PSYCHE A RE-EVALUATION OF THE CHECKERED BEETLES FROM THE UPPER MIOCENE OF FLORISSANT, COLORADO (COLEOPTERA: CLERIDAE)

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1 PSYCHE Vol No. 2-3 A RE-EVALUATION OF THE CHECKERED BEETLES FROM THE UPPER MIOCENE OF FLORISSANT, COLORADO (COLEOPTERA: CLERIDAE) BY JONATHAN MAWDSLEY Department of Entomology Museum of Comparative Zoology Cambridge, MA USA INTRODUCTION The clerid fauna of the Upper Miocene shales of Florissant, Colorado, has received relatively little study since the descriptive papers of Wickham (Wickham 1913:15-16 and Wickham 1914: ). Four species were recorded by Wickham from Florissant: Hydnocera wolcotti Wickham 1913:15-16; Enoclerus florissantensis Wickham 1914:448; Enoclerus pristinus Wickham 1914:449; and Necrobia divinatoria Wickham 1914: Upon careful examination of the specimens available to Wickham, it has become apparent that at least three of these species were assigned to incorrect genera. Enoclerus pristinus actually belongs in the genus Epiphloeus Spinola; Enoclerus florissantensis actually belongs in the genus Thanasimus Latreille; and a new genus, Miohydnocera, is created for Hydnocera wolcotti. Terminology in descriptions follows that of Ekis (1977). Manuscript received 2 June

2 130 Psyche [Vol. 99 Family CLERIDAE Subfamily PHYLLOBAENINAE Genus MIOHYDNOCERA, New Genus Description: Head wider than long, greater in width than prothorax. Eyes large, lateral. Antennae terminating in a distinct club. Pronotum much wider than long, possessing a large anterior tubercle on either side. Femora expanded distally. Scutellum triangular. Elytra emarginate, arcuate along epipleural margin, bearing large punctures on the apical fourth, rather short, exposing at least four abdominal segments. Elytral apices slightly rounded, divergent. Metathoracic wings present, large, venation similar to other Phyllobaeninae but anal veins greatly reduced. Abdomen long, broad. Overall length mm. One species, Hydnocera wolcotti Wickham, hereby defined as the type-species of the genus, is placed here. There are no extant species. This genus is presently only known from the Upper Miocene of Florissant, Colorado. Etymology: Mio-, referring to the Miocene of Florissant from which the type species was collected, and -hydnocera, a synonym of the genus Phyllobaenus Dejean by which the species of the genus Phyllobaenus were known for over one hundred years. Miohydnocera wolcotti (Wickham) NEW COMBINATION References: Wickham 1913:15-16; Wickham 1914:449. Original description: "Form rather stout. Head short and broad, and, including the eyes, probably a little wider than the prothorax, sculpture extremely minute, consisting of only a fine alutaceous roughening. Antennae not well preserved, but the club seems fairly distinct. Prothorax very broad, about one and a half times as wide as long, the sides not entirely perfect but evidently narrowing to the base, a strong transverse anterior impressed line, surface similar to that of the head. Scutellum moderate, triangular. Elytra much shorter than the abdomen, not striate, but strongly sparsely punctate towards the apices which are somewhat narrowed and separately rounded as well as distinctly beaded. Abdomen exposing at least four segments behind elytra tips, sutures strongly sinuate, projecting backwards at middle. The dorsal ventral segments are

3 1992] Mawdsley--Cleridae 131 without any well defined sculpture. Legs stout. Length, 5.35 mm" (Wickham 1913:15). Redescription: Head short, broad, wider than pronotum. Eyes very large, angulate along interior margin, similar in form to those of species of the genus Omadius Laporte. Pronotum much wider than long, bearing a large tubercle on either side. Femora expanded laterally at distal end. Pro- and meta- tibiae visible but not well preserved. Scutellum moderately large, triangular. Elytra very short, emarginate along lateral margin and probably along suture. Lateral margin of elytral apices widely divergent. Elytra with numerous large tubercles and punctures on apical fourth. Metathoracic wings large, well-developed. Venation similar to that of other Phyllobaeninae examined. Anal veins completely reduced. Abdomen broad, at least four segments exposed by truncate elytra, not otherwise distinctive. Length of specimen examined 5.4 mm. Materials: The holotype of this species was apparently in Wickham s personal collection but could not be located by me. An additional specimen of this species is present in the collection of the Museum of Comparative Zoology which was identified as Hydnocera wolcotti by Wickham. I have examined this specimen and have illustrated it here (Figure 1). Discussion of New Status: The genus Hydnocera Newman was synonymized with the genus Phyllobaenus by Wolcott (1944: ). However, Hydnocera wolcotti Wickham was not assigned to any extant genus by Wolcott (1947), Corporaal (1950) or Barr (1976). Of the three species of Hydnocera which Wickham compared with Hydnocera wolcotti, one (Hydnocera pubescens (LeConte)) is currently placed in the genus Phyllobaenus, while two (Hydnocera curtipennis Newman (=longicollis Ziegler) and Hydnocera tabida LeConte) are currently placed in the genus Isohydnocera Chapin. The character usually used to separate Phyllobaenus and Isohydnocera is the structure of the tarsal claws (see Knull 1951:278), but these genera can also be accurately differentiated on a gross morphological level. Since the tarsi of Hydnocera wolcotti Wickham are not preserved, assignment of this species to any extant genus must be done on the basis of gross morphological similarity. Hydnocera wolcotti Wickham shares several features with each of several extant genera and thus cannot be properly placed into

