A revision of the Phelisterhaemorrhous species group (Coleoptera, Histeridae, Exosternini)

Abstract The Phelisterhaemorrhous species group is established here, revising the seventeen included species, four of which are described as new. This group is named for and contains the type species of Phelister, so represents a core around which a modern concept of the dumping-ground genus Phelister may be developed. The group includes several common and well-known species in the Americas, including some of the only Phelister to exhibit distinctive coloration. Several of these are typically found in cattle dung, and have likely expanded beyond their native ranges as cattle spread throughout the Americas. The group contains the following species: Phelisterhaemorrhous Marseul, 1854, Phelisteraffinis J.E. LeConte, 1859, Phelisterparallelisternus Schmidt, 1893, Phelistermobilensis Casey, 1916, Phelisterbrevistriatus Casey, 1916, Phelistersonoraesp. nov., Phelisterwarnerisp. nov., Phelisterpuncticollis Hinton, 1935, Phelistersubrotundus (Say, 1825), Phelisterrouzeti (Fairmaire, 1850), Phelisterrufinotus Marseul, 1861, Phelisterthiemei Schmidt, 1889, Phelisterparecissp. nov., Phelisterbryantisp. nov., Phelistervernus (Say, 1825), Phelisterchilicola Marseul, 1870, and Phelisterbruchi Bickhardt, 1920. We also designate the following new synonymies: Phelisterhaemorrhous Marseul (= Phelisterrubicundus Marseul, 1889, syn. nov.); Phelistersubrotundus (= Phelistercontractus Casey, 1916, syn nov.); Phelisterrouzeti (Fairmaire) (= Phelisterfairmairei Marseul, 1861; syn. nov., = Phelisterwickhami Casey, 1916, syn. nov.); Phelisterrufinotus Marseul, 1861 (= Epierusmarseulii Kirsch, 1873, syn. nov.); and Phelisterthiemei Schmidt, 1889 (= Phelisterstercoricola Bickhardt, 1909, syn. nov.).


Introduction
With 91 described species, and many more undescribed, the largely Neotropical genus Phelister Marseul is one of the most species rich genera in the family Histeridae. Since its description it has served as a taxonomic dumping ground for a great diversity of small, generally non-descript Exosternini, even including some from outside the Neotropical realm, and phylogenetic analyses have revealed it to be para-and polyphyletic (Caterino and Tishechkin 2015). Recent revisions of some other Neotropical exosternine genera have marginally improved Phelister's coherence by removing a number of species (to Operclipygus Marseul and Baconia Lewis Tishechkin 2013a, 2013b, respectively). However, exactly how to define Phelister itself has not become much clearer, and substantial additional phylogenetic work is needed to more fully understand relationships among the species currently included. Relationships to other as-yet-unrevised genera such as Pseudister Bickhardt, Nunbergia Mazur, and Conchita Mazur remain particularly obscure.
Beyond the phylogenetic questions surrounding Phelister, identification of species in the group is practically impossible without reference to type specimens. No comprehensive (or even partial) keys exist aside from some very local (e.g., Casey 1916) or outdated (Bickhardt 1916) treatments, and the species are very difficult to distinguish based solely on external characters in any case. Yet, accurate identification of some of the species of Phelister has practical significance, as some species have been cited in forensic investigations (e.g., P. rufinotus Aballay et al. 2013) and others have been studied with regard for their potential to control of dung-breeding flies (P. panamensis LeConte; Summerlin et al. 1991), P. rufinotus and P. haemorrhous Marseul (Koller et al. 2002). The species (presumably all predatory) exhibit an interesting array of ecological associations, ranging from loose synanthropy to mammalian inquiliny to myrmecophily. Many also occur in great abundance and may make up substantial fractions of pitfall and flight intercept trap collections in the neotropics. So improved identification efficiency would significantly benefit biodiversity inventory work.
To begin to address these systematic impediments, we plan to revise the species of Phelister over a series of smaller treatments of putatively closely related groups of species. Here we begin with a group of 17 species loosely centered on the now firmlyestablished type of the genus, Phelister haemorrhous Marseul. Previous confusion over the type species of Phelister was resolved by the ICZN following an application to recognize Kryzhanovskij and Reichardt's (1976) designation of P. haemorrhous as the type Tishechkin 2013c, ICZN 2015). Our hypothesis of monophyly for this group is based on only a few shared characters (discussed more below), and the group does contain considerable diversity. But together they seem to represent a near continuum of forms, with many of them quite difficult to distinguish. The group is largely, though not completely supported as monophyletic in our recent global analysis of Phelister (Caterino and Tishechkin 2015). We attribute the exceptions mostly to some inadequacies of search algorithms (across over 750 taxa), as well as a lack of molecular data for the majority of relevant species. Possible relationships among the species are discussed in further detail below, based on some more thorough analyses of a subset of taxa.
The species we attribute to the informal P. haemorrhous group include some of the most commonly encountered Phelister species in both North and South America. Several are associated with the dung of domestic cattle and horses. Additionally, the group includes nearly all of the Phelister species currently known to occur in the Nearctic realm. Interestingly, although the group's species collectively span the Americas, they are sparse in the wet tropics, and the species are most often encountered in the northern and southern subtropical/temperate zones. Furthermore, several of the species exhibit some red coloration, which has drawn an unusual amount of attention to them. Given these attributes, it is a relatively well-described group, with only a few new species, all of which exhibit fairly limited distributions and, in several cases, narrow ecological associations.

Specimens
Type material of all species was examined by one or both of the authors. Other specimens examined were assembled from a large number of institutions:

Phylogenetic analyses
We reanalyzed a subset of taxa from the 750+ taxon data set of Caterino and Tishechkin (2015) to attempt to better resolve species within Phelister and to evaluate the level of support for the haemorrhous group as we delimit it here. This pruned data set included only small numbers of exemplars for those groups previously strongly supported as monophyletic. Specifically, it includes only four species of Baconia, two species of Hypobletus, two species of Operclipygus, and single exemplars of some other smaller but previously supported genera outside Phelister. We also reduced the number of outgroups to six (from 61). This reduced data set included a total of 231 taxa, including all described and undescribed Phelister and Pseudister spp., as well as many other new species of uncertain placement. All taxa were scored for 260 morphological characters. Approximately one-fourth were represented by some molecular data, including some combination of 18S (937 characters for 62 spp.), 28S (993 characters for 32 spp.), and cytochrome oxidase I (679 characters for 63 spp). We did not realign the length variable portions for this reduced dataset, maintaining homology assessments from the preceding analysis. For original alignment parameters see Caterino and Tishechkin (2015). This reduced data set is available as an online supplement (Suppl. material 1). Tree searching was performed in PAUP* (v. 4.0a164;Swofford 2002) under the maximum parsimony criterion, running 1000 random sequence addition replicates, saving no more than 2500 trees for each replicate.

