Xystonyttus ichneumoneus (Fabricius, 1803)

Gil-Santana, Helcio R. & Oliveira, Jader, 2023, A new genus and a new species of wasp-mimicking Harpactorini (Hemiptera, Heteroptera, Reduviidae, Harpactorinae), with an updated key to the Neotropical genera, ZooKeys 1152, pp. 163-204 : 163

Xystonyttus ichneumoneus (Fabricius, 1803)

Figs 101-108

Zelus ichneumoneus Fabricius, 1803: 286 [description; "Habitat in America meridionali"].

Cosmonyttus ichneumoneus Stål, 1868: 103-104 [redescription; color varieties “a”, “b” and “c”; record from Suriname]; Stål 1872: 83 [catalog]; Lethierry and Severin 1896: 178 [catalog; cited as being from Guyana].

Myocoris ichneumoneus Walker, 1873b: 129 [catalog; record from Brazil].

Xystonyttus ichneumoneus Kirkaldy, 1909: 388 [type species to Xystonyttus , new name to Cosmonyttus Stål, 1872]; Haviland 1931: 150 [record from Guyana]; Wygodzinsky 1949: 48 [catalog; cited as being from [British] Guyana]; Maldonado 1990: 324 [catalog; cited as being originally described from [British] Guyana]; Gil-Santana et al. 2003: 12 [comment on its etymology].

Notes.

The general similarity of X. ichneumoneus (Figs 101 , 102 , 104 , 105 ) with ichneumonids certainly led Fabricius (1803) to name it as such ( Gil-Santana et al. 2003). Fabricius (1803) recorded the species from South America ("America meridionali") without specifying a country or location. The citations of Guyana ("British Guiana") as the country from which the species was described, apparently were first stated by Lethierry and Severin (1896). Possibly, it was assumed because Fabricius (1803) cited "Dom. Smidt. Mus. Dom. de Sehestedt" when stating about the specimens of Zelus ichneumoneus examined by him. In fact, "most of the numerous South American species that Fabricius described and for which a certain Smidt is cited as a collector are found only in the Copenhagen Museum, in Tönder Lund’s and Sehestedt’s famous collections ( …). The only information ( …) on Smidt is that he visited besides several West Indian islands, certain places on the South American mainland, such as Essequibo and Demerara in the present British Guiana; therefore all of the South American species cited as having been collected by Smidt can with certainty be considered as coming from the vicinity of the named localities, and this is just what one who is familiar with American Hemiptera and their distribution immediately perceives" ( Stål 1868: 3, translation by G. C. Steyskal in Papavero 1971: 21). Stål (1868: 104), however, when recording the distribution of X. ichneumoneus maintained the original statement of Fabricius (1803) ("America meridionalis. Dom Smidt. (Mus. Sehestedt)"), adding: "Surinam. (Mus. Holm.)". The latter refers to the specimen(s) examined and considered as belonging to X. ichneumoneus by himself in Stockholm Museum (currently, Swedish Museum of Natural History, Stockholm, Sweden), while Stål (1872) restricted the occurrence of the species to Suriname only. In any case, Haviland (1931) recorded X. ichneumoneus from Kartabo, Bartica District, Guyana, confirming the presence of the species in this country.

In the Natural History Museum of Denmark (ZMUC), Copenhagen, Denmark, there are two type specimens of X. ichneumoneus , both of them females, and considered here as syntypes, following Art. 73.2 of ICZN. In the syntype catalogued as ZMUC 00 103079, the head, fore legs, and a portion of the prothorax are missing (Figs 101 , 102 ), while the other syntype, numbered as ZMUC 00 103080, is quite well preserved, with only the antennae and most tarsi missing (Figs 104-107 ). In the original label attached to the latter syntype (Fig. 108 ) the word " ichneumoneus " is clearly legible. Both specimens seem to belong to the same species judging by the remaining portions of the syntype ZMUC 00 103079 (Figs 101 , 102 ), while the characteristics observed in the syntype ZMUC 00 103080 (Figs 104-107 ) agree very well with the original description ( Fabricius 1803: 286). The photographs presented here are helpful to ascertain not only the characteristics of the species but also those regarded as establishing limits between the recognized genera of Neotropical wasp-mimicking Harpactorini .

The concise description of the coloration of the specimens of X. ichneumoneus , as recorded by Haviland (1931), without mention of any variation, was quite similar not only with the original description of the species ( Fabricius 1803) but also with that observed in the syntypes (Figs 101 , 102 , 104-107 ). The color variations attributed to X. ichneumoneus by Stål (1866), however, are in need to be reviewed by examining series of specimens with more comprehensive approaches, since they may be variations of this single species or may represent two or more different species.

Figures

Figures 101 - 108. Zelus ichneumoneus Fabricius, 1803, female syntypes deposited in ZMUC 101 - 103 syntype catalog number ZMUC 00 103079 101 dorsal view 102 ventral view 103 labels 104 - 108 syntype catalog number ZMUC 00 103080 104 dorsal view 105 ventral view 106 head, pronotum, fore legs, lateral view 107 head and most part of pronotum, dorsal view 108 labels. Scale bars: 5.0 mm (104, 105); 2.0 mm (101, 102, 106, 107).