Procas Stephens, 1831

Thompson, Richard T., 2006, A revision of the weevil genus Procas Stephens (Coleoptera: Curculionoidea: Erirhinidae), Zootaxa 1234 (1), pp. 1-63 : 9-11

Procas Stephens, 1831

Genus 297: Stephens 1829b: 167.

Procas Stephens, 1831: 90, 1839: 213 ; Curtis 1837: 63 [= Hypera ]; Westwood 1838: 36; Schönherr 1842: 386; Calwer 1858: 513; Redtenbacher 1858: cxx, 731, 1874: cxxv, (2)270; Bose 1859: 493; Chenu & Desmarest 1860: 226 [erratim Phocas]; Lacordaire 1863: 467; Gemminger & Harold 1871: 2433; Tournier 1874: 68, 70; Seidlitz 1875: 119 (note), 1891: 162; LeConte & Horn 1876: 162, 1883: 473; Pascoe 1882: 21: Bargagli 1884: 206: Stierlin 1893: 470; Desbrochers 1894: 82; Kuhnt 1912: 914; Reitter 1912: 75, 1916: 196, 204; Blatchley & Leng 1916; 193, 200; Wagner 1916: 1097, 1099; Hustache 1930: 136, 140; Scheerpeltz & Winkler 1930: 251; Joy 1932: 225, 230; Klima 1934: 29; Reinkardt 1948: 574; Hoffmann 1958: 1419; Kissinger 1964: 14, 45; Sebö 1971: 4, 45; Pesarini 1978: 2; Angelov 1980: 267; Lohse 1983: 59, 68; Caldara & O’Brien 1995: 393, 403, fig. 19; Zherikhin, Egorov & Gratzev 1996: 258; Egorov, Zherikhin & Korotyaev 1996: 437; Alonso­Zarazaga & Lyal 1999: 70; Hong, et al. 2000: 17; Morris 2002: 36; Anderson 2002: 731; Morris 2003: 200.

Type species: Curculio picipes Marsham, 1802 designated by Westwood (1838).

Derivation of the name

Stephens has ‘nomen viri’ but according to Wright (1949) Procas was ‘A king of Alba [Longa], a city of Latium (a country of Italy, near the river Tiber) destroyed by the Romans 637–640 B.C.’

Diagnosis

Medium­sized (3–8 mm) erirhinid Curculionoidea with exposed surfaces of head, thorax, legs and venter covered with very dense punctures, their interspaces sometimes forming a reticulate pattern, especially on pronotum; elytral striae deep, sharply defined, catenulately punctured ( Figs 2–8 ), interstriae finely granulate; head, body and elytra black, antennae and tarsi dark brown to reddish brown, femora and tibiae usually black but sometimes brown. Fully winged.

Vestiture of body composed solely of blackish brown and white setae; the latter may be either fairly evenly distributed, segregated to form a variegated pattern or condensed to form white spots; middle and hind tibiae with dense mass of very fine, elongate brownish white setae in apical third, or more, of their length and, often, with a circlet of white setae at base.

Head globose, sometimes with a small frontal pit; eyes ovate, weakly convex; rostrum strongly curved, × 3.7–5.1 as long as broad and × 0.9–1.25 as long as pronotum, sides straight or weakly sinuous, widening distinctly, and usually rather abruptly, around preapical antennal insertions; mandibles porrect, blade­like, with two large teeth on mesal aspect.

Antennae ( Figs 18–20 ) with 2(–3) basal funicle segments elongate, segments (3–) 4­7 quadrate (7 sometimes transverse).

Prothorax much narrower than elytra ( Fig. 1 ), × 0.75–0.95 as long as broad, subglobose, with weak post­ocular lobes.

Scutellum small, isodiametric, convex.

Elytra about × 1.48 as long as broad; sides, in basal half, straight, parallel or weakly diverging posteriad ( Figs 2–8 ), shoulders well developed, apex broadly rounded.

Legs with femora unarmed, isometric; tibiae distinctly mucronate, tibial spur formula 2­2­2; tarsi with segment 3 broad, strongly bilobed, segments 1–3 with dense setae beneath.

Venter with disc of ventrites 1 and 2 weakly to distinctly depressed in male, flat or weakly depressed in female.

Terminalia. Male: median lobe of aedeagus simple (tectum obsolete); internal sac without any large sclerites, extending anteriad to, or somewhat beyond, tips of apodemes ( Fig. 15 ); dorsal plate of tegmen bilobed both posteriorly and, to a lesser extent, anteriorly; manubrium large, straight ( Fig. 15 ); spiculum gastrale small, curved, forked posteriorly ( Fig. 15 ); sternite 8 reduced to pair of small crescent­shaped hemisternites and a median unsclerotized column bearing a pair of elongate processes; hemisternites with simple setae, irregularly arranged ( Figs 74–99 ). Female: ovipositor transverse, with strongly pigmented barrel­shaped styli ( Fig. 17 ); bursa simple, membranous; spermatheca with distinct gland­lobe and long duct, inserted at base of oviduct ( Fig. 16 ); sternite 8 broad, pigmented at sides, setose at apex, with slender spiculum ( Figs 21–43 ).

Comments

The rostrum exhibits weak positive allometry in all the species. The surface puncturation extends, unusually, to the secondary scrobes but the inner (posterior) faces of the hind femora are smooth and polished (only clearly seen when femur is detached). Almost all of the clothing setae are simple but bifid or sometimes multifid setae occur on the sides of the prothorax, on the meso­ and metepisterna and at the sides of ventrite 1 in most of the species. Low median carinae are often present on the rostrum and pronotum but are neither constant nor complete in any of the species.