Taxonomy
The Phelister haemorrhous group Diagnosis. Recognizing members of the P. haemorrhous group is difficult, given the general similarity prevailing throughout Phelister. However, most members exhibit most or all of the following character states. There is as yet no single and simple (nonhomoplasious) synapomorphy to which we can point, even in genitalic morphology: • Both mandibles have a strong tooth. A tooth on the right mandible is common outside the P. haemorrhous group; having both teeth is relatively uncommon; • Outer subhumeral elytral stria present, but rarely in more than apical half. Many otherwise similar species have the outer subhumeral longer; • Elytral striae 1-4 complete, 5 th stria variable (but when abbreviated usually represented by a basal puncture); sutural stria abbreviated; • Elytra often with rufescent maculae. There are very few bicolored species of Phelister outside this group; • Body form elongate, less rounded than many Phelister; • Lateral portion of pronotal disk bearing coarser punctures. More rarely present outside this group; • Labrum broad, often weakly emarginate; • Postmesocoxal stria usually well developed, ending freely or recurved anteriad to mesepimeron; • 1 st abdominal ventrite with complete inner and abbreviated outer postmetacoxal stria; • Males of several species have the pronotal keel more densely punctate than the females; most of these species are red-maculate; • Aedeagus usually simple, with apices often variably separated; rarely with ventral dentate process; • Median lobe with proximal apodemes divided into fine proximal and thick distal portions; • Male eighth tergite lacking basal accessory sclerites; • Most species occurring in temperate to seasonal subtropical areas, with few species known from wet tropics.

Phelister thiemei Schmidt, 1889
Phelister stercoricola Bickhardt, 1909, syn. nov . Body elongate-oval, widest behind humeri, humeri slightly wider than base of pronotum; anterior of body black, posterolateral corners of elytra, pygidia, legs, and terminal abdominal ventrites distinctly reddish; entire dorsum finely punctulate, the pronotum more densely so than the elytra; frons finely punctulate, impressed along midline, supraorbital stria complete, frontal stria interrupted at middle, slightly sinuate at sides; labrum wide, distinctly emarginate apically; both mandibles with strong tooth on inner edges; pronotum lacking lateral and anterior submarginal striae; pronotal disk with larger punctures interspersed with finer punctures along lateral thirds; elytron with single, complete epipleural stria, outer subhumeral stria present in apical third, inner subhumeral stria absent, dorsal striae 1-4 com- plete, stria 5 complete or abbreviated at base, and sutural stria obsolete in basal third, diverging from the suture anteriad; propygidium with distinct secondary punctures separated by slightly greater than their widths, denser at sides; pygidium more finely punctate; prosternal keel with two complete striae, finely united by anterior arch, free, diverging posteriorly, finely punctulate between in both sexes; mesoventral marginal stria complete, weakly crenulate, continued at sides by postmesocoxal stria which recurves more or less evenly to anterolateral corner of metaventrite; mesometaventral stria complete, crenulate at middle, curving posteriad to near inner corner of metacoxa; first abdominal ventrite with single, complete lateral stria; protibia with apex obliquely truncate, outer margin weakly rounded, bearing ca. six evenly spaced marginal spines; meso-and metatibiae weakly expanded to apex, mesotibia with ca. five marginal spines, more prominent toward apex, metatibia with distinct spines confined to apical fourth. Aedeagus with basal piece ca. one-fourth total length; tegmen widest just beyond middle, narrowed to apex, apices thin, with deep apical emargination; median lobe short, simple.
Remarks. As the type of the genus Phelister, P. haemorrhous is both typical in many respects, and somewhat unusual. Its distinctive posterior elytral and abdominal coloration is unmistakable, and this, in combination with dentate mandibles, a complete, recurved postmesocoxal stria, complete lateral pronotal stria, and presence of conspicuous lateral pronotal punctures, will easily distinguish it. There are cases where the reddish color is obscure, but the other characters in combination should still allow it to be recognized. While the species' type locality is in Europe (Italy), it is clearly a Neotropical species. There is some uncertainty whether it was ever, in fact, collected in Europe. Vienna (1980) and Penati (2009) specifically dismiss its alleged (e.g., Mazur 1984Mazur , 1997 occurrence in Sardinia, and Penati (2009) furthermore makes a strong case that specimens reported from Sardinia as P. haemorrhous, in fact, represent a species of Epierus (Tribalinae). Earlier, Auzat (1925) suggested that no previous records of Phelister for Europe were bona fide (neither P. haemorrhous nor P. rouzeti). The label on the type of P. haemorrhous does include a question mark after 'Italie', and it seems most likely that Marseul received this in a mixed shipment and never, himself, believed the specimen to have originated in Italy.
This species was recently designated to be the type of Phelister following the suppression of an inadvertent designation of a Baconia species as Phelister's type (Caterino and Tishechkin 2013c;ICZN 2015).
Biology. This species is most commonly encountered in cattle dung. It has also been collected in pitfall traps using a few other types of bait, including human and pig dung. A few specimens have been taken in more general situations, in rotting vegetation (compost) and under the bark of rotten trees.
Distribution. Phelister haemorrhous is among the more widespread Phelister species, extending from Argentina into the southern United States, and possibly having been introduced into Europe (see caveats above). This wide distribution almost certainly owes to its common association with cattle dung, and it has probably expanded its range with cattle production in the New World. Phelister affinis JE LeConte, 1859: 311. Phelister simplex Casey, 1916: 230;Mazur 1997. Phelister solator Marseul, 1861Marseul 1870. Type material. Neotype male, hereby designated: "Tejeria, Veracruz, MEX, VII:4:41" / "Col. by H. Dybas" / "Collection R. L. Wenzel" / "Phelister #68 det R.Wenzel" / "Compared with type Phelister affinis LeC. RLW'51; see type notes under solator"; dissected by Rupert Wenzel (FMNH). The type(s) of this species aren't known, despite searches in the most likely repository (MCZC) and others (FMNH, CMNH, USNM), and despite the apparent fact that Wenzel studied a supposed type in 1951 (labels on specimen). Due to the extreme similarity among members of Phelister, we feel that a Neotype designation is necessary to anchor a specific concept for this species.
Diagnostic description. Length: 1.73-2.01 mm (avg. 1.94 mm); width: 1.50-1.73 mm (avg. 1.65 mm). Body elongate-oval, widest behind humeri, humeri slightly wider than base of pronotum; body more or less uniformly piceous; entire dorsum finely punctulate, the pronotum more densely so than the elytra; frons finely punctulate, impressed along midline, supraorbital stria complete, frontal stria interrupted at sides and at middle, slightly sinuate laterally; labrum wide, distinctly emarginate apically; both mandibles with strong tooth on inner edges; pronotum usually with distinct fragments of submarginal stria in anterior corners; pronotal disk with larger punctures interspersed with finer punctures along lateral thirds; elytron with single, complete epipleural stria, outer subhumeral stria present in apical third, inner subhumeral stria absent, dorsal striae 1-4 complete, stria 5 present in apical half-two-thirds, very rarely complete, but nearly always with a basal puncture, and sutural stria obsolete in basal third, diverging from the suture anteriad; propygidium with distinct secondary punctures separated by slightly greater than their widths; pygidium more finely punctate; prosternal keel with two complete striae, finely united by anterior arch, free, diverging posteriorly, finely punctulate between in both sexes; mesoventral marginal stria complete, smooth, continued at sides by postmesocoxal stria which runs posteriad two-thirds of the distance to metepipleuron; mesometaventral stria complete, weakly crenulate to smooth, angulate mediad mesocoxa, extending posteriad to near inner corner of metacoxa; first abdominal ventrite with single, complete lateral stria; protibia with apex obliquely truncate, outer margin weakly rounded, bearing ca. six evenly spaced marginal spines; meso-and metatibiae weakly expanded to apex, mesotibia with ca. five marginal spines, more prominent toward apex, metatibia with distinct spines confined to apical fourth. Aedeagus with basal piece a little over one-fourth total length; tegmen widest just beyond middle, abruptly narrowed to thin, divided apices; median lobe more than half tegmen length, proximal apodemes thin near base, thickened toward gonopore.
