A new key is presented to separate adults of the four currently-recognized species of the genus Cradytes Casey (Insecta: Coleoptera: Melyridae): C. longicollis Casey, C. serricollis (LeConte), C. serrulatus . (LeConte), and C. ursinus Blaisdell. The inaccurate statements in an earlier key to species of Cradytes are discussed

Mawdsley, Jonathan R.

English

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INSECTA MUNDI, Vol. 15, No.3, September, 2001  181 A new key to the species of the genus Cradytes Casey (Insecta: Coleoptera: Melyridae) Jonathan R. Mawdsley Department of Entomology, MRC 187 National Museum of Natural History Smithsonian Institution Washington, DC 20560-0187 USA Abstract: A new key is presented to separate adults of the four currently-recognized species of the genus Cradytes Casey (Insecta: Coleoptera: Melyridae): C.  longicollis Casey, C.  serricollis (LeConte), C.  serrulatus . (LeConte), and C.  ursinus Blaisdell.  The inaccurate statements in an earlier key to species of Cradytes are discussed. Introduction The genus Cradytes Casey contains the largest North American species in the subfamily Dasyti-nae of the beetle family Melyridae.  Adults of C. serricollis (LeConte) are common to abundant on flowers in dry grasslands throughout much of  west-ern North America, while adults of C.  longicollis Casey,  C.  serrulatus  (LeConte)  and  C.  ursinus Blaisdell  are found  on  flowers  in  southeastern Arizona.  The taxonomy of Cradytes was last re-viewed by Blaisdell (1924), who provided a key to the four species of this genus that relied primarily on characters of elytral pigmentation and colora-tion of the elytral vestiture. I recently had the opportunity to study a large collection of Cradytes species in the collection of  the National Museum of Natural History, Smithsonian Institution (NMNH).  These studies have revealed problems with several of the characters chosen by Blaisdell  (1924)  to  separate  the  species  of this genus.  Although four distinct species of Cradytes do occur in America north of Mexico, these species cannot be accurately separated using Blaisdell's key.  Individuals of C.  serricollis with uniformly black elytral pigmentation will run to C. ursinus in this key.  The legs of specimens of C. serrulatus are shades of reddish-brown, not black as was errone-ously stated in Blaisdell's key.  And the statement in Blaisdell's key that the erect elytral setae of C. longicollis are pale (rather than black) is mislead-ing, since all of the specimens of this species that I have  examined have  at least some  black  erect elytral  setae,  and in some  specimens  there  are numerous  erect black  setae.  To  facilitate  the identification of these large, common melyrids, I have provided a new, corrected key to the species of the genus Cradytes below. Cradytes Casey Cradytes  Casey  (1895:458,  533-536),  Blaisdell (1924:336-337; 1938:8, 21). Trichochrous Motschulsky, subgenus Cradytes Ca-sey, Pic (1937:90). Type Species: Pristoscelis serricollis LeConte (designation by Blaisdell 1938:21). Diagnosis: Cradytes belongs to a group of gen-era ofDasytinae in which one ofthe two spurs ofthe protibiae and mesotibiae in the male is strongly curved, enlarged, and more or less spatulate; the remaining tibial spur is a short unmodified spine. Trichochrous  Motschulsky is  probably the  most familiar genus in this group.  From related genera, Cradytes can be easily recognized by the strongly serrate lateral margins of the pronotum and by the comparatively large body size of its species.  The serrations ofthe lateral pronotal margin are partic-ularly well developed towards the anterior end of the prothorax.  Keys to genera of Nearctic Dasyti-nae by Blaisdell (1938) and Arnett (1968) will help to separate adults of Cradytes species from related genera. Key to Species of Cradytes Casey 1.  Legs dark brownish-black to black; body elongate and slender, especially the pronotum in male; width of elytra across humeri 1.1-1.4 mm; elytra dark brown or black, never with yellow pigmen-tation ................................. C.  longicollis Casey Legs bright reddish-orange or red, at least in part; body stout, robust; width of elytra across hu-meri 1.5 mm or greater (often 2.0 mm or great-er);  elytra  with  yellow  pigmentation in  one species ................................................................ 2 182  Volume 15, No.3, September, 2001, INSECTA MUNDI 2. 