Operclipygus hospes (Lewis, 1902)

Caterino, Michael S. & Tishechkin, Alexey K., 2013, A systematic revision of Operclipygus Marseul (Coleoptera, Histeridae, Exosternini), ZooKeys 271, pp. 1-401 : 124-126

Operclipygus hospes (Lewis, 1902) Figs 34 B–D36A–EMap 12

Phelister hospes Lewis, 1902: 236; Pseudister hospes : Hinton (1935e: 15); Operclipygus hospes : Wenzel (1976: 258).

Type locality.

Unknown, the original type locality in New York State, USA is wrong (see below).

Type material.

Lectotype male, here designated: "Ulster Co., N.Y." [in error; Wenzel, 1976] / "LECTOTYPE Phelister hospes Lewis M.S.Caterino & A.K.Tishechkin des. 2010" (BMNH). This species was described from an unspecified number of specimens, and the lectotype designation fixes primary type status on the only known original specimen.

Other material.

BRAZIL: Pará: 1: Tucuruí, 3°45'S, 49°40'W, 9-17.xii.1985, FIT (CHND).

Diagnostic description.

Length: 1.75-1.78 mm, width: 1.37-1.40 mm; body rufobrunneus, elongate oval, sides subparallel at middle; frons and epistoma slightly depressed at middle, epistoma slightly elevated relative to frons; sides of frontal stria rounded, central portion complete, slightly outwardly arcuate at middle; supraorbital stria more or less complete, narrowly separated from sides of frontal; antennal club with upper basolateral sensory pit; pronotal disk with deeply impressed, elongate prescutellar impression, nearly twice as long as scutellum, acuminate anterad; pronotal disk with ~16 moderately coarse punctures posterolaterad recurved end of anterior submarginal stria, not extending to margin; lateral submarginal stria slightly abbreviated posterad, may be interrupted at middle; anterior submarginal stria crenulate, recurved straight posterad for ~1/6 pronotal length; median pronotal gland openings present just beyond apices of recurved anterior stria, nearly one-fourth pronotal length from anterior margin; elytra with outer subhumeral stria present in apical half, inner subhumeral stria absent, striae 1-3 complete, 4th stria barely abbreviated at base, 5th stria present in apical half; sutural stria present in apical three-fourths; prosternal keel weakly produced posteriorly, carinal striae short, close, weakly convergent to front, united posteriorly and anteriorly, by narrow arch about one-third keel length from presternal suture, keel distinctly narrowed anterad arch; mesoventrite emarginate, marginal stria complete; mesometaventral stria shallowly subangulate forward onto mesoventral disk, continued posterolaterad by lateral metaventral stria, extending obliquely toward outer corner of metacoxa, bent outward at apex; 1st abdominal ventrite with two complete, subparallel lateral striae, inner tending to continue mediad along basal margin; propygidium with moderately large, shallow punctures separated by about half their diameters; pygidium with dense ground punctation, coarser punctures irregularly interspersed, slightly denser toward basal margin; marginal pygidial sulcus complete, deep but rather fine, inner edge crenulate, outer edge smooth. Male genitalia (Figs 36 A–E): accessory sclerites present; T8 elongate, sides subparallel in middle half, basal apodemes slightly divergent, apices roundly narrowed, apical emargination deep, acute, basal emargination deep, broad, basal membrane attachment line distad emargination by about one-sixth its depth, ventrolateral apodemes most strongly developed before middle, narrowly separated at midline; S8 with sides broadly rounded in basal three-fourths, apical guides developed only in apical fourth, very narrow, rounded at apices, halves approximate at base, diverging to apex; T9 widest one-third from base, with subacute angle at this point, weakly narrowed to base, sinuately narrowed to apex, apices subtruncate, rather broad; T10 with halves separate along midline; S9 broad, narrowed at middle, markedly desclerotized along midline, base broadly rounded, lateral flanges wide, apex with narrow median emargination, apical flanges well developed, separate; tegmen widest about one-third from apex, weakly narrowed to base, rounded to subacute apex, apex rather strongly curved downward, with weak subapical cleft visible in lateral view, medioventral process well developed, long, its apex distinctly truncate, strongly projecting beneath about one-third from base; basal piece about one-fourth tegmen length; median lobe about two-thirds tegmen length, nearly half of this length made up of very long filamentous portions of proximal apodemes.

Remarks.

The only named species of the Operclipygus hospes group is also one of its most difficult to characterize. The type does not correspond perfectly to any other material that we have studied, and it is conceivable that it is a somewhat aberrant individual, noting that the lateral submarginal pronotal striae are not exactly bilaterally consistent (interrupted on one side, complete on the other). The true type locality of this species is unknown. 'Ulster Co., N.Y.' is clearly an error. Wenzel (1976) considered Santarém, Pará, Brazil a good possibility, for reasons unknown to us. This uncertainty in type locality is extremely unfortunate, as that would provide some clue as to whether its distinctness might result from being an outlying locality relative to most other material examined. The closest match we have is indeed a specimen from Pará ( Tucuruí), but it is not identical.

Operclipygus hospes is very closely related to the following species, and they could almost be lumped in a single polymorphic entity, but the following exhibits a number of distinctive character states (detailed below), and is significantly larger, so we choose to recognize it separately. These two species are also enigmatic in the larger scheme of the hospes group. They both have a distinct basolateral sensory pit on the antennal club (Fig. 4I), which is otherwise restricted to species near Operclipygus gratus (below), but have genitalia with a shorter, apically truncate medioventral aedeagal process. The subapical cleft of the aedeagus that is found in Operclipygus ignifer and others is, however, very poorly developed in Operclipygus hospes (Fig. 36E).

The citation of Operclipygus hospes by Corréa et al. (2012) as a species of potential forensic importance in southern Brazil refers instead to the closely related Operclipygus subterraneus sp. n. described below.

In this species and the 13 that follow (through Operclipygus innocuus ) all have the medioventral process of the aedeagus narrowed but distinctly truncate at the tip, rather than acute (e.g., Figs 36 E–M), an apparently good synapomorphy. Generally in these the tegmen itself has a weak cleft, or dentate process near the apex. Many have the 8th sternite broadly rounded, widened basally (Fig. 36B). However, while this helps to place many species in the larger Operclipygus hospes group, it is not exclusive to these species. In the last three species here ( Operclipygus communis , Operclipygus belemensis and Operclipygus innoccus ) the accessory sclerites are very small, the 8th tergite exhibits distinctive apicodorsal sclerotizations (Figs 38 E–F), and the 9th sternite is strongly sclerotized.