The European species of Procas resemble one another very closely and each varies widely in size and, sometimes, in details of its clothing setae. This led Bedel (1879) to synonymize picipes , steveni and cottyi under armillatus ; the first two species have remained in synonymy but cottyi , which really is a synonym of armillatus , was revived as a valid species by Winkler (1932). The status of granulicollis has hitherto been uncertain; it is usually cited as another synonym of armillatus ( Klima 1934) .

As a result of this study, I am able to recognize six species of Procas , one of which has three subspecies (including the nominate) thus:

granulicollis Walton, 1848

picipes ( Marsham, 1802)

p. picipes ( Marsham, 1802)

moestus ( Bach, 1854)

minutus Desbrochers, 1893

p. steveni ( Gyllenhal, 1835)

p. levantinus ssp. n.

michaelis sp. n.

armillatus ( Fabricius, 1801)

atomarius ( Gené, 1839)

cottyi Perris, 1864

biguttatus Faust, 1882

okunii Kôno, 1930

lecontei Bedel, 1879

picipes LeConte & Horn, 1876 , not ( Marsham, 1802)

Since Curculio picipes Marsham, 1802 is a junior primary homonym of Curculio picipes Linnaeus, 1767 (= Otiorhynchus singularis (Linnaeus)) , I ( Thompson 2003) asked the International Commission on Zoological Nomenclature to validate Marsham’s name under Article 23.9.5 of the Code and the Commission duly ruled in my favour ( International Commission on Zoological Nomenclature 2005).

External characters for separating the species are not altogether reliable and some are difficult to see or interpret. Similar problems have been encountered with the traditional internal structures (aedeagus, spiculum ventrale). The spermatheca is better, if studied carefully, but the best structure by far is sternite 8 of the male. This has been used effectively among Curculionoidea at family­group level ( Thompson 1992) and among Erirhinidae at generic level ( Thompson 2005). All characters vary and this variation should, ideally, be studied throughout the range of each species. For this reason, I have included additional figures, where possible, to support my decisions.

Figures

FIGURES 1–8. 1. Habitus, dorsal, of Procas picipes levantinus; 2–8. Elytra, dorsal, of (2) P. p. levantinus, (3) P. granulicollis (normal form), (4) ditto (‘shaggy’ form), (5) P. p. picipes, (6) P. lecontei, (7) P. armillatus, (8) P. biguttatus.

FIGURES 15–20. Terminalia of (15) Procas granulicollis, male, ventral view, (16) P. p. picipes, female, dorsal view (right valve of ovipositor omitted). Scale­bar = 0.5 mm. Key: bc, bursa copulatrix; is, internal sac; m, manubrium; od, oviduct; op, ovipositor; s, sternite 8; sg, spiculum gastrale; sv, spiculum ventrale; t, tegmen (apex of dorsal plate). Ovipositor of P. p. picipes (17). Scale­bar = 0.1 mm. Antennae, ventral view, of (18) P. armillatus, (19) P. lecontei, (20) P. granulicollis. Scale as figs 15, 16.

FIGURES 74–85. Sternite 8 of male of Procas p. picipes from (74, 75) England, Brighton, (76) France, Marseille, (77) Italy, Lucera, (78) Italy, Mastro Marco; P. p. steveni from (79, 80) Azerbaijan, (81) Ukraine, Odessa; P. p. levantinus from (82) Israel, Jerusalem; P. granulicollis from (83, 84) Wales, (85) Spain. Scale­bar = 0.2 mm.

FIGURES 86–99. Sternite 8 of male of Procas michaelis from (86) Spain, Santa Lucia, (87) Spain, Tablas de Daimiel; P. armillatus from (88) Corsica, Bonifacio, (89) Algeria, Oran, (90) Libya, Benghazi, (91) Azores, São Miguel I, Livramento; P. biguttatus from (92) Russian Far East, Evseevka, (93) China, ‘Erdzendjancy,’ (94) Russian Far East, Vladivostok, (95) Japan, Hokkaido; P. lecontei from (96) Canada, Yukon, Dawson, (97) USA, Colorado, La Vita Pass, (98) Canada, Quebec, Duparquet, (99) Canada, Ontario, Pearson Point. Scale­bar = 0.2 mm.

FIGURES 21–26. Sternite 8 of female of (21) Procas granulicollis, ‘shaggy’ form from Spain, Cancas, (22) normal form from Wales, Carn Gefalt, (23) ditto, from Spain; (24) P. picipes levantinus from Israel, Jerusalem, (25) ditto from Jordan, Amman; (26) P. michaelis from Spain, Puente. Scale­bar = 0.2 mm.

FIGURES 27–34. Sternite 8 of female of Procas p. picipes from (27, 28) England, Brighton, (29) France, Marseille, (30) Spain, Barcelona, (31) Germany, Duben; P. p. steveni from (32) Russia, Rostov, (33) Caucasus, (34) Azerbaijan. Scale­bar = 0.2 mm.

FIGURES 35–38. Sternite 8 of female of Procas armillatus from (35) Canary Is, (36) Algeria, (37) Tunisia, Teboursouk, (38) Algeria, Setif. Scale­bar = 0.2 mm.

FIGURES 39–43. Sternite 8 of female of Procas biguttatus from (39) Russian Far East, Bikin River, (40) Russian Far East, Evseevka; P. lecontei from (41) USA, Colorado, La Vita Pass, (42) Canada, Quebec, Duparquet, (43) Canada, North West Territories, Lake Exmouth. Scale­bar = 0.2 mm.