Remarks. This species was previously synonymized with Phelister contractus Casey by Mazur (1997), in error. Having studied its type, we instead synonymize P. contractus with P. subrotundus Say (below).
Biology. Label data indicate rather generalist habitat preferences, having been collected in cow, horse, and gopher tortoise dung, under decayed leaves, in rotting breadfruit, in fire-scorched Yucca L., and in rotten Opuntia Miller, and the species even exhibits some facultative myrmecophily, with records from nests of both Acromyrmex Mayr and Azteca Forel ants.
Diagnostic description. Length: 1.65-1.93 mm (avg. 1.78 mm); width: 1.22-1.58 mm (avg. 1.46 mm). Body elongate-oval, widest at humeri, humeri slightly wider than base of pronotum; body uniformly dark rufescent to piceous; frons finely but distinctly punctulate, somewhat depressed along midline; supraorbital stria complete, frontal stria interrupted across middle; labrum wide, distinctly emarginate apically; both mandibles with strong tooth on inner edges; pronotum with coarse ground punctation throughout, with larger punctures becoming more densely intermingled toward sides; prescutellar impression distinct; lateral and anterior marginal pronotal striae continuous, complete, slightly crenulate at front; submarginal pronotal striae absent; elytron with single, complete, crenulate epipleural stria, outer subhumeral stria present in apical one-third to one-half, inner subhumeral stria absent, dorsal striae 1-5 complete (5 th rarely abbreviated from base); sutural stria present in posterior three-fourths; ground punctation of pygidium and propygidium similarly fine, propygidium with secondary punctures small, sparse, mostly separated by two to three times their widths; prosternal lobe with truncate to weakly emarginate anterior margin, with fine marginal stria; prosternal keel with two complete striae parallel and distinctly united by basal arch, variably connected anteriorly, with faint, secondary basal striae nearer procoxa, finely punctulate between in both sexes; mesoventrite distinctly projecting, marginal stria complete, crenulate, continued at sides by postmesocoxal stria which runs posteriad nearly to metepipleuron; mesometaventral stria complete, weakly crenulate, arched weakly onto basal one-fourth of mesoventrite, extended posteriad by lateral metaventral stria to near inner corner of metacoxa; metaventral disk with few secondary punctures anteromediad metacoxae; first abdominal ventrite with complete inner lateral stria, outer lateral stria nearly complete, often fragmented at base; protibia with apex obliquely truncate, outer margin weakly rounded, bearing 5-6 marginal spines; meso-and metatibiae weakly expanded to apex, mesotibia with ca. five marginal spines, more prominent toward apex, metatibia with distinct spines confined to apical fourth. Aedeagus with distinct ventral process, just basad middle, basal piece short, less than one-fourth total length; tegmen with sides rounded, widest just beyond middle, apices narrowly separated, apical emargination narrow and shallow; median lobe approximately one-half tegmen length, proximal apodemes thin near base, thickened toward gonopore.
Remarks. This species is quite similar to P. affinis, but can be consistently distinguished by its parallel and rather narrowly separated prosternal striae, and its complete 5 th dorsal stria. Its frontal stria is interrupted at the middle, but not at the sides, and it never appears to show any indication of a sublateral pronotal stria.
Biology. The only indications of habits for this species come from a few Oklahoma specimens sifted from 'bay' litter. A couple of specimens were also collected using flight interception traps.
Distribution. The known distribution of this species is oddly disjunct. The types and other early specimens (NHMUK) bear no more specific locality than Mexico. Yet all recent specimens we have seen are from the south-central United States, specifically Oklahoma, Arkansas, and Missouri. It is most surprising that no specimens have been seen from Texas. Records: USA: Arkansas: Faulkner; Missouri: Pike; Oklahoma: Latimer.
Description. Length: 1.85-2.05 mm (avg. 1.93 mm); width: 1.58-1.73 mm (avg. 1.59 mm). Body uniformly dark rufescent to piceous, elongate oval, widest just behind midline; frons finely but distinctly punctulate; supraorbital stria complete, fine across vertex; frontal stria well impressed along inner margin of eyes, fragmentary to obsolete along upper epistomal margin, but continued anteriad along lateral and, generally, apical margins of epistoma; labrum transverse, at most weakly emarginate apically; mandibles both with strong tooth along incisor margin; pronotum strongly narrowed anteriorly, very finely punctate at middle but rather coarsely so in lateral thirds; prescutellar impression distinct; lateral and anterior marginal striae continuous, the anterior diverging slightly from the margin and crenulate; lateral submarginal striae absent; elytra with single, complete epipleural striae; outer subhumeral stria present in apical half only; inner subhumeral stria absent; dorsal elytral striae 1-4 complete, 5 th present in apical half only, sutural stria just slightly longer than 5 th ; propygidium almost uniformly coarsely punctate, punctures separated by less than their widths; pygidium much more finely and sparsely punctate; prosternal lobe shape evenly rounded, with marginal stria obsolete toward sides; prosternal keel narrowed from base to apex; keel striae separate basally, converging between coxae, narrowly separated, parallel anteriad; anterior mesoventral margin weakly produced; marginal mesoventral stria complete, weakly crenulate; mesometaventral stria arching weakly onto basal third of mesoventrite; metaventral disk weakly punctate, with lateral stria nearly complete to inner corner of metacoxa; postmesocoxal stria extending posterolaterad, mostly straight, ending short of apex of metepisternum; abdominal ventrite 1 with one complete and one fragmentary lateral striae, impunctate at middle, increasingly punctate to sides; protibia with apex truncate, outer margin weakly rounded, bearing ca. five prominent, evenly spaced marginal spines; meso-and metatibiae weakly expanded to apex, mesotibia with ca. five marginal spines, more prominent toward apex, metatibia with distinct spines along most of margin; aedeagus gradually widened toward apex, apically rounded with short, narrow apical emargination; median lobe with simple basal apodemes, ca. half tegmen length.
Remarks. Phelister mobilensis exhibits one highly distinct character, a stria on the epistoma lining its anterior and lateral margins, which is continuous with the lateral portion of the otherwise interrupted frontal stria. Other unusual characters include particularly spinose front and middle tibiae, and a meso-metaventral stria which is distinctly more crenulate than the marginal mesoventral stria.

Biology.
Label data indicate quite generalized habitat preferences, with records from dung (dog and chicken), decaying vegetation, Geomys Rafinesque burrows, and fungi. Specimens have also been collected using flight interception traps and Lindgren funnel traps.
