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 back to Key to Genera & Species Using the Key / States DescribedBEST MODEIn order to allow for the fastest identification possible, it is strongly encouraged the user make use of the "Best" feature in the Lucid3 player. This button (located on the top tool bar, represented as a magic wand) automatically selects the "best" character for you to use. Once selected, the key will automatically jump to the next "best" character, re-calibrated due to your previous selections. Occasionally, a character is presented that may be too difficult, may not be visible, or perhaps may not be known for a given specimen (e.g., the head has fallen off, or there is no locality data, or it is a "male" character and you are unsure of the sex). In these situations, it is advisable to select the "Next best" button and skip to the next best feature remaining. This course of action is preferred over guessing at the states of features if you are unsure. FEATURE / STATE EXPLANATIONS Given below are definitions and explanations for the features and states that may be interpreted differently and/or sometimes appear ambiguously. GEOGRAPHIC OCCURRENCE Regional occurrence: this is based on an observation by Karl Stephan (1989) that while many of the genera are widely distributed throughout North America, the vast majority of the species either occur on the eastern or western side of the 100th meridian. This is a very useful distributional character. The 100th meridian passes through more or less the center of North Dakota and South Dakota, the western 1/3 of Nebraska and Kansas, the handle of Oklahoma, and the western 1/3 of Texas (see image). State occurrence: this character is only scored for the taxa where occurrence in a particular state or states within the United States aids in identification. This scoring is by no means comprehensive and should not necessarily be used to completely eliminate taxa, as new distributions will undoubtedly be discovered. BODY General Shape: Elongate, cylindrical is defined as the length being several times the width of the beetle, and there is little question of the cylindrical nature (e.g. Nematidium, Eudesma, Lobogestoria, Antilissus). Flattened or sub-depressed is defined as the body not distinctly elongate and cylindrical, but not dorsally and ventrally convex. This is the standard state for most of the Zopheridae of this region, and encompasses a variety of forms. Oval, dorsally and ventrally convex is defined as distinctly oval or elliptical in shape with the lateral margins nearly evenly curved throughout, and both dorsal and ventral surfaces exhibiting some degree of convexity. This is found within the Monommatini (Hyporhagus, Spinhyporhagus, and Aspathines. HEAD Antennae Antennal club – Number of segments: The antennal club is here defined as beginning with the antennomere that is a departure in size or shape from the previous antennomeres. While the club segments may be indistinct in some (Rhagodera), usually the 9th, 10th, or 11th antennomere is greatly enlarged or of a different shape than the preceding segments. In some taxa (e.g. Eucicones), the terminal segment bears an annulation in which the apical half is densely setose. This setose portion may be mistaken for a distinct segment, but should not be scored as such. To define seperate segments, there should be a very clear suture separating antennomeres from one another, and generally a difference in size of the club segments, with the connecting margins not completely flush (e.g. Lobogestoria, Endeitoma). Antennal club – structure: Loose is defined as the club segments not completely abutting one another, with the connecting margins not completely flush. The segments may be very loose (e.g. Rhagodera) to slightly loose (e.g. Coxelus). All taxa with a 1-segmented club were scored as "compact." Compact is defined as the club segments completely abut one another, the connecting margins being completely flush (e.g. Acolobicus). If one antennomere is distinctly smaller than the other but flush with the preceding (e.g. Endeitoma), this was scored as "compact." Mouthparts Labial palpi insertion – separation: Approximate is defined by the insertions of the labial palpi being nearly approximate, with little discernable space between each palpus that the base. This is the most common state for the group (e.g. Nematidium). Moderately to widely separated is defined by the bases of the labial palpi being distinctly separated from one another (e.g. Phloeodes). Head Capsule Antennal groove beneath eye – Presence: Antennal groove absent is defined as lack of a clear, well-delimited groove or channel below the eye in which the antennae rests when retracted. Several taxa (e.g. Coxelus) have a raised subgenal brace and a clearly protruding eye, but the space between the eye and subgenal brace is wide and slightly depressed. This is not considered an antennal groove because it is not delimited. Other taxa have a clearly delimited antennal groove/cavity on the prothoracic hypomeron, but no distinct groove on the head capsule itself (e.g. Usechus, Usechimorpha, Zopherus). In this