Nemobrenthus helmenreichii (Redtenbacher, 1868) Comb. Nov., and Proteramocerus disparilis Soares & Dias, 1971; likewise Acratus pohli Soares, 1970 and Teramocerus punctirostris are recorded for first time in French Guiana, also I made mention of species recently recorded in both countries by Mantilleri (2015). Meanwhile, nomenclatural position of each one species is updated. Their taxonomy, diagnosis, type depositories, geographical distribution, material examined, and other relevant details are presented for each species.

From among the unidentified material stored in museums and insect collections in Panamá and French Guiana, I report seven new records of Acratini in both countries.A complete diagnosis to identify the species and distribution maps are presented.
All species examined for this paper were collected from 1969 to 1993 in Panamá, and 2001 to 2012 in Commune La Regina and Cacao, French Guiana; specimens and external structures were examined using a Leica GZ-6 stereomicroscope.Panamanian specimens were photographed using a Canon SX-500 camera and the Visionary Digital Passport optical equipment; photographs of French Guiana specimen are courtesy of Jean-Louis Giuglaris, each of them was edited using GIMP (GNU Image Manipulation Program) (KIMBAL et al., 2008).For brentid species, determinations were made using the published descriptions of SHARP (1895), KLEINE (1927), SOARES (1970), SOARES & DIAS (1971), SOARES & SCIVITARO (1972) and MANTILLERI (2015a).Indeed, taxonomical classification of tribe Acratini is controversial; many authors (SHARP, 1895;KLEINE, 1927KLEINE, , 1938;;SOARES & DIAS, 1971;SOARES & SCIVITTARO, 1972) stablished the genera Proteramocerus, Teramocerus, Acratus and Nemobrenthus; according MANTILLERI (2015) based in misinterpretations and wrong descriptions; a thorough examinations of sclerites and internal sac of aedeagus and phylogenetical analyses can stablish that Proteramocerus and Acratus are artificial taxa and moving as synonyms of Teramocerus; some Proteramocerus and Teramocerus species recently have been moved to new genera Rugosacratus and Teramoceroides respectively; thus, for species taxonomy and new combinations I followed the proposal of MANTILLERI (2015a,b,c), but keeping traditional taxonomy of Acratini at genera level (other Acratus and Proteramocerus which haven't been accommodate yet in a new taxon are remarked with a * in the key) described on this paper and make some comments about taxonomic position changes (remarks).Distributional data were imported into Map Creator 2 (PRIMAP SOFTWARE, 2007) for mapping based on published information by SHARP (1895); SOARES & DIAS (1971); WOLDA et al. (1998), andSFORZI &BARTOLOZZI (2004).

diagnosis:
A. diringshofeni is recognized by the following set of features: head longer than broad, rostrum ventrally without dense pubescence, prothorax reddish-brown, opaque, pyriform, with three longitudinal black bands, one in the median groove and one on each side; elytra green with golden highlights, elytral suture, I-II striae and I-II interstriae reddish-brown; elytral apex reddish-brown, rounded; pro and mesofemora clubbed, metafemora not laminate at base.diagnosis: Head longer than broad, rostrum ventrally densely pubescence; prothorax pyriform-shaped, evenly green without bands; elytra green with bronze highlights according the light incident, elytral suture, I-II striae and I-II interstriae reddish-brown, post-median black blotch; elytral apex rounded, elytral declivity reddish-brown; pro and mesofemora clubbed, metafemora laminate at base.diagnosis: A. mendax is recognized by the following combination of characters: head wider than long, prorostrum slender, barely dilated at apex; antennae reach the middle of prothorax, 1-8 antennomeres are conical, 9-11 cylindrical, last antennomere acuminate; prothorax pyriform, dorsally green-purple; elytra green without golden highlights, elytral declivity and caudal appendices purple.The species can be distinguished from A. gracillipes by the size of the rostrum; all tarsal segments are the same length (A.gracillipes first tarsal segment as long as 2nd and 3th tarsal segment together).Nemobrenthus is a small group of medium size brentids that resemble Acratus by the sturdy body, head and rostrum are shorter, collar constriction well marked; prothorax pyriform longer than broad, longitudinally grooved, not punctate; elytral apex rounded without apical tooth; femora not pedunculate; at base, dorsal part of femora slightly flattened and grooved.Differs them by first tarsal segment broader than long; shorter than 2-3 together, looking sub-equals; tarsomeres 2-3 impressed on upper side; tarsomere 2 broader than long.diagnosis: N. helmenreichii can be recognized by the following combination of characters: body reddish brown, elytra strongly metallic green, dark post-median elytral blotch hardly distinct; head not punctate, interocular fovea weak but distinct.antennae short, antennomeres 2-8 broader than long, 9-10 longer than broad, 11 two times as long as 10. examined material: Cerro Campana, Aug. 13, 1974, H.P. Stockwell, 1 (♂), 5 (♀) (STRI); Cerro Campana, Aug. 17, 1974, H.P. Stockwell, 2 (♀) (STRI) remarks: N. helmenreichii was described on the one female specimen by Lund (1800) as Trachelizus helmenreichii, nevertheless, Kleine and Soares place T. helmereichii as a synonym of Teramocerus suturalis (Acratus); this concept as understood erroneously by them and referring completely different species according MANTILLERI (2015b).For this reason he propose remove it from synonymy.