Description. Length: 1.81-2.29 mm (avg. 2.03 mm); width: 1.50-1.89 mm (avg. 1.69 mm). Body uniformly dark rufescent to piceous, elongate oval, widest just behind midline; frons finely but distinctly punctulate; supraorbital stria complete, fine across vertex; frontal stria well impressed along inner margin of eyes, continuing mediad above epistoma, but variably interrupted, often in a dense, linear field of punctures along frontal midline, ends generally curved upward, rarely complete and simple; labrum transverse, at most weakly emarginate apically; mandibles both with strong tooth along incisor margin; pronotum with sides subparallel at bases, weakly curved inward to front, disk very finely punctate at middle but rather coarsely so in lateral thirds; prescutellar impression weak, generally present; lateral and anterior marginal striae continuous, the anterior diverging slightly from the margin and crenulate; lateral submarginal striae absent; elytra with single, complete epipleural striae; outer subhumeral stria present in apical half only; inner subhumeral stria absent; dorsal elytral striae 1-4 complete, 5 th present in apical half and represented by a basal puncture, sutural stria slightly longer than fifth; propygidium almost uniformly coarsely punctate, punctures separated by less than their widths; pygidium much more finely and sparsely punctate; prosternal lobe shape evenly rounded, with more or less complete marginal stria; prosternal keel striae separate basally, converging between coxae, thence diverging weakly, usually connected by anterior arch, males with striae more widely separated, and punctures between striae slightly denser and more conspicuous; anterior mesoventral margin weakly produced; marginal mesoventral stria complete, smooth; mesometaventral stria more distinctly crenulate, arching anteriad to middle of mesoventrite; metaventral disk impunctate, lateral stria nearly complete to inner corner of metacoxa; postmesocoxal stria extending posterolaterad, wavering, becoming fragmented posteriad, ending well short of metepisternum; abdominal ventrite 1 with complete inner and fragmentary outer lateral striae, disk impunctate at middle, increasingly punctate to sides; protibia with apex obliquely truncate, outer margin weakly rounded, bearing 6-7 prominent, marginal spines; meso-and metatibiae weakly expanded to apex, mesotibiae with ca. six marginal spines, more prominent toward apex, metatibia with distinct spines along apical third of margin; aedeagus with distinct ventral process near middle, tegmen in dorsal view gradually widened toward apex, apically abruptly narrowed, with short, rather wide apical emargination; median lobe with long, basal apodemes distinctly thicker toward gonopore, nearly as long as tegmen.
Remarks. Of the Phelister species occurring in the southwestern United States and northwestern Mexico, this species can generally be recognized by its frontal stria, which, while usually complete, tends to connect to a series of median longitudinal frontal punctures. These are not always present, however. It seems to be closely related to the two following species, both of which have distinctive characters of their own. Phelister sonorae has modified protarsal claws (perhaps in the male only), while Phelister warneri has more finely impressed dorsal striae, and more finely spinose middle and hind tibiae.
Biology. Label data reveal varied habits for this species. Many specimens were collected in cow dung. A few specimens were taken directly from kangaroo rat (Dipodomys Gray) burrows, and many others were collected using black pitfall traps in the vicinity of Dipodomys burrows, so facultative mammal inquilinism appears likely. Several specimens were also taken from the debris piles of leafcutter ants (Atta mexicana (Smith) and Atta sp. Diagnostic description. Length: 1.97 mm; width: 1.58 mm. This species is externally very difficult to distinguish from P. brevistriatus, especially given the variability and wide geographic distribution of that species (within which P. sonorae occurs). With only a single specimen of this species, we can confidently cite only: male protarsal claws strongly bent at base, straight in apical three-fourths; frons narrower, with frontal stria less strongly impressed, weakly interrupted in denser frontal punctation; ground punctation of pronotal disk coarser and deeper; 5 th dorsal elytral stria nearly complete, continued between stria and basal puncture by a weak crease; male prosternal keel striae not as widely separated, and surface between striae not very conspicuously punctate; aedeagus lacking distinct ventral process, tegmen narrow, only slightly widened at middle, apices acute, separated, apical emargination incised to middle of tegmen; median lobe with short, basal apodemes distinctly thicker toward gonopore, only ca. one-third as long as tegmen.
Remarks. As mentioned in the description, externally this species mostly falls within the range of variation for most characters of P. brevistriatus. Aside from the very distinctive aedeagus, and unusual, probably sex-limited, bent protarsal claw, the only distinguishing feature is the longer 5 th dorsal elytral stria. More material of this species will be necessary to confirm these differences, and hopefully to support the consistency of some other minor characters.
Etymology. We name the species for the state and region of its origin. Biology. Nothing is known of the biology of this species. Distribution. This species is only known from Sonora, Mexico.  1.57 mm). This species is externally very difficult to distinguish from P. brevistriatus, as well as P. sonorae. The following characters should be sufficient to distinguish P. warneri: body distinctly rufescent, with the elytra (except for a linear area right along the suture) vaguely lighter/brighter red than most of the rest of the body, the lateral regions of the pronotum sometimes appearing similarly lighter; frontal stria often interrupted at sides as well as medially, rarely obsolete across the front; frontal disk usually with enlarged median punctures, but not organized into a linear cluster as they are in P. brevistriatus; ground punctation of pronotum more distinct, grading more gradually into denser lateral pronotal punctures; male protarsal claws 'normal', curved, not bent at base (distinct from P. sonorae); elytral striae shallowly and rather finely impressed, 5 th dorsal elytral stria confined to posterior third of elytron, typically fragmented, rarely entirely obsolete; meso-and metatibiae narrower, slightly more elongate, with marginal spines fewer in number and size; 1 st abdominal ventrite with little or no vestige of outer lateral stria; aedeagus with short basal piece ca. one-fifth total aedeagus length; tegmen rather narrow, dorsoventrally flattened, with small ventral process, tegmen sides subparallel, undulating, apices slightly convergent but separate, apical emargination broad and deep, ca. one-third tegmen length; median lobe ca. onethird tegmen length, with simple proximal apodemes.
Etymology. In naming this species for Mr. Bill Warner, we are pleased to recognize his many contributions to our knowledge of histerid biology, taxonomy, and distribution. His efforts led to the discovery of this species, and many others.
Biology. The type series of this species was collected in the same place, and even in the same black cup pitfall traps, as numerous specimens of P. brevistriatus. Black cup pitfalls evidently often attract mammal nest inquilines (the cup imitates a burrow entrance; WB Warner, pers. comm.), and we suggest that P. warneri is a specialized inquiline. The single specimen from Texas was collected in a burrow of black-tailed prairie dog (Cynomys ludovicianus), supporting this assertion. This potential host does extend into southeastern Arizona.