4 132 Psyche [Vol. 99 Figure 1: Miohydnocera wolcotti (Wickham). Length from frons to end of abdomen 5.4 mm. one of these genera. The pronotum and scutellum of Hydnocera wolcotti Wickham are very similar to those of species of the genus Phyllobaenus such as Phyllobaenus subaeneus (Spinola), Phyllobaenus lecontei (Wolcott) or Phyllobaenus unifasciatus (Say). of Hydnocera The size and placement of the eyes (see Figure 1) wolcotti and the overall shape of the elytra and abdomen are similar to those of species of the genus Isohydnocera such as Isohydnocera curtipennis (Newman). Short elytra such as those of Hydnocera wolcotti Wickham are found in the genera Phyllobaenus, Isohydnocera, and Wolcottia Chapin. However, characters such as the dilated femora, the shape of the eyes, the pattern of

5 1992] Mawdsley--Cleridae 133 punctures and tubercles on the elytra, and the extreme shortness of the elytra appear to be unique to Hydnocera wolcotti. Since Hydnocera wolcotti Wickham cannot be placed into any known genus of the subfamily Phyllobaeninae, a new genus (Miohydnocera) is created for its reception. Subfamily CLERINAE Thanasimus florissantensis (Wickham) NEW COMBINATION Reference: Wickham 1914:448. Original Description: "Form moderately elongate. Head large, as wide as the pronotum, sculpture nearly efficed but what remains indicates it to have consisted of a fine punctuation. Prothorax broader at apex than at base, widest well in front of the middle, sides, judging by the better preserved one, gently arcuate, base with a fairly well-defined collar or constriction, surface with poorly defined punctuation and with traces of hairs. Elytra narrow in the humeral region, humeri rounded, surface obscurely punctate and hairy with a few traces of fine lineation, apices broken off. Legs only fairly stout. Length of fragment, 9mm; in life, probably about.75 mm more" (Wickham 1914:448). Redescription: Head large, nearly as wide as pronotum. Eyes large, antennae inserted in the ocular notch. Pronotal sides subparallel, pronotum proper slightly expanded. Subapical depression present, close to apex, pronotal arch correspondingly much reduced. Pronotum proper with a longitudinal median depression. Prebasal collar concave, well-defined. Scutellum small, triangular. Pro- and meso- femora slightly shorter than metafemora. Mesotibiae slightly expanded distally. Mesotarsi visible but not particularly well preserved. Elytra elongate, parallel-sided. Humeri angulate, elytra emarginate along lateral margin. Elytra with indistinct striae on basal half. Fossil slab broken off approximately 2-3 mm from elytral apices. Length of fragment preserved: 9.4 mm. Materials: Known from the HOLOTYPE in the collection of the Museum of Comparative Zoology, illustrated as Figure 2. Discussion of New Status" Wickham initially described this species as a member of the genus Enoclerus Gahan. However, this species has both striate elytra and a longitudinal median pronotal depression, characters which are never found in species of the

6 134 Psyche [Vol. 99 Figure 2. Thanasimus florissantensis (Wickham) HOLOTYPE. Length of specimen preserved 9.4 mm.

7 1992] Mawdsley--Cleridae 135 genus Enoclerus but which are characteristics of the genus Thanasimus Latreille. Therefore, I have transferred Enoclerus florissantensis to the genus Thanasimus. Note: This is perhaps the most difficult of the Florissant Cleridae to study. The above redescription and illustration were produced after lengthy study of the fossil. Wickham did not devote considerable amounts of time to examining and describing each fossil species, as he was primarily interested in gaining a general overview of the proportionate representation of each coleopterous family (Wickham 1914:423). The discrepancies between the original description and the redescription are the product of Wickham s cursory examination of the specimen prior to description. Subfamily EPIPHLOEINAE Epiphloeus pristinus (Wickham) NEW COMBINATION Reference: Wickham 1914:449. Original Description: "Form moderately elongate, subparallel, head large, apparently greater in size than prothorax, minutely scabrous and with a few rather long blackish hairs, probably the remains of a much more thickly disposed vestiture. Eyes of good size. Only one antennae is shown, and that in poor preservation, but the external joints are seen to be moderately thickened forming a gradual club. Prothorax strongly transverse, not very much narrowed posteriorly, sides feebly arcuate, anterior impressed line distinct. The sculpture is poorly preserved but what remains indicates a fine reticulation or scabrosity. Elytra a little more than twice the combined length of the head and prothorax, apices bluntly rounded, sculpture obscure but traces are to be seen of vague sulcations or costae. Legs not very long and rather slender. Length as preserved, 8.15 mm; to elytral apices, 6.85 mm" (Wickham 1914:449). Redescription: Head large, badly damaged. Frons with scattered setae and punctures. Right eye clearly visible, only slightly indented along the interior margin, not deeply emarginate. Antennae with terminal segments forming a slight club. Pronotum transverse, parallel-sided, with a shallow apical depression. Scutellum small, triangular. Elytra elongate, more or less parallel sided, emarginate along lateral edge, with a few scattered irregular

