Psalidognathus thomsoni Lameere, 1885

Santos-Silva, Antonio & Komiya, Ziro, 2012, Contribution towards the knowledge of Psalidognathus Gray, 1831 (Coleoptera, Cerambycidae, Prioninae), Insecta Mundi 2012 (247), pp. 1-28 : 5-7

Psalidognathus thomsoni Lameere, 1885 , revalidated

( Fig. 1-7 )

Psalidognathus modestus ; Thomson 1859: 40 (male) (non Fries 1833); Lameere 1885a: 7 (larva).

Psalidognathus mygaloides ; Thomson 1877: 257 (non Thomson 1859); Thomson 1878: 4 (types).

Psalidognathus thomsoni Lameere, 1885b : ix; Blackwelder 1946: 555 (checklist); Jeniš 2010: 20, 21, 86, 87.

Psalidognathus (Psalidognathus) thomsoni ; Lameere 1910: 372; 1913: 64 (cat.); 1919: 120; Quentin and Villiers 1983: 444 (syn.; lectotype).

Psalidognathus erythrocerus reichei ; Komiya 2003: fig. 18 (male).

Redescription. Male ( Fig. 1-5 ). Integument dark-brown, almost black, with slightly violaceous reflection (mainly on basal half of elytra); antennomeres V-XI gradually lighter; apical extreme of maxillary and labial palpi and posterior edge of ventrites I-III lighter brown.

Dorsal surface of head ( Fig. 2, 5 ) strongly rugose; pilosity slightly long, sparse. Cephalic carinae ( Fig. 5 ) wide up to posterior edge of eyes; narrow from this point, not notably elevated throughout (subuniform height along the entire length); prolonged and parallel up to almost anterior margin of pronotum, with small and slightly elevated projection in proximities of apex (from this point the carinae decrease in height). Area between carinae longitudinally sulcate. Area behind eyes smoother than on dorsal surface. Distance between upper ocular lobes equal to 1.6 times the width of one lobe. Antennal tubercles slightly apart at base; basal two thirds coarsely, confluently punctate; apical third smooth. Clypeus finely, sparsely punctate; pilosity moderately long, sparse. Labrum smooth, strongly sloping down at apical half, distinctly narrowed at apex; pilosity long, moderately abundant. Head laterally, behind eyes, with two large tubercles (apex acute), punctate on dorsal surface, granulose on lateral and ventral surface. Genal apex not strongly elongate, with small spine. Hypostomal sclerite finely, abundantly punctate; pilosity moderately long, abundant. Mandibles ( Fig. 2, 3, 5 ) slightly longer than head, coarsely, confluently punctate on basal third, punctures gradually finer and sparser towards apex (both on dorsal and ventral surface); mandibles asymmetric ( Fig. 2 ); apices of both mandibles very broad; basal tooth of apex of left mandible not projected, forming almost a right angle between inner edge of apex and large and deep concavity before it; basal tooth of apex of right mandible acute and distinctly projected; inner margin of left mandible with two small, somewhat acute teeth (sometimes, the basal is smaller than other); inner margin of right mandible with concavity before apex not large and deep and a single, small, distinct tooth before it. Scape slightly enlarged towards apex; dorsal surface coarsely, abundantly, confluently punctate (mainly towards inner side); latero-outer face distinctly finer and sparser punctate than on dorsal face; ventral face transversely rugose. Antennomere III twice as long as scape. Antennomeres III-V slightly flattened dorso-ventrally (mainly antennomere III); inner apex rounded; outer apex projected, without spine.

