Criodion tomentosum Audinet-Serville, 1834

Santos-Silva, Antonio & Devesa, Sergio, 2021, New synonymies and notes in Criodion Audinet-Serville (Coleoptera: Cerambycidae: Cerambycinae), Insecta Mundi 2021 (897), pp. 1-7 : 2-6

Criodion tomentosum Audinet-Serville, 1834

( Fig. 1–5 , 7–26 )

Criodion tomentosum Audinet-Serville 1834: 572 .

Criodion angustatum Buquet 1852: 358 . New synonym

Criodion pilosum Lucas 1859: 188 . New synonym

Criodion hirsutum Bates 1870: 206 .

Audinet-Serville (1834) described Criodion tomentosum (see photograph of the holotype on Bezark 2021) as follows (translated): “(Length almost two inches.) Body of a shiny blackish brown, all covered with lying, yellowish pubescence, those of the elytra longer than the others. Antennae and legs with same color of the body and with dense yellowish pubescence. Mesofemora having their posterior external angle extended into a distinct spine. Male. From Brazil.” Additionally, he included the species in his first division of the genus, which has the elytral apex rounded, with only the sutural angle with a small spine.

Buquet (1852) described Criodion angustatum ( Fig. 4 ) as follows (translated): “Narrow, dark, setose. Elytra parallel-sided, apex rounded. Abdomen reddish. Length, 32 mm; width, 8 mm. Body very elongated, dark brown, entirely covered with dense gray setae. Head fairly strong, with a small longitudinal carina not very prominent at the top, behind the antennae. These [antennae] also covered with gray setae, are a little shorter than the body, and punctate on base. Prothorax longer than wide, uneven and wrinkled dorsally. Scutellum large, acute apically. Elytra very long, slightly wider basally than the prothorax, rounded apically, with a short spine at sutural angle. Ventral surface of the body and legs dark brown; abdominal segments reddish. This insect is from Brazil; it was given to me by Mr. H. Jekel.”

Later, Lucas (1859) described Criodion pilosum ( Fig. 1–3 ) as follows (translated): “Length, 38 mm; width 10 mm (male). Length, 56 mm; width 11 to 13 mm (female). It is smaller and especially narrower than C. tomentosum, Dej. ; reddish brown, and entirely covered with grayish-yellow pubescence. The head is quite elongated and strongly punctate. The antennae in male are slender and slightly longer than the body. The thorax, a little wider than long, is covered with roughness which forms transverse folds on sides. The scutellum is triangular and completely smooth. The elytra, wider than the thorax, with protruding shoulders, are elongate and slightly narrowed in their middle part; they are covered by fine and slightly dense; at apex, they are rounded, with the sutural spine stronger and more elongated than in C. tomentosum . The entire ventral surface and the legs are dark brown. The female differs from the male not only by the antennae, which are much shorter, but also by its size, which is larger and above all rougher. Brazil interior.”

Finally, Bates (1870) described Criodion hirsutum ( Fig. 5 ) as follows (translated): “Elongate, narrow, brown, with yellowish-grey pubescence, decumbent on thorax and elytra. Head rugose, with elongate tubercle between the eyes. Thorax square, sides slightly rounded and wrinkled-tuberculate, dorsally almost smooth with coarse punctures and three distinct smooth tubercles. Elytra abundantly punctate, rounded at the apex, with only the suture spined, clothed with sparse decumbent pubescence. Meso- and metafemora with apex unispinose, tibia distinct spined at the apex externally. Mesocoxal cavities slightly open laterally. Length 36.05 mm; elytral width 9.55 mm. From Brazil. Collected by Read.”

According to Martins and Monné (2005) on Criodion tomentosum Audinet-Serville, 1834 (translated): “Specimens identified by Melzer as Criodion tomentosum do not agree with the slide of the holotype taken by J. S. Moure at BMNH (former collection Chevrolat), which shows the elytral apex with distinct sutural spine. This feature, moreover, corresponds to the divisions of the genus Criodion proposed by Audinet-Serville (1833: 572). The first division united species with «Elytres arrondies au bout et munies d’une petite épine a leur angle sutural». This division included Criodion tomentosum and Criodion corvinum Germar, 1824 , now placed in Coleoxestia […] The material from former Melzer collection and the specimens identified by J. F. Zikán (also in the former collection Melzer) is now at the MZSP. In the species identified by Melzer as C. tomentosum , the elytra are completely unarmed and the elytral pubescence has no setae interspersed. In the specimens that agree with the holotype of C. tomentosum , the elytra have sutural spine and the elytral pubescence has white setae interspersed, longer and distinct especially close to suture on posterior half. The specimens identified by Melzer and Zikán correspond to C. angustatum , which slide of the holotype was examined. The identification did by us seems correct and, in this case, C. hirsutum Bates, 1870 is a synonym. C. hirsutum was based on a specimen from Bahia, with the elytral pubescence quite damaged, from which we examined the slide of the holotype taken by J. S. Moure at MHNH. The holotype is a female and also has the sutural spine on the elytra, but the longer setae of the elytra are not visible because the surface is damaged […] Melzer identified specimens of C. tomentosum as Criodion pilosum Lucas , which holotype we did not examine and, therefore, we cannot decide about the status only based in the original description and figures.”

In their key to species of Criodion, Martins and Monné (2005) separated C. tomentosum , C. angustatum , and C. pilosum as follows (translated):

7(6). Elytra with long setae between pubescence. Brazil (Goiás, Pernambuco to Rio Grande do Sul)........