3. Elytral and pro  notal vestiture sparse, punctures and surface of elytra easily visible; elytra al-ways black ......................................................... 3 Elytral and pro  notal vestiture dense, punctures and surface of elytra not easily visible; elytra often yellow, at least in part ............................ . ...................................... C.  serricollis (LeConte) Reclinate portion of elytral vestiture very short (0.2-0.4 mm); femora darker in color than tibi-ae; body slightly smaller in size, overall length 3.9-4.0 mm, width across humeri 1.6-1.7 mm. ...................................... C.  serrulatus (LeConte) Reclinate  portion  of elytral vestiture  elongate (0.4-0.7 mm); femora and tibiae both reddish-orange;  body  slightly  larger in  size,  overall length 4.3-6.0 mm, width across humeri 1.75-2.4 mm ............................... C.  ursinus Blaisdell Cradytes longicollis Casey Cradytes  longicollis  Casey  (1895:533-535),  Blaisdell (1924:337) (HOLOTYPE male, and 8 PARATYPES, 5 male, 3 female, labeled "Ari", NMNH type 37367, examined). Trichochrous longicollis  (Casey), Pic (1937:94). Diagnosis: The elongate, slender body (especially the elongate, slender pronotum of the male) will readily separate this species from other species of Cradytes. Additional specimens examined: Mexico: Sono-ra: Nogales, 3.VIII.1940, on cut flowers (1, NMNH), 17.IX.1940  (1,  NMNH),  28.IX.1940  (1,  NMNH), 3.X.1941  (1,  NMNH).  USA:  Arizona:  Douglas, 20.IX.1944  (6,  NMNH);  Nogales,  26.IX.1946,  on Aster tanacetifolius (5, NMNH). New Mexico: Luna (2, NMNH); 2 miles NE Santa Rosa, 7.IX.1929, on Salsola pestifer (1,  NMNH). Cradytes serricollis (LeConte) Pristoscelis  serricollis LeConte  (1866:356)  (Two  SYN-TYPE males, labeled "Col" and "NM", MCZC type 3508, examined). Cradytes serricollis (LeConte), Casey (1895:534), Blais-dell (1924:337), Mawdsley (1999:253, 257-258). Trichochrous serricollis (LeConte), Pic (1937:95). Diagnosis: Most specimens of this species can be readily identified by the presence of  yellow pigmen-tation on the elytra.  The elytra may be entirely yellow, yellow with a black or brown basal macula-tion, yellow with brown or black vittae, brown or black with yellow vittae, or entirely black.  Speci-mens with the elytra entirely black may be con-fused  with  C.  ursinus,  but in that species  the vestiture of  the pronotum and elytra is much spars-er  . Notes: It  is clear from my examinations of numer-ous additional specimens that this species is ex-tremely variable in its elytral coloration. Blaisdell (1924) states that C. serricollis can be distinguished from the remaining species of Cradytes by its yel-low elytra; the elytra of other species are said to be entirely black. However, specimens of C. serricollis collected in southeastern Arizona, western Texas, and  southern  New  Mexico  frequently  have  the elytra partly or entirely brownish-black, and some specimens from these states have the elytra entire-ly black. Specimens of the latter  form are similar in appearance to the sympatric C.  ursinus. Additional specimens examined: Mexico: Sono-ra: Nogales, 28.IX.1940, on cut flowers (1, NMNH). USA: Arizona: Cochise Co., Bisbee, 28.IX.1981, on wild cotton (3,  NMNH), Douglas, 17.IX.1944 (11, NMNH),  9.IX.1956  (1,  NMNH),  7.IX.1957  (2, NMNH), Dos Cabezas, 6.IX.1969 (1, NMNH), Por-tal, 3.IX.1957 (12, NMNH)  , 5.IX.1947 (5, NMNH), 6.IX.1957 (1, NMNH), 3 miles S Portal, 11.IX.1957 (3, NMNH); Coconino Co., Moenkopi Wash, 2 miles SE Tuba City, 31.VIII.1986 (2, NMNH); Navajo Co., Dinnebito  Wash, 5 miles NW Hotevilla, 31.VIII.1986 (7,  NMNH),  Winslow  (2,  NMNH),  12.IX.?  (1, NMNH); Santa Cruz Co.,  Nogales,  30.V.1919 (4, NMNH),  26.IX.1946  (4,  NMNH),  Pen  a  Blanca, 11.X.1971 (4, NMNH), San Rafael Valley, 3.X.1971 (2,  NMNH)  ,  Tubac,  15.IX.1970  (2,  NMNH);  no locality specified (3,  NMNH).  Colorado:  Denver Co.,  Denver  (71,  NMNH),  5.IX.?  (12,  NMNH), ?VIII.?  (1,  NMNH);  Las Animas  Co.,  Trinidad, 12.IX.1898  (4,  NMNH);  Weld  Co.,  near  Carr, 11.IX.1975  (14,  NMNH),  Nunn,  Pawnee  Grass-land, Pasture 31, 21.IX.1972, feeding on stems of Chrysothamnus  nauseosus  (1,  NMNH),  Pasture YP-1, 19.VIII.1972 (1, NMNH); no locality specified (9,  NMNH).  Additional  Colorado  localities  are given by Mawdsley (1999). New Mexico: Colfax Co., Koehler,  prairie  near,  (6,  NMNH),  ?VIII.?  (3, NMNH), ?.IX.? (3, NMNH); Eddy Co., Whites City, 27.IX.1971  (12,  NMNH);  Hidalgo  Co.,  Rodeo, 3.IX.1957 (1,  NMNH),  11.IX.1957 (3,  NMNH),  4 miles S Rodeo, 18.IX.1957 (1,  NMNH), 23.IX.1957 (3,  NMNH), 25.IX.1957 (7,  NMNH)  , 6 miles S Ro-INSECTA MUNDI, Vol. 15, No.3, September, 2001  183 deo, 28.IX.1957 (1, NMNH); no locality specified (1, NMNH).  