Minyomerus reburrus [JF2015] Jansen & Franz sec. Jansen & Franz (2015)

Jansen, M. Andrew & Franz, Nico M., 2015, Phylogenetic revision of Minyomerus Horn, 1876 sec. Jansen & Franz, 2015 (Coleoptera, Curculionidae) using taxonomic concept annotations and alignments, ZooKeys 528, pp. 1-133 : 44-49

Taxon classification Animalia Coleoptera Curculionidae

Minyomerus reburrus [JF2015] Jansen & Franz sec. Jansen & Franz (2015) sp. n. Figs 25, 26

Diagnosis.

Minyomerus reburrus [JF2015] is distinct from other congenerics in having irregular rows of copious setae on the elytra, where the setae do not form regular rows as in most other species. The setae are generally a lighter color, and are arranged in offset rows on the intervals, particularly near the elytral suture and declivity. The elytra are somewhat pyriform and weakly punctate. The pronotum is medially incurved on both the anterior and posterior margins. The head is distinctly conical in appearance, and is curved medially. The metatibiae are apically strongly convex and covered with setae similar in length to the surrounding setae, somewhat translucent, and slightly lamelliform. The spermatheca has the ramus elongate, somewhat swollen and sub-apically situated on the corpus.

Description - female.

Habitus. Length 4.15-4.37 mm, width 1.66-1.83 mm, shape greatly elongate and ovate, length/width ratio 2.39-2.52, widest at anterior 1/3 of elytra. Integument dark brown to black. Scales with variously interspersed colors ranging from white to manila/tan to dark coffee brown, in some specimens appearing semi-translucent (in others opaque) or with bluish or yellowish undertones; dorsal patterning fairly stable in this species, having alternating brown and whitish stripes on prothorax and elytra. Setae short, recumbent, off-white to yellow.

Mandibles. Covered with white to yellow scales, with 3 longer setae and 1-2 shorter interspersed setae.

Maxillae. Cardo bifurcate at base with an inner angle of 160-170°, inner (mesal) arm 2 × longer than outer arm, inner arm of bifurcation equal in length to apically outcurved arm. Stipes sub-quadrate, 1.5 × wider than long, roughly equal in length to inner arm of bifurcation of cardo, with 1 lateral seta. Galeo-lacinial complexmembranous; setose in posterior 2/3; dorsally with 5 apicomesal lacinial teeth; ventrally with 4 reduced lacinial teeth. Palpiger with a transverse row of setae near anterior 1/3; anterior 1/3 membranous, posterior 2/3 sclerotized.

Maxillary palps. Palpomere I with apical end facing mesally and forming a 60° angle with base, I and II each with 2 apical setae.

Labium. Prementum roughly pentagonal, convex laterally; apical margins incurved ventrally, straight dorsally, medially projected (ligula), angulate; lateral margins weakly incurved; posterior margin rounded; each lateral region with 1 long seta. Labial palps 3-segmented, I with apexnot projecting beyond margin of prementum, II reaching beyond apexof ligula; I and II both with 1 apical seta; III slightly longer than II, with articulation faint between segments.

Rostrum. Length 0.50-0.58 mm, anterior portion 1.5-1.75 × broader than long, narrower than head, rostrum/pronotum length ratio 0.62-0.66, rostrum length/width ratio 1.19-1.37. Dorsal outline of rostrum sub-rectangular, anterior half of dorsal surface strongly impressed. Rostrum in lateral view rectangular; apical margin with 2 groups of 3 large vibrissae, each group inserted just laterad of each sinuation. Nasal plate well defined by V-shaped, impressed lines, mesally planar, integument covered with white scales. Margins of mandibular incision curved, directed 25-30° outward dorsally in frontal view. Ventrolateral sulci defined, beginning as a sulcus dorsad of insertion point of mandibles, running parallel to scrobe, becoming fainter posteriorly and running into a weakly impressed fovea ventrally. Dorsal surface of rostrum with a short, linear, median fovea at posterior end of nasal plate. Rostrum ventrally lacking median fovea and foveae in line with insertion point of mandibles. Oral cavity with lateral margins curved.

Antennae. Dorsal margin of scrobe overhanging slightly and forming a small tooth, anterior to margin of eye by 1/3 of length of eye. Club similar in length to funicular antennomeres IV-VII, 2.25-2.5 × as long as wide.

Head. Eyes with posterior margin not elevated from lateral surface of head; eyes separated in dorsal view by 3.5-4 × their anterior-posterior length, set off from anterior prothoracic margin by 1/3 of their anterior-posterior length. Head between eyes coarsely, deeply punctate and bulging.