Distribution. This species is mainly known from a single locality in southeastern Arizona. An additional male (which we have dissected) from Brewster Co., Texas, however, conforms in all respects to the diagnosis above. So, the species must be more widespread.  1.29 mm). Body elongate oval, dark rufescent, with elytra lighter toward their apices; frons depressed along midline, disk strongly punctate; frontal striae obsolete between antennal insertions; labrum short, weakly emarginate; both mandibles with distinct median tooth, that of right mandible small; entire pronotal disk almost uniformly punctate, only slightly less dense at middle; prescutellar impression distinct, though somewhat obscured by discal and posterior marginal punctures; marginal pronotal stria complete along lateral and anterior margins, crenulate anteriorly; lateral submarginal stria complete at sides, curving mediad at front, ending freely behind eye; elytra with complete outer subhumeral stria, inner subhumeral stria absent; dorsal elytral striae 1-5 complete, sutural stria obsolete in basal one-third, all striae distinctly crenulate; propygidium almost uniformly punctate, with small round punctures separated by approximately their diameters; pygidial punctures smaller and sparser, fading to indistinct at apex; prosternal lobe short, with fine, complete marginal stria; prosternal keel with striae united anteriorly to form a triangle, the male's more densely punctate within; mesoventrite weakly projecting at middle; marginal mesoventral stria complete, evenly arched anteriad between inner corners of mesocoxae; mesometaventral stria arched strongly forward to mesoventral midpoint, extended by inner mesoventral stria to metacoxa; metaventral disk with distinct ground punctation and coarser punctures along most of posterior third; 1 st abdominal ventrite with complete inner lateral stria and fragments of outer lateral stria; protibia with lateral margin strongly rounded, with 6-7 marginal spines, apex obliquely truncate, with two small apical spurs; protarsal claws somewhat unevenly curved, slightly bent at base; meso-and metatibiae evenly widened to apices, with few weak marginal spines confined to apical halves; basal piece of aedeagus ca. one-fourth total aedeagus length; tegmen narrow at base, widened toward narrowly rounded apex, apical emargination narrow, incised ca. one-fourth of tegmen length, ventral process absent; median lobe with long proximal apodemes, evenly differentiated into thicker and thinner portions.

Phelister puncticollis
Remarks. This species is similar to P. bryanti described below, but differs in the presence of a submarginal pronotal stria, abbreviated, united male prosternal striae, and the presence of punctures on the metaventrite in front of the metacoxae. The aedeagus of P. puncticollis is narrow and evenly rounded to the apex, whereas that of P. bryanti is abruptly narrowed.
Biology. Nothing is known of the biology of this species. Distribution. We have only seen specimens from Pará state, Brazil, including the types, and only three additional specimens, from Belém and Benevides. One specimen was collected in the nest of the fire ant Solenopsis saevissima (Smith). ( Type material. Neotype of Hister subrotundus Say, hereby designated: [pale pinkish round disk] / "892" / "NEOTYPE Hister subrotundus Say Desg. Caterino & Tishechkin, 2011", MCZC. This common, widespread, and somewhat variable Nearctic species needs to be represented by a physical type so as to establish the identity of P. subrotundus, in the event that later work reveals it to represent multiple species. Holotype of Phelister contractus Casey: "Lee Co Tex" / "Casey bequest 1925" / "TYPE USNM 38447" / "contractus Csy.", USNM. This species was previously synonymized, in error, with Phelister affinis by Mazur (1997). Wenzel (unpub. notes) agrees with our assessment.

Phelister subrotundus
Diagnostic description. Length: 1.54-1.85 mm (avg. 1.69 mm); width: 1.30-1.62 mm (avg. 1.52 mm). Body elongate-oval, widest behind humeri, mostly piceous, posterolateral corners of elytra and legs generally reddish; entire dorsum finely punctulate, the pronotum more densely so than the elytra; frons finely punctulate, impressed along midline, supraorbital stria complete, frontal stria interrupted at middle, slightly sinuate at sides; labrum wide, weakly emarginate apically; both mandibles with strong tooth on inner edges; pronotum with more or less complete lateral submarginal stria incurved and crenulate anteriorly, ending freely, and diverging slightly from pronotal margin posteriorly, where it is weakly abbreviated; pronotal disk with larger punctures interspersed with finer punctures along lateral thirds; elytron with single, complete epipleural stria, outer subhumeral stria present in apical third, inner subhumeral stria absent, dorsal striae 1-5 complete, sutural stria obsolete in basal third; propygidium with distinct secondary punctures decreasing in density posteriad; pygidium more finely punctate; prosternal keel with two complete striae, weakly convergent and free anteriorly, usually united along basal margin of keel; male prosternal keel with coarser and denser punctures, the striae often more widely separated and more nearly parallel; mesoventral marginal stria complete, weakly crenulate, close to anterior mesoventral margin, often with corresponding median 'point', continued at sides by postmesocoxal stria which ends freely midway between the meso-and metacoxae; mesometaventral stria complete, crenulate at middle, arched anteriad distinctly onto mesoventrite (with weakly parallel median 'point' to mesoventral stria), curving posteriad to near inner corner of metacoxa; first abdominal ventrite with complete inner lateral stria and abbreviated outer lateral stria; protibia with apex obliquely truncate, outer margin weakly rounded, bearing ca. six evenly spaced marginal spines; meso-and metatibiae weakly expanded to apex, mesotibia with ca. five marginal spines, more prominent toward apex, metatibia with distinct spines confined to apical fourth. Aedeagus with basal piece ca. one-fourth total length; tegmen widened toward apex, apex evenly rounded, with shallow apical emargination; median lobe ca. two-thirds tegmen length, with differentiated basal and distal proximal apodemes. Remarks. Among species occurring in the United States, P. subrotundus is easily separated by the following character states: elytra reddish posterolaterally; frons depressed, with frontal stria interrupted; submarginal pronotal stria present, more or less complete, curved mediad anteriorly and diverging from margin posteriorly; prosternal striae converging anteriorly to nearly parallel, intervening punctures denser in male; elytral stria 1-5 complete. Below we refer to this species and following four (P. rufinotus, P. thiemei, P. rouzeti, and P. parecis) informally as the P. rufinotus complex, and their close relationship is supported by phylogenetic analyses to date.