Texas: Presidio Co., Presidio, 4.X.1945, on flowers Viguiera stenoloba (1, NMNH), 8.X.1947 (91,  NMNH),  27.X.1948  (6,  NMNH)  ,  on  flowers Bahia pedata,  3.X.1947  (7,  NMNH),  on flowers Haplopappus  sp.,  6.X.1948  (1,  NMNH).  Utah: Uintah Co., Fort Duchesne, 3.IX.1937 (1,  NMNH). Wyoming:  Campbell  Co.,  40  miles  S  Gillette, 14.VIII.1961  (8,  NMNH);  Carbon  Co.,  Medicine Bow,  20.VIII.1934 (1,  NMNH); Niobrara Co.,  Old Woman  Creek,  23.VIII.1915  (1,  NMNH);  Platte Co.,  Wheatland,  Laramie  River,  9.IX.1974  (10, NMNH); "Western Wyoming" (1, NMNH); no local-ity specified (1,  NMNH).  Question mark (?) indi-cates data missing from original label. Cradytes serrulatus (LeConte) Pristoscelis serrulatus LeConte (1866:356) (HOLOTYPE female,  labeled  "Ariz.",  MCZC  type  3509,  exam-ined). Cradytes  serrulatus  (LeConte),  Casey  (1895:535-536), Blaisdell (1924:337). Trichochrous serrulatus (LeConte), Pic (1937:96). Diagnosis: The short and sparse reclinate setae on the elytra of this species will readily separate it from other species of Cradytes, in which the recli-nate elytral setae are much longer. Notes: Blaisdell (1924) states that the legs of this species are black.  However, in both the holotype and the second specimen examined, the legs are reddish-brown with the femora brownish. Additional specimens examined: USA: Arizo-na: no locality specified (1,  NMNH). Cradytes ursinus Blaisdell Cradytes ursinus Blaisdell (1924:336-337) (HOLOTYPE male and ALLOTYPE female plus one PARATYPE, sex not determined, AZ:  Nogales, 4.IX.1906, CASC type 2718; types not examined). Trichochrous ursinus (Blaisdell), Pic (1937:97). Diagnosis: This species is easily confused with melanic individuals of C. serricollis, which have the elytral setae much denser.  Cradytes serrulatus is also similar in general body form, but adults ofthat species are slightly smaller and their elytral setae are significantly shorter, as described in the key. Notes: My concept of this species is based on the two additional specimens listed below, which were labeled C.  ursinus in the NMNH collection.  These specimens conform closely to the detailed descrip-tion of C.  ursinus provided by Blaisdell (1924) and represent a species of Cradytes that  is distinct in its external  anatomy from  the  three  other  species discussed above. Additional specimens examined: USA:  Arizo-na: Cochise Co., Cochise Stronghold, 22.IX.1971 (1, NMNH); Santa Cruz Co., Pena Blanca, 10.IX.1970 (1,  NMNH). Acknow  ledgments Support  for the author was provided by a Smith-sonian Institution Postdoctoral Research Fellow-ship, sponsored by Terry L. Erwin. Gloria House of the Smithsonian Institution provided valuable as-sistance by providing access to the collections of Melyridae  in  the  National Museum  of  Natural History (NMNH).  David G.  Furth and Philip D. Perkins assisted with the examination of melyrid type specimens in the collection of the Museum of Comparative  Zoology  at  Harvard  University (MCZC).  Charles L. Staines and Warren E. Stein-er, Jr., provided valuable comments on the manu-script prior to submission. Literature cited Arnett, R. H., Jr. 1968. The beetles of the United States (a manual for identification). Ann Arbor: American Entomological Institute. xii + 1112 pp. Blaisdell, F. E. 1924.  Studies in the Melyridae (Coleoptera) number two. Transactions of the American Entomological Society 49: 315-337. Blaisdell,  F.  E.  1938.  A  generic  synopsis  and generic revision of the tribe Dasytini of North America north of Panama (Coleoptera: Melyr-idae).  Transactions of the American Entomo-logical Society 64: 1-31 + pIs. 1-2. Casey, T. L. 1895.  Coleopterological notices VI. Annals of  the New York Academy of Sciences 8: 435-838. LeConte, J. L. 1866. Revision of  the Dasytini ofthe United States. Proceedings of the Academy of Natural Sciences, Philadelphia 19: 349-361. 184  Volume 15, No.3, September, 2001, INSECTA MUNDI Mawdsley, J. R.  1999. Review of the extant and fossil Dasytinae (Coleoptera: Melyridae) of Col-orado, U. S. A.  Transactions of the American Entomological Society 125(3): 251-267. Pic,  M.  1937.  Dasytidae:  Dasytinae.  Coleopter-orum Catalogus 155: 1-130. 

A new key to the species of the genus Cradytes Casey (Insecta: Coleoptera: Melyridae)

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