Laemosaccus clytrinoides Hespenheide, 2019

Hespenheide, Henry A., 2019, A Review of the Genus Laemosaccus Schönherr, 1826 (Coleoptera: Curculionidae: Mesoptiliinae) from Baja California and America North of Mexico: Diversity and Mimicry, The Coleopterists Bulletin (MIMICRY AND LAEMOSACCUS In an earlier paper (Hespenheide 1996), I presented the hypothesis that species of Laemosaccus of the L. nephele group with red humeral spots on the elytra were Batesian mimics of members of the Chrysomelidae in the subfamily Clytrinae. There is no evidence that Laemosaccus species are distasteful, and what is either L. nephele and / or L. obrieni have been reported as prey items of birds (Beal 1912). In Cave Creek Canyon, Cochise County, Arizona, 21 forms (species and “ subspecies ”) of Clytrinae were hypothesized to be the primary models of 22 species of mimics in the families Anthribidae (one species), Bruchidae (two species), Buprestidae (four species), Chrysomelidae, subfamily Cryptocephalinae (three species), Coccinellidae (six species), Curculionidae, subfamily Baridinae (one species), and Laemosaccus (five species). Of these, the coccinellids and the cryptocephaline chrysomelids are probably distasteful Mullerian co-mimics. Ecologically, the species of Laemosaccus co-occurred with their clytrine models on both desert legumes and canyon oaks, although more clytrine species occurred in the desert and more Laemosaccus species occurred in the canyons. Species of clytrines showing the mimetic pattern are common throughout Mexico (Bellamy 2003, who renamed the Mexican buprestid genus Acherusia Laporte and Gory, 1837 as Mimicoclytrina Bellamy to reflect their resemblance to clytrines), but decline in numbers of species and in the proportion of the clytrine fauna through Central America to Panama (Hespenheide 1996, fig. 2). Laemosaccus seems to follow a similar pattern. Mimicry is more common in large faunas, especially in wet tropical areas (Hespenheide 1986, 1995); because the largest clytrine fauna is in Mexico, the clytrine mimicry complex is also larger there (Hespenheide 1996). This complex has more members than I first enumerated and deserves further study. The evolution of mimicry produces resemblances between unrelated species (Laemosaccus and other putative mimics, with clytrines and perhaps other Chrysomelidae and Coccinellidae as models; see Hespenheide 1976, 1996) and selects against the divergence of related species. In Batesian mimicry - hypothesized to be the form of relationship between Laemosaccus and clytrines - the selection for precision of mimicry is stronger on the mimic (Laemosaccus), so that resemblances among them should be closer, regardless of ancestry. Close morphological resemblances based on ecology rather than ancestry may be termed mimetic homoplasy (Hespenheide 2005) and can make recognition of species difficult (as in Laemosaccus) or complicate phylogenetic analyses. I have speculated (Hespenheide 1996) that the sympatric “ subspecies ” of the clytrine models (Moldenke 1970) may in fact be reproductively isolated sibling species. It will be interesting to see whether or not genomic studies show the closeness of relationships among Laemosaccus species that the morphology suggests) 73 (4), pp. 905-939 : 924-927

Laemosaccus clytrinoides Hespenheide , new species

Zoobank.org/ urn:lsid:zoobank.org:act:4CE73F2F-92B8-4C30-8603-C0E39211364F ( Figs. 13 , 23 )