Biology. The species has diverse and general habits, having been collected very commonly in dung, as well as in decaying vegetation, leaf litter, seaweed on the beach, in pocket gopher (Geomys) burrows, and even with a few ant species (in the genera Aphaenogaster Mayr and Formica L.). A few of the specimens from pocket gopher burrows, including one from Arkansas and four from Georgia, are unusually small and  Diagnostic description. Length: 1.38-1.77 mm (avg. 1.57 mm); width: 1.10-1.46 mm (avg. 1.32 mm). Body elongate-oval, widest behind humeri; body color varied, common with much of elytra (posterolaterally) reddish, more rarely entirely piceous dorsally, legs typically golden reddish, though darker in piceous specimens; elytra and pronotum very finely punctulate; frons finely punctulate, impressed along midline, supraorbital stria complete, frontal stria interrupted at middle, slightly sinuate at sides; labrum wide, not or only weakly emarginate apically; both mandibles with strong tooth on inner edges; pronotum with more or less complete lateral submarginal stria incurved and crenulate anteriorly, ending freely, and diverging slightly from pronotal margin posteriorly, where it is often weakly abbreviated; pronotal disk with distinct, elongate secondary punctures along lateral thirds; base of pronotum with cluster of larger punctures in front of suture; elytron with single, complete epipleural stria, outer subhumeral stria present in apical third, inner subhumeral stria absent, dorsal striae 1-4 complete, fifth stria usually present in just over apical half, rarely complete, sutural stria present in apical two-thirds; propygidium with distinct secondary punctures decreasing in density posteriad; pygidium more finely punctate; prosternal keel with two complete striae, weakly convergent to subparallel, occasionally sinuate, free anteriorly, usually united along basal margin of keel; male prosternal keel with coarser and denser punctures, the males' striae often more widely separated; mesoventral marginal stria complete, continued at sides by sinuate postmesocoxal stria which ends freely midway between the meso-and metacoxae; mesometaventral stria complete, crenulate at middle, arched anteriad onto mesoventrite at middle, continued posteriad to near inner third of metacoxal margin; first abdominal ventrite with complete inner lateral stria and abbreviated outer lateral stria; protibia with apex obliquely truncate, outer margin weakly rounded, bearing ca. five evenly spaced marginal spines plus a larger apical marginal spine separated from others by a greater gap; meso-and metatibiae weakly expanded to apex, mesotibia with ca. five marginal spines, more prominent toward apex, metatibia with distinct spines mainly in apical half. Aedeagus with basal piece ca. one-fifth total length; tegmen simple, widest near middle, converging to apex, apex distinctly emarginate; median lobe ca. two-thirds tegmen length, with differentiated basal and distal proximal apodemes.
Remarks. Although its distribution is rather broad, P. rouzeti seems to be primarily native to western Mexico and southwestern North America. Its distribution only barely overlaps with that of P. subrotundus, its closest relative, from which it can be separated by its more elongate body form, usually abbreviated 5 th elytral stria, and its narrower, more tapered aedeagus. Where it overlaps in distribution with P. rufinotus, in northern South America, the complete submarginal pronotal stria of P. rouzeti will distinguish them. Although the species was originally described from France (Bondy, northeast of downtown Paris), it has never since been recorded in the country, despite dedicated attempts to recollect it (Auzat 1925;M Secq, pers. comm.). While an introduction followed by extirpation cannot be ruled out, it seems more likely that the original specimen was mislabeled, and that the species has never inhabited Europe.
Biology. Label data indicate varied habits for this species, with records from firescorched Yucca, rotten Opuntia, under bark of Celtis L., on a fermenting orange, in cow, dog, and horse dung, and in sifted riparian 'dirt'.
Distribution. This widespread species occurs from the southwestern and southcentral United States, through Mexico and Central America into northern South America. The species also occurs on several islands in the West Indies. As a common cow dung associate, its range has likely expanded in post-Columbian times. Type material. Type locality: "Bresil, Rio-Janeiro". We have been unable to find any specimens that we believe to validly represent syntypes of Phelister rufinotus. Marseul specimens (with circular, green, handwritten labels) are present in MNHN and in NHMUK, but all of these represent other localities and appear to have been collected later ([18]'63' and [18]'68) than the species was described. A couple of specimens in the NHMUK are labeled with variations on Rio de Janeiro, but none as typical for Marseul types, and lacking collection dates, it's impossible to tell if these might have been extant in 1861. We considered designating a Neotype from among the later Marseul-identified specimens. However, we feel that the species is now adequately characterized, and that this would not serve a critical need.
Types  Diagnostic description. Length: 1.46-1.69 mm (avg. 1.56 mm); width: 1.30-1.50 mm (avg. 1.34 mm). Body elongate-oval, widest just behind humeri; body piceous to rufescent, most of elytra and legs usually contrastingly reddish (elytra sometimes nearly black); dorsum very finely punctulate, the pronotum more densely so than the elytra, especially in the outer thirds; frons finely punctulate, impressed along midline, supraorbital stria complete, frontal stria interrupted at middle, inner ends pointing toward epistoma; labrum wide, weakly emarginate apically; both mandibles with distinct tooth on inner edges; pronotal lateral submarginal stria abbreviated, present in anterior half only; pronotal disk with vague antescutellar impression, with crenulations along posterior margin; elytron with single, complete epipleural stria, outer subhumeral stria present in apical half, inner subhumeral stria absent, dorsal striae 1-4 complete, fifth variable, but at least weakened in basal third if not obsolete, sutural stria obsolete in basal third; propygidium with sparse secondary punctures decreasing in density posteriad; pygidium with secondary punctures fewer and finer, diminishing to apex; prosternal keel with two complete striae, weakly sinuate, subparallel at base, slightly converging toward apex, free anteriorly; male prosternal keel with coarser and denser punctures, the striae often more widely separated; mesoventral marginal stria complete, smooth, continued at sides by postmesocoxal stria which ends freely near side of mesoventrite; mesometaventral stria complete, very weakly crenulate, arched anteriad nearly to midline of mesoventrite extended posteriad by lateral metaventral stria toward middle of metacoxa, ending short of it; first abdominal ventrite with complete inner lateral stria and abbreviated outer lateral stria; protibia rather narrow, with apex obliquely truncate, outer margin weakly rounded, bearing ca. five evenly spaced marginal spines, the spine of the apical corner larger and slightly disjunct; meso-and metatibiae weakly expanded to apex, mesotibia with ca. five marginal spines, more prominent toward apex, metatibia with distinct spines confined to apical third. Aedeagus with basal piece ca. one-fourth total length; tegmen widened toward apex, spoonshaped, apex rounded, with narrow apical emargination; median lobe ca. two-thirds tegmen length, with differentiated proximal and shorter distal proximal apodemes.
Remarks. This species is highly variable, but it can nearly always be recognized by its abbreviated submarginal pronotal stria. It is most often distinctly reddish on the elytra, but many all-black individuals have been seen, throughout the range. Its legs are nearly always distinctly golden in contrast to a piceous venter.
This species was previously synonymized with P. fairmairei Marseul 1861. We have studied that type and believe that P. fairmairei is instead identical to P. rouzeti (see above).
Biology. Label data indicate broad ecological associations with records from cow dung, decaying vegetation, meat-and dung-baited pitfalls, and gopher tortoise droppings. The species also exhibits distinct tendencies toward facultative myrmecophily, with numerous records from Acromyrmex and Solenopsis Westwood, and even a few from Eciton Latreille ('with prey').
Distribution. This species occurs most abundantly in southern South America, though numerous records also indicate that it occurs well into the tropics, with records in nearly every other country in the continent. There are several records from the Gulf Coast of the United States (Carolinas, Mississippi and Florida) that would seem likely to represent an introduction, given the lack of intervening records. This is another species that may well have expanded its distribution with the spread of cattle production. Types of synonyms. Lectotype of Phelister stercoricola Bickhardt hereby designated: "Montevideo, J. Tremoleras" / "Type" / "stercoricola Bickh." / "LECTOTYPE Phelister stercoricola Bickhardt, 1909 M.S. Caterino & A.K. Tishechkin des. 2010", ZMHB; five paralectotypes with same data, four in ZMHB, one in NHMUK.