Pronotum. Length/width ratio 0.74-0.81, sub-cylindrical to globular; median sulcus absent. Anterior margin incurved mesally, posterior margin incurved mesally. Constricted region elevated and produced dorsally; scales forming 2 parenthesis-shaped, whitish stripes dorsally, laterally with a whitish stripe that continues onto elytron. Pronotum in lateral view with setae extending beyond anterior margin by 1/2 their length. Anterolateral margin with a tuft of post-ocular vibrissae present, emerging near ventral 2/5-1/2 of eye, becoming gradually, evenly longer ventrally, stopping below ventral margin of eye; vibrissae achieving a maximum length 1/2-3/5 × anterior-posterior length of eye.

Pleurites. Metepisternum exposed only as a minute triangle anteriorly, covered by elytron posteriorly.

Thoracic sterna. Mesosternum with anterior 1/3 incompletely covered by plumose scales, posterior portion as remainder of body surface; mesocoxal cavities separated by distance 1/5 × width of mesocoxal cavity. Metasternum with transverse sulcus apparent; metacoxal cavities separated by 1.5-2.0 × their width.

Legs. Profemur/pronotum length ratio 1.03-1.15; profemur with distal 1/5 produced ventrally as a semicircular projection covering tibial joint. Protibia/profemur length ratio 0.94-0.98; protibia in cross section sub-circular; protibial mucro present as a laterally projected tooth. Protarsus with tarsomere II 2/3 × length of III, equilateral, globular; I and II jointly similar in length to V. Metatibial apexwith almond shaped convex ity ringed by 11-13 stout, spiniform setae.

Elytra. Length/width ratio 2.69-3.53; widest at anterior 1/3; anterior margins after constriction jointly 2-2.5 × wider than posterior margin of pronotum; lateral margins gently curving after anterior 1/3, more strongly rounded and converging in posterior 1/3. Posterior declivity angled at nearly 60° to main body axis. Elytral striae punctate; punctures clearly visible, separated by 2-4 × their diameter; intervals slightly elevated; dorsally with a median longitudinal whitish stripe, laterally with a white stripe laterally continuing from pronotum.

Abdominal sterna. Ventrite III with midregion ventrally concave anteriorly, posterior margin elevated and set off from IV along lateral 1/3 of its length. Sternum VII mesally 1/2 × as long as wide, sub-triangular; anterior margin straight; posterior margin arcuate.

Tergum. Pygidium (tergum VIII) sub-cylindrical; medial 1/3 of anterior 2/3 of pygidium less sclerotized, sclerotized regions porose.

Sternum VIII. Lamina sub-triangular; lateral edges each incurved forming a 60° angle with spiculum ventrale; sclerotized region porose; posterior margin mesally slightly incurved.

Ovipositor. Coxites slightly sclerotized anteriorly, strongly sclerotized in posterior 1/2, 2 × as long as broad; styli 1/3-1/4 × length of coxites, attachment to each coxite nearly straight, with 3-5 long setae near base.

Spermatheca. Comma-shaped; collum short, 1/3 × as long as corpus; collum sub-contiguous with, and angled at 90° to ramus; ramus elongate and slightly bulbous, nearly equal in length and width to corpus; corpus not swollen, of equal thickness to collum and ramus; cornu elongate, apically, gradually narrowed, strongly recurved in basal 1/5, sinuate along mesal 2/5, and curved near apical 2/5 such that apexis parallel to collum and corpus, 2-2.5 × joint length of collum and corpus.

Male.

Not available or known.

Etymology.

Named in reference to the highly setose aspect of the dorsum; reburrus = one with bristling hair; Latin noun in apposition, thence invariable ( Brown 1956).

Material examined.

Holotype - female "TEX. Bailey Co., 3 1/2 mi. SW. Muleshoe, 7-V-1971, G.B. Marshall/ on Artemisia [sic.] [non-focal]" (CWOB). Paratypes, same label information as female holotype (CWOB: 80 females); "NEW MEXICO: Eddy Co., 32°23.2'N, 103°46.6'W, (Site 13) 24 April 1979, Burke, Delorme, Schaffner" (TAMU: 6 females).

Distribution.

This species has been found in the desert and arid regions of New Mexico and Texas (USA) (Fig. 51).

Natural history.

Associated with sagebrush ( Artemisia [non-focal] sp.; Asteraceae [non-focal]). This species is putatively considered parthenogenetic, given the lack of male specimens across a range of sampling events.