Notes on <I>Dubiraphia</I> (Coleoptera: Elniidae) With
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Notes on Dubiraphia (Coleoptera: Elniidae) with Descriptions of Five New Species1 WILLIAM L. HILSENHOFF Department of Entomology, University of Wisconsin, Madison 53706 ABSTRACT Because of the brevity of original descriptions, the included, as new species, D. brevipennis, D. browiii, I), status of Dubiraphia east of the Rocky Mountains has been minima, D. parva, and D. robusta, in addition to I), confused, with /). vittata (Melsheimer) and D. quadri- quadrinotata and D. vittata. Descriptions and a key to notata (Say) frequently being considered synonyms. the 8 species in the Central United States are presented Only /). bhnttata (LeConte) was being correctly identi- to permit their separation, and genitalia of the 10 species fied. A study of the genitalia revealed that the vittata- known to occur in the United States are figured. (]uadrinotata complex in the Central United States also Downloaded from https://academic.oup.com/aesa/article/66/1/55/23410 by guest on 01 October 2021 Tti 1954, Sanderson placed 5 species of elmids in especially useful. The shape of the parameres is also a new genus, Dubiraphia. Two, D. brumicscens (Fall useful; wrinkles on the membraneous inner margins 1925) and A ginlianii (Van Dyke 1949), are found (Fig. 1 B, E, I) are artifacts of mounting. The in California and can be readily distinguished (Van ventral shield appears to be of no taxonomic value, Dyke 1949). The other 3 species occur east of the and the phallobase was not used because it is fragile Rocky Mountains. /). bivittata (LeConte 1852) has and frequently mutilated when the genitalia are usually been correctly identified because it is dis- removed. tinctly larger, but /). quadrinotata (Say 1825) and All Dubiraphia are very similar morphologically, /). vittata (Melsheimer 1844) have caused much differing mostly in size, color pattern, and male confusion. They have, frequently been considered genital structure. Within a species there are often synonyms, probably a result of LeConte's statement wide differences in general coloration. In D. vittata, (1852) that "Dr. Melsheimer's species, as I know for example, the color of the pronotum ranges from by actual inspection, is only an immature specimen piceous to testaceous. At first a species difference of the not unusual variety with the spots confluent was suspected, but corresponding differences could forming a vitta." not be found in the genitalia. In individuals with a A study of male genitalia of Dubiraphia collected piceous pronotum, other structures such as the vittae, in Wisconsin revealed 4 species in the quadrinotata- legs, venter, gula, etc., are dark, and in those with a vittata complex, and additional material from Okla- testaceous pronotum these structures are correspond- homa and Louisiana loaned to me by Harley Brown ingly light. Color differences seem to be related to contained 3 more species. A complete generic revi- habitat, with beetles from the same stream having sion is needed, but other commitments did not permit less variation in coloration. Variations in size were me to undertake this task. The results of this pre- also noticed when populations from different streams liminary study are presented to permit identification and especially from different regions of the country of species known to occur in the Central United were compared. D. vittata adults from southern States and to stimulate additional study of this States average smaller than those from Wisconsin. genus. In this paper, I will figure the genitalia of all In Wisconsin, D. vittata can be readily separated known species (Fig. 1), expand descriptions of D. from D. minima by its larger size, but D. vittata vittata, D. bivittata, and D. quadrinotata, describe 5 from Tennessee and Ohio are near the size of D. new species, and provide a key to species known to minima. occur in the Central United States. Except for types of D. vittata and D. bivittata T have placed much reliance on the male genitalia and specimens of D. ginlianii and D. bnawescens, for separation of species. Because of their extremely all beetles examined in this study were preserved small size, genitalia were mounted on microscope in 70% ethanol. Occasionally specimens were coated slides dorsal side up in Hoyer's medium. In all spe- with debris. Encrustations were readily removed by cies the aedeagus has a dorsal keel in at least the placing beetles in concentrated HC1 for ca. 30 sec. basal half and is curved ventrad near the apex. a technique that has been very valuable in cleaning Within most species there are variations in the size other elmids, especially Stenclmis. The location of and shape of the aedeagus. The extreme variations type specimens is detailed under each species. Other suggested possible species differences, but series