Reikosiella Yoshimoto

Fusu, Lucian, 2013, A revision of the Palaearctic species of Reikosiella (Hirticauda) (Hymenoptera, Eupelmidae), Zootaxa 3636 (1), pp. 1-34 : 4-5

publication ID	https://doi.org/ 10.11646/zootaxa.3636.1.1
publication LSID	lsid:zoobank.org:pub:F5D59132-E5EC-4654-9FDE-514C654645F2
DOI	https://doi.org/10.5281/zenodo.6161144
persistent identifier	https://treatment.plazi.org/id/2940879E-FFFF-FFAE-FF6C-FF7CFD87AA95
treatment provided by	Plazi
scientific name	Reikosiella Yoshimoto
status

Treatment

Reikosiella Yoshimoto View in CoL View at ENA

Finlayia Girault, 1934: 1 . Type species: Finlayia puella Girault by monotypy. Unavailable by ICZN Article 13 (Bouček 1988: 558). Preoccupied by Finlayia Giles, 1904: 366 (Diptera) .

Reikosiella Yoshimoto, 1969: 627 –628. Type species: Reikosiella melina Yoshimoto by monotypy and original designation.

Hirticauda Bouček, 1988: 558 . Type species: Cerambycobius pax Girault by original designation. Subgeneric rank by Gibson, 1995: 259–261, 263.

Capreocauda Gibson, 1995: 262 (subgenus of Reikosiella ). Type species: Idoleupelmus tsaratananae Risbec by original designation.

Incohata Gibson, 1995: 263 –264 (subgenus of Reikosiella ). Type species: Reikosiella (Incohata) guttata Gibson by original designation.

Remarks. The main difference between Reikosiella and Eupelmus is that Reikosiella females have Mt7 (the segment with spiracles) undivided and Mt6 is not produced extensively over Mt7 (Bouček 1988) ( Figs 11 – 13, 16 View FIGURES 7 – 16 , 45, 49 View FIGURES 45 – 54 ). In Eupelmus females, Mt6 is produced posteriorly so that Mt7 is partly or mostly concealed beneath it, and Mt7 has an incised apex and is medially divided by at least a hyaline line (Gibson 1995). Another character of Reikosiella females is the shape of the scrobal depression, which is broad and shallow, and extends to the inner orbits so that the parascrobal region is virtually absent, except for the lower parascrobal region which protrudes angularly (e.g. Figs 1–6 View FIGURES 1 – 6 , 46, 50 View FIGURES 45 – 54 ) (usually in Eupelmus the parascrobal area is distinct and the lower parascrobal region is only rarely protuberant). These characters are only apparent in specimens with the head and metasoma not collapsed due to air drying (as in Figs 15 View FIGURES 7 – 16 , 41 View FIGURES 41 – 44 ). The fore wing is also usually distinctly elongate and narrow, with the marginal vein appearing distinctly longer than the costal cell (e.g. Figs 17–21, 45, 49), and always without a differentiated linea calva. The mid tibia lacks an oblique apical groove and either lacks apical pegs or these are inconspicuous, being similar in color to the apex of the tibia. The mesotarsus has a single row of pegs along each side of the tarsomeres, with the pegs of similar color as the tarsus or with slightly pigmented apices. This latter mesotarsal peg structure is found only in E. ( Episolindelia Girault ) among regional species of Eupelmus .

Reikosiella (Hirticauda) Bou ě ek

Finlayia Girault, 1934 .

Hirticauda Bouček, 1988 .

Reikosiella (Hirticauda) : Gibson, 1995: 259–261, 263.

Remarks. All Palaearctic species of Reikosiella belong to the subgenus Hirticauda , which was erected originally as a genus for a group of species mostly similar to species classified in Reikosiella except for the shape of the head and conformation of the ovipositor sheaths (Bouček 1988). Gibson (1995) considered that the differences were only conspicuous modifications of an Old World group of species related to New World species of Reikosiella and treated Hirticauda as one of four subgenera in the genus. Females of R. ( Hirticauda ) differ from females of the other subgenera by the structure of their acropleural sulcus, which curves, sinuately, to the anterolateral angle of the mesocoxa so as to delineate a slender mesepisternum above the mesocoxa and, in most species, by the presence of a straight row of pale mesotibial apical pegs (Gibson 1995). These pegs are present in all Palaearctic species, though sometimes they are difficult to see because they are concolorous with the apex of the mesotibia. Females of world species of R. ( Hirticauda ) often also have a bicolored antenna, with one to several funicular segments white ( Figs 52, 54 View FIGURES 45 – 54 ) (Gibson 1995). However, six of the ten Palaearctic species, including the most common R. rostrata comb. nov., are atypical because females have a completely dark flagellum ( Fig. 48 View FIGURES 45 – 54 ) similar to Eupelmus . Most females also have F1 anelliform to slightly longer than wide (Gibson 1995), but up to twice as long as wide in R. cornuta sp. nov. ( Fig. 24 View FIGURES 23 – 30 ).