Description. Holotype Male. Length 2.65 mm, width 1.25 mm ( Fig. 13 ). Robust, subcylindrical in cross section, slightly obovate, broadly rounded behind, more narrowly so in front, black except each elytron with oval red-orange spot slightly longer than half length of elytra beginning at humerus, from near lateral margin to obliquely posteriorly to 1 st elytral interval, and broadly rounded behind; pronotum and elytra glabrous; thorax and abdomen ventrally with punctures each with a small silvery seta, head with few setae behind eyes and inconspicuous hair-like setae on sides of rostrum distal to antennal insertions, setae inconspicuous on legs, hair-like and semi-erect on tergite 8; tergite 7 with small, scale-like setae on basal margin, otherwise glabrous. Head hemispherical, 0.65 mm wide, rostrum rounded-terete, slightly humped at base in lateral view, finely punctate except for narrow raised area along midline at middle, 0.45 mm long; antennae inserted at middle. Pronotum gibbous, weakly convex in cross section at base, more strongly so in lateral view, anterior 2/3 strongly declivous, weakly constricted before anterior margin, 0.9 mm long, 1.05 mm wide, broadest at basal third, with lateral margins regularly rounded, coarsely, evenly punctate, punctures rounded and separate, without obvious medial carina. Elytra slightly wider than pronotum at base, broadest at apical 3/4, 1.75 mm long, 1.25 mm wide, elytral striae narrower than intervals, striae finely punctate, intervals rounded-angulate, interval 3 weakly toothed on middle third, interval 5 very weakly toothed on apical half. Abdominal ventrite 1 very slightly depressed in small triangle along midline at posterior margin, with less conspicuous setae. Profemora with very small, acute ventral tooth beyond middle. Genitalia as in Fig. 23 ; aedeagus 0.65 mm long.

Allotype Female. Length 2.65 mm, width 1.25 mm, as male but rostrum forming a slight angle with plane of fronst, very stout and subcylindrical, somewhat flattened dorsoventrally, finely to moderately punctate, with narrow, raised, polished area along midline on basal 2/3; abdominal ventrite 1 medially convex, sparsely setose and somewhat shiny in broad area on either side of midline; tergite 7 weakly convex, coarsely punctate, glabrous except with small, scale-like setae on basal margin at basal margin, hair-like and semi-erect on apical fourth.