Remarks. We have characterized this species rather broadly. The typical form, from Mato Grosso, has a complete frontal stria and abbreviated 5 th dorsal stria. Considerable variation is observed in these characters from other areas, with the frontal stria more often interrupted elsewhere. Typical P. stercoricola (which we synonymize here) exemplifies this alternative, with an interrupted frontal stria and complete 5 th dorsal elytral stria. However, while there is some variation in genitalic shape over this range (mainly in the degree of apical expansion and approximately parallel sides of the tegmen), there is inadequate consistency to support multiple species at present. More careful study over this species' range may conclude otherwise. Specimens from the Cochabamba region of Bolivia frequently exhibit anterior fragments of a lateral submarginal pronotal stria, but we have dissected these as well and find them to fit within this broad concept of P. thiemei. Phelister rufinotus occurs broadly over much of the same range as this species, but we have generally had little difficulty separating them, on the basis of (in P. rufinotus) a partial lateral submarginal pronotal stria, and the spoon-shaped aedeagus.
Biology. Label data provide limited clues into the habits of this species; a few specimens were collected in cow dung or in pitfalls baited with human dung. Numerous specimens were simply collected by flight interception traps.
Distribution. This species is known from a fairly broad area from southeastern Bolivia and southeastern Brazil in the north through Uruguay and Paraguay south across central Argentina. Diagnostic description. Length: 1.34-1.62 mm (avg. 1.48 mm); width: 1.14-1.30 mm (avg. 1.26 mm). Body elongate oval, dark rufescent to piceous, the elytra more distinctly rufescent; frons depressed along midline, lacking secondary punctures, with complete frontal stria; labrum weakly emarginate; both mandibles with strong inner marginal tooth; pronotum with fine but distinct ground punctation, with coarser punctures in the lateral thirds, as well as along the basal margin; prescutellar impression distinct; marginal pronotal stria complete around sides and front; lateral submarginal pronotal stria complete along sides, very close to marginal stria, curving inward at front, nearly merging with marginal stria behind eye, strongly crenulate; elytra with single, complete epipleural stria, outer subhumeral stria present in posterior one-half, inner absent, dorsal striae 1-5 complete, the 5 th hooked weakly at base, sutural stria present in apical two-thirds; propygidium with conspicuous, round secondary punctures separated by ca. their diameters, only slightly smaller and sparser in apical half; pygidium with very small, sparse secondary punctures throughout; prosternal lobe bluntly rounded, with complete marginal stria; prosternal keel with complete striae, sinuate, united anteriorly, with denser intervening punctures in the male; mesoventrite moderately produced, with complete marginal stria close to margin, continued at sides by long postmesocoxal stria that extends two-thirds of the distance to the posterior corner of the metepisternum; mesometaventral stria weakly arched onto base of mesoventrite, angulate at sides, lateral metaventral stria extending nearly to middle of front edge of metacoxa; 1 st abdominal ventrite with complete inner lateral stria and fragments of outer behind metacoxa; protibia with outer edge rounded, bearing four moderately strong teeth, with prominent spines, apex obliquely truncate; protarsal claws unmodified; meso-and metatibiae weakly expanded to apices, bearing marginal spines, principally in the apical half on the metatibia; basal piece ca. one-fourth aedeagus length; tegmen narrow, only weakly expanded to apex, not very dorsoventrally flattened, rather thick in apical half; median lobe over half tegmen length, proximal apodemes differentiated with thin basal portions long.
Remarks. This species is very closely related to the P. rufinotus complex, and we considered the possibility that it represented a variant of one of these. But it is consistently distinct, over several localities, in the complete lateral submarginal pronotal stria, the complete 5 th dorsal stria, and the complete frontal stria. Its aedeagus (from only one available male) is narrower than others in this complex, as well.
Biology. Nothing is known of the biology of this species. Distribution. This species is known from only three locations, from Mato Grosso, Brazil to southern Paraguay.  Diagnostic description. Length: 1.50-1.77 mm (avg. 1.62 mm); width: 1.22-1.38 mm (avg. 1.29 mm). Body broadly elongate oval, piceous, with conspicuous ground punctation, especially on pronotum; frons depressed along midline, lacking secondary punctation, with complete supraorbital stria; frontal stria obsolete between antennal bases; labrum moderately emarginate apically; both mandibles with strong inner marginal tooth; pronotal disk with few coarser secondary punctures at sides of disk and along basal margin; prescutellar impression present, but small; marginal pronotal stria complete along sides and front, crenulate anteriorly; submarginal pronotal striae absent; elytra with single, complete epipleural stria; outer subhumeral stria present in apical half only, inner absent, elytral striae 1-5 complete, sutural stria present in apical two-thirds or slightly more; propygidium with few sparse secondary punctures, mostly in basal half; pygidium with ground punctures only; prosternal lobe bluntly rounded, with complete marginal stria; prosternal keel with complete striae parallel over most of length, slightly divergent basad, connected basally by transverse stria, free anteriorly; mesoventrite moderately strongly produced, with complete marginal stria, continued at sides by postmesocoxal stria which diverges sinuately onto metaventrite; mesometaventral stria subangulate at middle, reaching midpoint of mesoventrite, curving posteriad at sides rather distant from mesocoxa, continued by lateral metaventral stria nearly to middle of metacoxa; 1 st abdominal ventrite with single, complete lateral stria; protibia with outer margin weakly rounded, widest near middle, with 5-6 weakly developed teeth bearing marginal spines, apex obliquely truncate; protarsal claws (of male only?) strongly bent at base, straight to apex; meso-and metatibiae elongate, thin, mesotibia with ca. five thin marginal spines, those of metatibia very fine and mostly near apex; basal piece ca. one-fourth total aedeagus length; tegmen moderately flattened dorsoventrally, lacking ventral process, sides widening to near apex, then abruptly narrowed to thin, elongate apices, apical emargination narrow; median lobe ca. one-third tegmen length, with proximal apodemes differentiated into thin and longer thick portions.
Remarks. This species appears quite similar to P. puncticollis, but is distinct in lacking a sublateral pronotal stria, its impunctate metaventrite, and separate male prosternal striae. The aedeagus of P. bryanti is highly distinct, being abruptly narrowed apically, where that of P. puncticollis is narrow and evenly rounded to the apex.
Etymology. This species is named for the collector of the entire type series, GE Bryant, a British coleopterist, best known for his work on Chrysomelidae.
Biology. Nothing is known of the biology of this species.
Distribution. This species is only known from the type locality in northeastern Argentina, and the types' labels bear no ecological data.