Pronotum rugose, except on anterior and posterior areas, which are smooth or finely and sparsely punctate; pilosity moderately long, erect, abundant, barely noticeable in dorsal view; lateral margins with three large wide teeth; posterior angle projected, obtuse. Prosternal process with broad, very distinct keel from base. Scutellum with short, abundant hairs. Elytra rugose (rugosity coarser on basal half and gradually finer towards apex); humerus with somewhat short, but very distinct spine; sutural apex with short spine (sometimes absent). Metasternum finely punctate; punctures very abundant laterally and close to the metacoxal cavities, clearly sparser on triangular area around metasternal suture. Ventrites I-III very finely, sparsely punctate; almost glabrous, except on lateral and basal area. Ventrites IV finely punctate (punctures more abundant than on I-III); pilosity sparse throughout. Ventrite V abundantly, finely punctate; pilosity abundant. Apical half of dorsal surface of profemora coarsely, moderately abundantly confluently punctate; dorsal surface of meso- and metafemora finely, sparsely punctate. Protibiae uniformly enlarged from base to apical third, and slightly narrowed from this point towards apex; ventral surface abundantly pilose. Apices of metatarsomeres I-III distinctly spinose.

Female ( Fig. 6 ). Body elongate. Head, without mandibles, about as long as wide. Distance between upper ocular lobes about length of scape. Cephalic carinae as in males, but usually more distance between them. Antennae almost reach apical third of elytra; scape just surpasses posterior edge of eyes; antennomere III almost twice length of scape. Mandible as long as head. Apex of genae short, narrow and acute. Pronotum as in males. Elytral lateral margins almost parallel on basal half, convergent towards apex at apical half; apex rounded; sutural angle without spine; sculpture as in males. Fore tibiae not very narrow, distinctly enlarged near apex. Metatarsomere I longer than II; metatarsomere V about as long as I-III together.

Variation. Male: elytral color pattern from light brown (usually darker on base) to almost black; spine of elytral sutural angle from distinct to almost absent; lateral tubercles on head from small to large; central anterior third of pronotum from sculptured to almost smooth; central anterior third of pronotum from sculptured to almost smooth. In specimens from Ecuador (2 exs.), cephalic carinae are similar to others in dorsal view but slightly more developed in lateral view. Female: head, without mandibles, longer than wide; distance between upper ocular lobes equal to about 1.7 times length of scape; antennomere III as long as 1.5 times length of scape; elytral lateral margins sometimes more rounded from base to apex, but never strongly enlarged at middle, or sub-parallel from base to apical third.

Dimensions in mm (male/female). Total length (including mandibles), 57.0-65.5/51.0-56.0; length of prothorax, 7.0-8.0/7.0-8.0; width of prothorax between the apices of the anterior angles, 16.0-15.0/14.0- 20.0; width of prothorax between the apices of the posterior angles, 12.0-13.8/11.0-14.0; humeral width, 19.0-23.0/19.0-23.0; elytral length, 32.0-42.5/32.0-35.0.

Geographical distribution. Described from Colombia (no specific locality). We add two more countries: Ecuador and Brazil (Amazonas).

Material examined. ECUADOR, Imbabura: Lita (1000 m), female, 05.II.1982 [no collector indicated] ( ZKCO) ; 2 males, XII.2002, [no collector indicated] ( ZKCO). Napo: Baeza , male, XI.2000, [no collector indicated] ( ZKCO) . COLOMBIA, female, I-II.1982, [no collector indicated] ( ZKCO). Boyaca: Muzo, male [no date or collector indicated] ( ISNB) ; female, 05.II.1976 [no collector indicated] ( ZKCO). Caquetá: male, 16.VI.1975, [no collector indicated] ( DHPC) ; male, XI.1980, [no collector indicated] ( DHPC) . BRASIL, Amazonas : male, I.1960, [no collector indicated] ( ZKCO) .

Remarks. Thomson (1877) stated that the species he named as P. modestus should receive the name of P. mygaloides , and that the species he named P. mygaloides should receive the name of P. modestus . Thomson (1877) explained that the female he originally included in P. mygaloides ( Thomson, 1859) should be excluded, because it belonged to P. sallei Thomson, 1858 . In other words, Thomson (1877) affirmed that the male included in his (1959) description of P. mygaloides actually belonged to P. modestus .