Proteramocerus is a group of slender brentids that differs from Acratus by the head very long, longer than broad, antennae longer or shorter at least just reaching the neck, prothorax slender, elytra with thorn-shaped caudal appendices present in both sexes or at least in males, or rarely absent, legs slender, femora clubbed, first tarsal segment at most as long as the length of 2nd and 3rd together.
diagnosis: P. disparilis is recognized by the following set of features: body dark-brown, slender; head very long, dorsally glabrous with transversal striae, antennae with third antenomere longer than others; prothorax strongly longer, than broad, smooth, rhomboid-like appearance, apically with transversal striae, longitudinally grooved; elytra without obvious puncturation, elytral apex rounded without an evident declivity; femora clubbed; first tarsal segment as long as the length of 2nd and 3rd together.Rugosacratus is new genera proposed by Mantilleri 2015, differs from Proteramocerus by the following set of characters: Head weakly punctuated with numerous transverse wrinkles clearly visible (especially in males).Head without or with only a few sensory pores.Below the suture head gular fairly marked without sensory pores behind the median post-ocular fovéole.Antennae longer reaching the metarostrum, antennomeres much longer than wide, segments 2-8 significantly widened at the apex; 9-10 subcylindrical to ovoid slightly narrowed at the base.First tarsal segment much longer than wide, longer the following two together; Abdomen elongated sternites III-IV non-depressed or furrowed, punctuated on sides.
diagnosis: this species is recognized by the following set of features: body darkbrown, elytra metallic green, slender, head and prothorax dorsally with transversal striae, rostrum longer, strongly sulcate dorsally from metarrostrum to prorostrum, antennae long, third antennal segment longer than other antennal segments; prothorax laterally with irregular outline, elytra with regular punctures, elytral suture blackish.The genus Teramoceroides proposed by MANTILLERI (2015c) differs from its brother group Teramocerus by the following set of characters: below rostrum male with very long bristles, sensory pores well above the base of the prorostrum forward.Antennomeres 9-10 longer than wide, cylindrical.Pronotum furrowed, not punctuated.First tarsal segment more long as wide, the first article of the metatarsal longer than males following two together.
Teramoceroides belti (Sharp, 1895) (Figure 12) diagnosis: According Sharp (1895), T. belti can be recognized by the following set of features: rostrum of male densely covered with setae beneath, its upper surface is remarkable in being raised along the middle, making it bisulcate; head beneath is wrinkled and the sides of the prosternum are granulate; elytra are of a beautiful silky metallic-green color with the suture purplish red.This group differs from Acratus and Proteramocerus by the great elongation of the first tarsal segment and the length of the antennae, which extend beyond the prothorax and body much slender.
diagnosis: Teramocerus punctirostris is distinct among the species of Teramocerus by possessing the following set of features: body brown, slender, prothorax laterally with soft irregular outlines; elytra with one yellow band on each side, elytral suture and post-medial blotch blackish, elytral apex not spiny.distribution map:  remarks: According MANTILLERI (2015) T. rileyi is only known in Panama, however, it's may be more widespread in Central America.
In conclusion identification of Acratini species without study of the genitalia, it will be very difficult to properly identify most of Acratini as descriptions and keys given by Soares and Scivittaro are not reliable at moment.Indeed, they often based their conclusions on observations by Lacordaire or Schoenherr (especially for type species of the different genera) and those observations are almost always outdated now.Moreover, as their studies focused only on external features, they were blurred by the extraordinary variability inside a same species, leading to descriptions of several synonyms.A comprehensive study of the genitalia will understand this group and other groups of Brentidae, their phylogeny and taxonomy relations in the future.aCKnoWledGeMents This study would not have been possible without the help of the following persons.I would like to thank Diomedes Quintero and Roberto Cambra (MIUP), Héctor Barrios and César de León (PCMENT), Edwin Domínguez and Annette Aiello (STRI) for the loan of undetermined material and provided photographs of A. mendax, A. bellus, T. belti and T. rigely; my sincerely thanks to Jean-Louis Giuglaris who provided photographs of A. pohli, R. eximius and T. punctirostris.I also thank Antoine Mantilleri (MNHN), Yolanda Moreno de Niño (UP-CRUC) and Annette Aiello (STRI) for their support, useful comments and review in English.The author will never forget the constant support his wife Ursula Vargas-Cusatti gave him.