Remarks. Among US species of Phelister, P. vernus is easily distinguished by its broadly interrupted frontal stria, its lack of submarginal pronotal stria, and its conspic-  1.66 mm). Body elongate oval, widest behind humeri, piceous with the apices of the elytra and the legs typically castaneous to rufescent, the ground punctation fine but distinct; frons depressed along midline, lacking secondary punctures; supraorbital stria complete, frontal stria fine, interrupted at middle for ca. width of labrum, inner ends weakly recurved dorsad; labrum weakly emarginate; mandibles both with distinct inner marginal tooth, that of left mandible slightly larger; pronotal disk with few coarser secondary punctures at sides and row of coarse punctures along posterior margin; prescutellar impression present but weak; marginal pronotal stria complete along sides and front, not distinctly crenulate anteriorly; submarginal pronotal stria absent; elytra with single, complete epipleural stria, outer subhumeral stria present in apical half, inner subhumeral stria absent; dorsal striae 1-4 complete, 4 th rarely abbreviated at base, 1 and 2 weaker apically, 5 th stria present in apical half, sutural stria present in apical two-thirds; propygidium with small, sparse secondary punctures, mainly in basal half; pygidium with ground punctation only; prosternal lobe evenly rounded, with complete marginal stria; prosternal lobe with two complete striae converging slightly toward front, the intervening punctures not sexually dimorphic in density; mesoventrite weakly projecting, with complete marginal stria, continued at sides by postmesocoxal stria which diverges to sides, ending freely before reaching middle of metepisternum; mesometaventral stria straight to angulate at middle, often reaching middle of mesoventrite, continued at sides by well-impressed lateral metaventral stria which reaches middle of metacoxa; 1 st abdominal ventrite with complete inner lateral stria, the outer generally abbreviated from both base and apex; protibia with outer margin distinctly rounded, widest near middle, with five weakly developed teeth bearing marginal spines; protarsal claws of both sexes strongly bent at base, then straight; meso-and metatibiae evenly widened to apices, with few weak marginal spines confined to apical halves; basal piece of aedeagus ca. one-fourth entire aedeagus length; tegmen dorsoventrally flattened, with weak ventral process ca. onethird from base, tegmen widening toward apex, sides rounded, apices bluntly rounded, with narrow, rather shallow apical emargination; median lobe a little over one-half tegmen length, proximal apodemes thin at bases, thicker over apical two-thirds.
Remarks. This species is superficially similar to other red-marked species, such as P. haemorrhous, P. rufinotus, and P. thiemei. However, it is clearly and easily distinguished from any of these by its thin elytral striae, modified protarsal claws (in both sexes), and more diffuse reddish coloration of the elytra only. The aedeagus is also quite distinct from any of these, particularly in the obvious ventral process of the tegmen, and in the short proximal apodemes of the median lobe.

Phelister bruchi
Diagnostic description. Length: 2.01-2.05 mm (avg. 2.04 mm); width: 1.73-1.77 mm (avg. 1.76 mm). Body elongate oval, moderately depressed, rather pale rufescent; frons with fine ground punctation, weakly depressed at middle, frontal stria interrupted briefly at middle; labrum deeply emarginate, apical margin subcarinate; mandibles both strongly toothed along inner edge; pronotum with sides strongly convergent, only weakly curved, disk impunctate at middle, with sparse larger punctures at sides; prescutellar impression very small, fine; punctures along basal margin weak; marginal pronotal stria complete along sides and front; submarginal striae absent, but three gland openings conspicuous along lateral margins; elytra with single, complete epipleural stria, outer subhumeral stria very short and apical, inner subhumeral stria absent; dorsal elytral striae 1-3 complete (3 rd may be weakly abbreviated apically), 4 th present in basal third, and maybe as apical fragments, 5 th and sutural striae absent; propygidium with sparse small punctures separated by 2-3× their diameters, also with faint wavy microsculpture near base; pygidium with only very small and ground punctation; prosternal lobe rather elongate, with complete marginal stria; prosternal keel narrow, lacking striae; mesoventrite projecting, with marginal stria fine, merging with margin at middle, thus appearing interrupted; mesometaventral stria absent from mesoventrite; postmesocoxal stria present curving strongly laterad behind coxa; lateral metaventral stria present, extending from inner margin of mesocoxa ca. two-thirds the distance to outer corner of metacoxa; 1 st abdominal ventrite with only weak fragments of a lateral stria; all legs rather elongate and slender; protibia with lateral margin rounded, with 6-7 marginal spines, apex obliquely truncate; protarsi elongate, with almost straight protarsal claws; meso-and metatibiae narrow and elongate, with rather fine, elongate marginal spines, those of metatibia restricted to apical half; basal piece short, ca. one-sixth total length of aedeagus narrow, sides subparallel, apices bluntly rounded, with shallow apical emargination; median lobe long, ca. four-fifths tegmen length, proximal apodemes differentiated into thick and longer thin portions.
Biology. This species has only been collected once to our knowledge, from burrows of Ctenomys Blainville (tuco-tucos). Its habitus, with long thin legs and weakly impressed striae, reflects its probable status as an obligate inquiline in these burrows.
Distribution. This species is only known from the type locality, in Buenos Aires province, Argentina.

Results and discussion
In our reduced analysis of Phelister (sensu lato) a single 'best' island of trees was found (saving the maximum 2500 trees) of 10777 steps. Continuing with an unconstrained search, beginning with these shortest starting trees, one shorter island of trees of 10766 steps was found. The majority rule consensus of these is presented in Figure 10. Fifteen Figure 10. Majority rule consensus of 1000 trees of 10766 steps from parsimony search. Majority rule consensus indices are shown on branches. Taxa that are highlighted in green are members of the Phelister haemorrhous group, as delimited in this paper (including two not resolved to be part of the same clade, P. vernus and P. warneri). One species, P. pulvis, resolved among P. haemorrhous group species but excluded from the group is highlighted in red.  The first is that two species that we have included in the haemorrhous group based on overall morphology do not fall in it in these analyses. Omission of one of these, Phelister vernus, corresponds to some of our own uncertainties with its assignment. It instead falls out with a Central American group of Phelister species that includes P. pusio Erichson, P. canalis Lewis, and P. miramon Marseul. The latter placement is somewhat intriguing, in that P. miramon was considered initially to be P. vernus (in Marseul's writing on his own label for the type of P. miramon). However, we have studied type(s) of P. miramon (Caterino & Tishechkin, unpublished notes), and, despite some external similarities, it represents a distinct species with a very different type of aedeagus from anything in the P. haemorrhous group. This phylogenetic result may be driven more by superficial external characters than more significant internal ones. More surprising is the wide separation of our new species P. warneri from the P. haemorrhous group. This may also be driven by some unique external characters associated with its inquilinous habits, as its aedeagus shares several characteristics with other species in the haemorrhous group (especially P. brevistriatus and P. sonorae, which we suggest to be its closest relatives.) The second problem is that Phelister pulvis Marseul falls among members of the P. haemorrhous group, though we have not included it in this revision. It is difficult to see the basis for its inclusion, as its external similarity is minimal, lacking most of the characters that we list above as diagnostic for the haemorrhous group. This unlikely result is probably driven by the lack of male genitalic data available for P. pulvis, hindering its placement with species we do consider to be its more likely relatives.
Within the haemorrhous group, P. haemorrhous itself is resolved as sister to all other members of the group, with the North American P. mobilensis then sister to the remainder. Phelister brevistriatus and P. parallelisternus are united as sister groups, somewhat surprisingly to the exclusion of P. affinis. What we informally refer to as the 'rufinotus complex' is resolved as a clade. Remaining relationships show relatively little correspondence with obvious morphological characters, and demand more comprehensive analysis. Only four of these species are yet represented by any molecular data (P. haemorrhous, P. subrotundus, P. rufinotus, and P. vernus). More comprehensive data will be necessary to reveal more valuable insights into relationships.