re- specimens that were studied are housed in the Uni- veal many shapes and sizes between the extremes. In versity of Wisconsin insect collection or in the spite of variations, the aedeagus is the most valuable Stovall Museum at the University of Oklahoma. character for separating species. A sheath near the Because of similarity in morphology and coloration tip has a dorsal straited area (Fig. 1 B, F) that is among all Dubiraphia, characteristics possessed in common by all species studied are described below 3 Published with the approval of the Director of the Research Division, College of Agricultural and Life Sciences. Research in detail, expanding on the generic description by supported in part by a grant from the "Wisconsin Department of Sanderson (1954), and are not repeated under the Natural Resources. Received for publication May 17, 1972. 55 56 ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA [Vol. 66, no. 1 Downloaded from https://academic.oup.com/aesa/article/66/1/55/23410 by guest on 01 October 2021 FIG. 1.—Dorsal view of genitalia of Dubiraphia. A, D. quadrinotata; B, C, D. vittata; D, I), bivittata; E, I), robusta; F, G, D. minima; H, D. browni; I, D. brcvipcnnis; J, D. prava; K, D. brunncsccns; L, D. giulianii. Scale on each photomicrograph = 100 turn. January 1973J HILSENHOFF: NOTES ON DubirapJiia 57 descriptions of each species. The length of the elytra Legs.—All legs subequal, prothoracic legs slightly (measured with the base and apex in the same plane) shorter. Femora and tibiae with scattered setae and was relied upon as a measure of size, rather than fine punctures separated by 1-4 times the diameter overall length, which varied depending on the pos- of a puncture. Area between punctures with reticu- ture of the beetle at death. The length of the aede- late sculpturing and fine pubescence. Inner margins agus was measured from the midpoint of a line be- of tibiae with several bristlelike setae, a patch of tween the knoblike basolateral angles of the median tomentum on distal fourth, and a pair of apical lobe to its apex. The "striated area ratio" was spines. Last tarsal segment subequal to preceding obtained by measuring the distance from the apex four, with short spines on the inner sides of all seg- of the aedeagus to the point where striae were no ments. Tarsal claw simple, hooked, ca. % length of longer distinct, and dividing by the total length of last tarsal segment. the aedeagus. The following key is presented to separate species of Dubiraphia in the Central United States. Although Downloaded from https://academic.oup.com/aesa/article/66/1/55/23410 by guest on 01 October 2021 Dubiraphia Sanderson 1954 the key is to males, it may be used for females if one Head.—Black, with large continuous patch of flat, keeps in mind that they usually are 5-10% larger pale tomentum behind and below each eye. Remainder than males. Species can be identified without ex- of head sparsely covered with light hairs and fine amining genitalia, but the genitalia are diagnostic punctures separated by 1—4 times the diameter of a and should be examined to confirm identifications. puncture. Area between punctures glabrous. Gula often much lighter in color. Maxillary palpi 4-seg- Key to Species of Dubiraphia in the Central United mented. Antennae testaceous to rufotestaceous, slen- States (Males) der, 11-segmented, and extending almost to posterior 1. Large, length of elytra 2.1-2.4 mm. Aedeagus ca. 5 margin of prothorax. times as wide as parameres at midlength (Fig. 1 Pronotum.—Sides slightly sinuate in basal third, D) D. bivittata Smaller, length of elytra 1.9 mm or less. Aedeagus then conspicuously narrowed to apex. Widest just not more than 3 times as wide as parameres at behind middle, but only slightly wider than at base. midlength 2 Pronotum at anterior margin %-% as wide as at 2. Usually quadrinotate; if vittate, vittae cover only posterior margin. Anterior margin broadly rounded, 3rd interval at basal third. Elytra 1.6-1.9 mm long. Aedeagus thin and sword-shaped, 400-470 with projecting anterolateral angles. Posterior mar- /tm long (Fig. 1 A) D. quadrinotata gin slightly concave on each side of middle, which Vittate; if quadrinotate, elytra less than 1.5 mm is slightly more caudad than lateral margins. Con- long. Aedeagus less than 400 /tm long and as vex above and sparsely covered by pale setae and wide or wider than parameres at midlength 3 3. Elytra at least 1.6 mm long. Aedeagus broad with moderate punctures separated by Y>-2 times the base of striated area close to midlength (Fig. 1 diameter of a puncture. Area between punctures B, C, E) 4 glabrous with only a hint of sculpturing. Elytra less than 1.6 mm long. Aedeagus variable . 5 Elytra.—Elongate, nearly parallel sided in basal 4. Robust species, width of pronotum 0.75 mm or greater. Aedeagus more than 335 /tm long (Fig. -:'i and then narrowed to a rounded apex.