.............................................. C. tomentosum Audinet-Serville, 1833 [sic] — Elytra with uniform pubescence, practically without setae interspersed.......................... 8

8(7). Lower eye lobes with setae between ommatidia, especially on posterior area ( C. pilosum was not exam-

ined)............................................................................... 9 — Lower eye lobes without or with rare setae between ommatidia................................ 10

9(8). Antennae in female reaching the apical quarter of the elytra; elytral apex unarmed or with minute sutural

spine. Brazil (Minas Gerais to Santa Catarina), Paraguay, Argentina (Misiones).................

........................................................... C. angustatum Buquet, 1852 — Antennae in female slightly surpassing the middle of the elytra; elytral apex with distinct sutural spine.

“ Brasil interior”.................................................. C. pilosum Lucas, 1857

The first thing that is possible to see is that the geographic distribution of the three species is overlapped. Examining several specimens identified as C. tomentosum ( Fig. 23–24 ) and C. angustatum ( Fig. 25–26 ) in the MZSP collection, it is possible to see that all of these features used in the key are highly variable: the quantity of erect setae on the elytra is variable in the specimens identified as C. tomentosum , from somewhat abundant to almost absent; although the sutural angle of the elytra is always projected, the projection is very variable, from minute to forming a distinct spine (never long); the body shape is also very variable, from somewhat slender to distinctly wider, including the proportions between prothorax and elytra. On the other hand, a considerable number of specimens identified as C. angustatum also have these features very variable, not rare, with distinct erect setae on posterior area of the elytra, and with distinct projection on the sutural angle. Furthermore, all specimens of C. tomentosum and C. angustatum have distinct setae between the ommatidia ( Fig. 19–22 ), and the width of the lower eye lobes is variable; the body shape is variable, from distinctly narrow to stout; the size of the specimens is very variable, with specimens somewhat small to distinctly large; the length of the antennae is variable in both sexes, especially in females ( Fig. 1 , 7, 11, 13 ), from slightly surpassing middle of the elytra to reaching about posterior quarter; the apex of the meso- and metafemora is variable, with a projection only on inner side or on both sides (projection from small to distinctly spiniform); and the shape of the prothorax is variable, from somewhat narrow to wide. Corroborating the observation of these variations, unrelated to geographic distribution, it is possible to see that the holotype female of C. hirsutum , synonymized with C. tomentosum by Martins and Monné (2005) has the antennae reaching about the posterior quarter of the elytra (a feature pointed out by them as present in C. angustatum ), and the elytral sutural angle with a distinct projection (a feature pointed out by them as present in C. tomentosum ). Therefore, even this feature cannot be used to separate the species. Also, although the holotype of C. pilosum has the eyes dirty, it is possible to see that the setae between the ommatidia are also present. Finally, the antennal length is too variable in specimens of C. tomentosum and C. angustatum , and therefore, cannot be used to separate them.

Based on the high variability of features currently used to separate these three species, examination of several specimens identified as C. angustatum and C. tomentosum , comparison of photographs of the holotypes, original descriptions and redescriptions, our conclusion is that C. pilosum and C. angustatum are junior synonyms of C. tomentosum .

The list of specimens present in the MZSP collection ( C. tomentosum and C. angustatum ) can be seen in Martins and Monné (2005). After this publication, a few specimens were incorporated to the collection. Two specimens are present in SDPC collection, both from Brazil: Rio de Janeiro, Nova Friburgo, 1 female (44.2 mm), XII.2016, local collector ( Fig. 7–8 ); and Santa Catarina, Corupá, 1 male (40.1 mm), V.1975, local collector ( Fig. 9–10 ).

The syntype female of Criodion pilosum has a label ( Fig. 3 ) indicating that the specimen is a lectotype. However, a lectotype of the species was never designated.

Figures

Figures 1–6. Criodion spp. 1–3) Criodion pilosum Lucas, 1859, syntype female: 1) Dorsal habitus. 2) Ventral habitus. 3) Labels. 4) Criodion angustatum Buquet, 1852, holotype female, dorsal habitus. 5) Criodion hirsutum Bates, 1870, holotype female, dorsal habitus.6) Criodion tuberculatum Gahan, 1892, syntype male, dorsal habitus.

Figures 7–22. Criodion tomentosum Audinet-Serville, 1834: 7–8) Female (SDPC), from Brazil (Nova Friburgo, Rio de Janeiro):7) Dorsal habitus. 8) Ventral habitus. 9–10) Male (SDPC), from Brazil (Corupá, Santa Catarina): 9) Dorsal habitus. 10) Ventral habitus. 11–12) Female (MZSP), from Brazil (Rio de Janeiro city, Rio de Janeiro): 11) Dorsal habitus. 12) Lateral habitus. 13–14) Female (MZSP), from Brazil (Laranjal, São Paulo): 13) Dorsal habitus.14) Lateral habitus. 15–16) Male (MZSP), from Brazil (no further data): 15) Dorsal habitus. 16) Lateral habitus. 17–18) Male (MZSP), from Brazil (Caxias, Maranhão): 17) Dorsal habitus. 18) Lateral habitus. 19–22) Lower eye lobes: 19) Male. 20) Female. 21) Female. 22) Male.

Figures 23–26. Criodion tomentosum Audinet-Serville, 1834, from MZSP collection: 23) Specimens identified as C. tomentosum. 24) Specimens identified as C. tomentosum. 25) Specimens identified as C. angustatum. 26) Specimens identified as C. angustatum.