Lameere (1885b) proposed a new name for P. mygaloides sensu Thomson (1877) (translation): “The crossover of names that Mr. J. Thomson proposed between the two species seems to me likely to give rise to confusion in the future: it would be better, I think, give what he has described as the modestus , and that he would call mygaloides (Rev. Zool. 1877, p. 257) , the name Thomsoni.” Indeed, the name proposed by Lameere (1885b) is valid not because the changes proposed by Thomson (1877) are confusing (and they really are), but because P. modestus sensu Thomson (1859) is a homonym of P. modestus Fries, 1835 , and P. mygaloides Thomson, 1859 is a synonym of P. modestus Fries, 1835 .

Thus, the bibliography recorded by Quentin and Villiers (1983) for P. thomsoni is correct:

“ P. thomsoni Lameere, 1885

= P. modestus Thomson, 1859

= P. mygaloides Thomson, 1877 nec Thomson, 1859 (mâle)”.

Quentin and Villiers (1983) synonymized P. thomsoni with P. modestus , without explaining their rationale (translation): “Lameere listed for this very widespread species, the following synonyms: mygaloides Thomson, 1859 (male); wallisi Taschenberg, 1870 ; limbatus Taschenberg, 1870 (male); deyrollei Thomson, 1877 ; castaneipennis Thomson, 1877 and batesi [sic] Thomson, 1877. Of these, should be removed deyrollei male, that belongs to the group with spinous antenna, and be added thomsoni Lameere, 1885 .”

Psalidognathus thomsoni differs from P. modestus by the shape of the cephalic carinae and by the antennomeres III-V slightly flattened dorso-ventrally. In P. modestus the cephalic carinae have a large tooth on the apex, and they are strongly divergent beyond the eyes, and the antennomeres III-V are not distinctly flattened dorso-ventrally. It differs from P. onorei Quentin and Villiers, 1983 , mainly, by the protibiae uniformly enlarged from the base ( Fig. 2-4 ). In P. onorei the protibiae are enlarged only around the middle ( Fig. 8, 9 ).

Among the species that Quentin and Villiers (1983) placed in the group with antennomeres unarmed or unidentate at the apex, P. thomsoni most resembles P. erythrocerus Reiche, 1840 , P. reichei Quentin and Villiers, 1983 , and P. pubescens Quentin and Villiers, 1983 . It differs from them by: color usually uniformly dark; cephalic carinae parallel throughout in dorsal view. However, in the latter three species, the elytral color is lighter (brown-reddish), and the cephalic carinae diverge at the apical third. It also differs from P. reichei and P. pubescens by the lack of a conical and projected tooth at the apex of the cephalic carinae. It differs from P. erythrocerus by its shorter antennae, not reaching the elytral apex, and by its shorter antennomere III, twice as long as scape. In P. erythrocerus the antennae reach the elytral apex, and antennomere III is more than twice the length of the scape.

Jeniš (2010) included figures of the males and females of P. thomsoni , but did not formally revalidate the species. This makes the nomenclatural act (revalidation) questionable. The two dark males (p. 20 and 86) and the female (p. 20 and 87) really are P. thomsoni . However, the male with lighter elytra (p. 20) is probably not this species: the scape is shorter and thicker; the elytra wider and more truncate at the apex; and the tarsi longer.

Figures

Figure 1-7. Psalidognathus thomsoni. 1) Lectotype male, dorsal habitus. 2) Lectotype male, head and pronotum. 3) Lectotype male, partial lateral view. 4) Male, dorsal habitus. 5) Male, head showing cephalic carinae. 6) Female, dorsal habitus. 7) Lectotype, labels. Photos 1, 2, 3, and 7 by Eugenio Nearns.

Figure 8-13. Dorsal habitus. 8) Psalidognathus erythrocerus, neotype male. 9) P. erythrocerus, male from MNHN. 10) P. erythrocerus, female. 11) P. onorei, holotype male. 12) P.onorei, male. 13) P. onorei, female. Photos 8 and 9 from Eugenio Nearns. Photo 12 by Ivo Jeniš.