8 136 Psyche [Vol. 99 Figure 3" 6.85 mm. Epiphloeus pristinus (Wickham) HOLOTYPE. Length of specimen

9 1992] MawdsleymCle ridae 137 punctures. Legs elongate, slender. Metatarsi with heart-shaped pulvilli on at least two segments. Abdomen badly damaged, finer structure not resolvable. Materials: Known from the HOLOTYPE in the collection of Museum of Comparative Zoology, illustrated as Figure 3. Discussion of New Status: This species was placed by Wickham in the genus Enoclerus. However, the structure of the eyes clearly places this species in the subfamily Epiphloeninae. Only two genera of Epiphloeinae (Phlogistosternus Wolcott and Neichnea Wolcott) are currently found in North America. Enoclerus pristinus Wickham does not resemble present-day species of either of these two genera, as it is much larger and has sparse, irregular elytral punctures. However, the large size and irregular elytral punctures are typical of species of the genus Epiphloeus Spinola, and it is therefore to this genus that I assign Enoclerus pristinus. The genus Epiphloeus contains thirty-seven extant species, found from Mexico to northern Brazil (Corporaal 1950:255). Subfamily KORYNETINAE Necrobia divinatoria Wickham Original Description" "Preserved in ventral view and showing scarcely any sculptural characters except those of the under surface. Outline similar to that of the recent N. rufipes. Antennae with a three-jointed club, similar to that of recent North American species but with the two joints preceding a little larger in the fossil. Under surface of meso- and metathorax with shallow, rather fine punctures, visible only in certain lights, abdominal segments more finely punctulate and with short hairs. Legs wanting. Length as preserved, to tip of abdomen, 7 mm, in life somewhat less since the body is abnormally distended" (Wickham 1914: ). Addenda: The antennal structure is not nearly as clear as indicated by Wickham. This species is, as Wickham indicated, fairly similar in appearance to the modern-day species Necrobia rufipes (de Geer). Materials: Known only from the HOLOTYPE in the collection of the Museum of Comparative Zoology, illustrated as Figure 4.

10 138 Psyche [Vol. 99 Figure 4: Necrobia divinatoria Wickham. HOLOTYPE. Length of specimen 7.0 mm

11 1992] Mawdsley--Cleridae 139 SUMMARY The four known species of Cleridae from the Upper Miocene of Florissant, Colorado are redescribed and illustrated. A new genus, Miohydnocera, is created for Hydnocera wolcotti Wickham. Two species, Enoclerus florissantensis Wickham and Enoclerus pristinus Wickham, are respectively transferred to the genera Thanasimus and Epiphloeus, NEW COMBINATIONS. Necrobia divinatoria Wickham is also treated. LITERATURE CITED BARR, W. F Family Cleridae. North American Beetle Fauna Project 4:73: CORPORAAL, J. B Coleopterorum Catalogus Supplementa Pars 23 Editio Secunda Cleridae. W. Junk, Netherlands. 373 pp. EKIS, G Classification, Phylogeny, and Zoogeography of the Genus Perilypus (Coleoptera: Cleridae). Smithsonian Contributions to Zoology 227: i-iv KNULL, J. N The Checkered Beetles of Ohio (Coleoptera: Cleridae). Ohio Biological Survey 42: WICKHAM, H. F Fossil Coleoptera From the Wilson Ranch near Florissant, Colorado. Bulletin of the State University of Iowa 57: plates New Miocene Coleoptera From Florissant. Bulletin of the Museum of Comparative Zoology 58:11: plates. WOLCOTT, A. B A Generic Review of the Subfamily Phyllobaeninae. Journal of the New York EntomologiCal Society 7:2: Catalogue of North American Beetles of the Family Cleridae. Fieldiana: Zoology 32:2:

12 Correction to" N. Virkki, J. A. Santiago-Blay, and S. M. Clark Psyche 98(4)" 385

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