Specimens Examined. Holotype: Arizona : Cochise Co., Chiricahua Mts. , E Turkey Creek, 6.5 mi. W Portal, 6400’, 31°54-55’N 109°15’W, 16.07.1981, H. A. Hespenheide, on Quercus sp. (USNM). Allotype: Same data as holotype, but 11.07.1981, Quercus (USNM) . Paratypes: USA: Arizona: Cochise Co., Chiricahua M., 29.07.1955, D. J. & J. N. Knull (1, OSU); same data as holotype, but 17.07.1981, Quercus (1, CHAH), 20.07.1981, H. A. Hespenheide, oak (1, CHAH); Cave Ck. Cyn., Chiricahua Mts., 6 mi. W Portal, 6700’, 31°55’N 109°15’W, 11, 20.07.1981, H. A. Hespenheide, Quercus (4, BMNH, CHAH); Cave Ck. Cyn., Chiricahua Mts., Herb Martyr Dam, 5800’, 31°52’N 109°14’W, 25.07.1981, H. A. Hespenheide, oak (1, CHAH); Chiricahua Mountains, Onion Saddle, 7600’, 31°56’N 109°16’W, 22.07.1981, H. A. Hespenheide, Quercus (1, CHAH), 26.06.2001, H. A. Hespenheide, on Quercus hypoleucoides (1, CHAH); Portal, 17.06.1956, H. & A. Howden, beat oak (3, CMNC); S. W. Res. Sta., Portal, 24.06.1956, H. & A. Howden, beating oak (4, CMNC), 04.07.1956, H. & A. Howden, oak (4, CMNC); Chiricahua Mountains, 2.0 mi. W Portal, 5000’, 27.07.1982, R. S. Anderson (1, CMNC); near Portal, 28.07- 07.08.1966, K. Stephan (1, FSCA); Chiricahua Mts., 9 mi. above Portal, 22.07.1975, G. H. Nelson, on Quercus hypoleucoides A. Camus (1, ASUHIC); Chir. Mts., Pridham Cn, 05.07.1976, McCleve & Daneker (2, TAMU); Chir. Mts., W Turkey Ck, 05.07.1976, McCleve & Topham (1, TAMU); Mile High Preserve, Ramsey Cyn, 12 km S Sierra Vista, 1700 m, 25.06- 6.07.1986, B. V. Brown, Malaise, oak / juniper ripar. for. (1, CMNC); Pelencillo Mtns., 33 mi. E Douglas, 17.07.1973, S. McCleve, at light (1, TAMU) Cochise Stronghold, Dragoon Mts., 22.06.[1958], C. W. & L. O’ Brien, on oak (1, ASUHIC); Sunnyside, 17.08.1940, B. E. White (1, CASC); Huachuca Mts., 1-4 km S Sunnyside Canyon, 1676m, 27.07.1989, R. S. Anderson, on Phoradendron coryae Trel. on Quercus sp. , 89-28 (2, CMNC); Huachuca Mts., vic Ramsey Vista cpgrds., 29.08.2000, J. Huether (1, CMNC); S end Huachuca Mtns., Copper Cyn., 5.08.1990, W. F. Barr, beating Quercus (1, WFBM); Huachuca Mts., Copper Cyn., 12.08.1989, W. F. Barr, on oak (1, WFBM); Huachuca Mts., 20.07.1936, J. N. Knull (1, OSU), 19.08.1950, D. J. & J. N. Knull (1, OSU), 18.07.1938, D. W. Gralk (1, SEMC); Bear Creek, Montezuma Pass, Huachuca Mts., 6.07.1956, H. & A. Howden (1, CMNC); Graham Co., Galiuro Mts., High Cr., 1660 m, [--].07.1978, S. McCleve (1, TAMU); Pima Co., 4 mi. S Arivaca, Fraguita Wash, 10.07.1977, S. McCleve, at lite (1, TAMU); Santa Cruz Co., Santa Rita Mts., 13.08.1935, F. H. Parker (1, CASC), 11.07.1949, D. J. & J. N. Knull (1, OSU); Santa Rita Mts., Madera Cyn., 25.06.1968, C. W. O’ Brien (1, ASUHIC), 11.07.1977, A. E. Lewis (2, ASUHIC); Madera Canyon, Bog Spring Camp, 4.08.1950, B. E. White (1, CASC); Madera Canyon, 1- 2.08.1988 (1, CHAH), 8.08.1970, A. J. Gilbert (1, ASUHIC); 7 mi. SW Canelo, 10.09.1965, L. & C. W. O’ Brien (1, ASUHIC); Sycamore Cyn. crest, 5700’, 29.08.1997, Wappes & Turnbow (1, JEWC); Pajarito Mts., Pena Blanca Cyn., 13.07.1970, K. Stephan (1, FSCA); Patagonia Mts., Duquesne Rd. Summit, 31.07.2005, C.W. O’ Brien, beaten oak & juniper (1, ASUHIC). Mexico: Sonora: Sierra de Ajos, Cyn. de Evans, 15.07.1970, V. Roth (1, FSCA); 5 mi. S Cananea, 1.08.1970, V. Roth (1, ASUHIC); Sierra Huachinera, 32–34 km NE Nacori Chico, 1950 m, 06– 7.08.1982, Mex.Exped. 1982, G. E. & K. E. Ball & S. McCleve, 82-10 (1, CMNC).

Hosts. Adults have been collected on Q. hypoleucoides and undetermined oaks, and on Phoradendron coryae Trel. (Santalaceae) on Quercus sp.

Etymology. This species is named for its resemblance to clytrine chrysomelids (see discussion of mimicry below).

Discussion. Laemosaccus clytrinoides is a small species similar to L. arizonensis but with a rostrum in both sexes that is sculptured and broader than deep, broadening toward the apex with a medial impunctate area, and a distinctive aedeagus. Males vary in length from 2.40 to 3.40 mm (mean = 2.84 mm, n = 33); females from 2.25 to 3.70 mm (mean = 2.93 mm, n = 25).

Figures

Figs. 13–18. Laemosaccus species, dorsal habitus. 13) L. clytrinoides; 14) L. howdenae; 15) L. rileyi; 16) L. vaurieae; 17) L. westcotti; 18) L. texanus.

Figs. 19–24. Laemosaccus species, dorsal and lateral views of aedeagus and paramere. 19) L. andersoni; 20) L. arizonensis; 21) L. bimaculatus; 22) L. burkei; 23) L. clytrinoides; 24) L. howdenae.