case, the antenna rests across the eye and then fits into the hypomeral antennal groove. Antennal groove present is defined as the presence of a clear, well-delimited groove or channel below the eye in which the antennae rests when retracted. This groove may be short or long, extending to hind margin of eye or beyond (e.g. Eucicones, Acolobicus), straight or curved. In some, the antennal groove is simply a clearly depressed (but defined) area near the antennal insertion. Eyes – Eye facets: Eye facets fine is defined as the individual eye facet not distinctly protruding, eye facets more or less forming a smooth surface. Eye facets coarse is defined as the individual eye facet distinctly protruding, eye facets more or less forming a rough, raspberry like surface. THORAX Prothorax – Pronotum Mid-lateral secretory pore: Pronotum with obvious mid-lateral secretory pore is defined as the presence of a clear pore near the lateral margin of the pronotum at middle. This pore secretes an exudate which aids in the adherence of debris to the dorsal surface, therefore the specimen must be thoroughly cleaned for the pore to be visible. This character is only present in two genera (Lobogestoria, Antilissus) Pronotum without mid-lateral secretory pore is defined as no such pore being present. Pronotal width – anterior and posterior: Pronotum distinctly wider anteriorly than basally is defined by the anterior portion of the pronotum greatly expanded, or the pronotum tapering strongly towards the base. This should not be scored if the lateral margins are arcuate with the anterior portion only slightly wider than basal portions. Pronotum subquadrate or distinctly wider basally than anteriorly is defined as the pronotal width being nearly equal or distinctly wider basally than anteriorly. This should be scored if the lateral margins are arcuate with the anterior or basal portion slightly wider than opposite portions. Sublateral carinae on pronotal disc – presence: Pronotum with paired sublateral carinae is defined by the presence of a distinct pair of carinae located sublaterally on the pronotal disc. Most often, these carinae are straight to subtly curved to slightly sinuate, but never complexly sinuate or forming an interlacing network (as in Sesaspis, Lasconotus). Pronotum lacking paired sublateral carinae is defined by the absence of a distinct pair of carinae located sublaterally on the pronotal disc. In cases where the pronotal carinae (if present at all) are complexly sinuate or forming an interlacing network (as in Sesaspis, Lasconotus), this was scored as lacking. Metathorax – Metacoxae Metacoxal separation: Metacoxae nearly contiguous or narrowly separated, intercoxal process usually acute is defined at the distance between the metacoxae distinctly less than 0.75x the width of one coxa. Metacoxae moderately to widely separated, intercoxal process usually broadly rounded to truncate is defined at the distance between the metacoxae around or more than 0.75x the width of one coxa. ELYTRA Elytral ornamentation: Elytra without carinae or tubercles is defined as the lack distinct, cuticular carinae and/or tubercles on the elytra. Raised areas of setae are not considered tubercles, and elytral intervals that are slightly elevated (but not distinctly raised or keeled, as in some Lasconotus) are not considered carinate. Elytra with carinae or tubercles is defined as the presence of distinct, cuticular carinae and/or tubercles on the elytra. In some taxa (e.g. some Lasconotus), suberect setae that converge at the elytral margins may give the impression of underlying carinae, but in fact are not. There must be distinct tubercles or well-defined carinae for the state to be scored. Elytra color/pattern – presence: Elytra solid colored, patterned is defined as the cuticle of the elytra unicolorous, not creating a distinct, clearly visible pattern, regardless of setae color. Elytra bi-colored and with patterns/maculations is defined as the cuticle of the elytra varying in color to create a distinct, clearly visible pattern. Setae that are lighter or darker in color than the elytra and form a pattern should not be scored. LEGS Protibia – spine: Apex of protibia without stout, apical spine(s) is defined as lacking any sort of distinct, stout, curved spine or pair of straight, stout spines. Apex of protibia armed with single, stout, curved apical spine is defined as having such spine (e.g. Aulonium, Colydium, Lasconotus, Nematidium). Generally the spine is as long as or slightly longer than the first tarsomere. For taxa in which the apex of the protibia bears a single short spine or row of spines, these should not be scored for this state. Apex of protibia armed with two subequal, short, stout, straight spines: In some taxa (most Zopherini), the apex of the protibia (and usually all tibia) bears a single or pair of straight, short, stout spines. These are distinct from the previous state in that they are shorter, paired, and not distinctly curved. |
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 © 2011-2015 Lord, N.P., Nearns, E.H., and K.B. Miller |
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