The posterior margin of the syntergum is omega-like emarginate in nearly all females of Reikosiella , including those of R. ( Hirticauda ). Usually, there is a distinct surface anterior to the terminal emargination (Gibson 1995), though occasionally in Palaearctic species of R. ( Hirticauda ) Mt7 covers Mt8 (syntergum) up to the dorsally facing anal sclerite (in R. vanharteni sp. nov., Fig. 26 View FIGURES 23 – 30 ). Also, in one species ( R. koreana sp. nov.) the anal sclerite is displaced anteriorly so that the syntergum extends posterior of the emargination to surround the anal sclerite as a gradually slopping, medially divided surface ( Fig. 29 View FIGURES 23 – 30 ). In all Palaearctic species the female metasoma is ovoidal, being wider in the distal half, and is whitish ventrobasally and sometimes with a subbasal dorsal whitish band ( Figs 10–13 View FIGURES 7 – 16 , 45, 49 View FIGURES 45 – 54 ). Regional females of Eupelmus have this metasomal structure and color pattern only in the subgenus Macroneura Walker , which contains species with brachypterous females and hence impossible to confuse with Reikosiella females, which are always macropterous.

Females of all Palaearctic species of R. ( Hirticauda ) have infuscated fore wings, with the infuscation pattern usually consisting of a band behind the parastigma, a second broader band or spot behind the distal part of the marginal and postmarginal veins, and a diffuse spot at the apex. Species having reduced infuscation have the second spot inconspicuous or absent and the wing apex clear ( Fig. 28 View FIGURES 23 – 30 ), whereas those species with strongly infuscated fore wings have a pattern similar to that of many Anastatus Motschulsky females, consisting of a median transverse cross-band on an infuscated disc ( Figs 24–25 View FIGURES 23 – 30 ). Females of many species also have a stigmal vein with a thick and conspicuously elongate uncus or a posteriorly angularly expanded stigma, or both ( Figs 34, 35, 37–39 View FIGURES 31 – 40 , 47, 53 View FIGURES 45 – 54 ). Females of a few rare regional Eupelmus have similar infuscation patterns, but the stigmal vein lacks such modifications.

Some regional Reikosiella males are similar to Merostenus males, having a similar head, antenna, fore wing, and a gracile body, but can be separated based on differences in structure of the metapleuron and mesepimeron using the key given by Gibson (1995). Merostenus males are also easily recognized and separated from all known Palaearctic Reikosiella males by color of the metasoma and fore wings. In Merostenus , Mt2 is contrastingly darkyellow to pale brownish and the fore wing is slightly and uniformly infuscated ( Fig. 44 View FIGURES 41 – 44 ), whereas Reikosiella males have the metasoma uniformly colored and the fore wing clear. Gibson (1995) was not very sure of the constancy of the presence of a shallow depression at the apex of the interantennal area in Merostenus males, but examination of about twenty uncollapsed, chemically dried specimens from Romania and Greece (AICF) showed the presence of at least a hint of this depression in all specimens (usually it is well visible) ( Fig. 43 View FIGURES 41 – 44 ); a short subocellar sulcus is also present in all specimens. Reikosiella males can be separated from Eupelmus males, especially those of E. ( Macroneura ) with a similarly gracile body and gracile-filiform flagellum, using features of the antenna, head, fore wing setation, and shape of the gaster. Regional males of Eupelmus have a row of long erect setae on the pedicel ventrally (except for most E. ( Episolindelia ) species), segments of the antennal funicle abut, the lower gena has one longer seta and sometimes additional long, curved setae on the lower face above the malar sulcus (with a few exceptions), the fore wing has a speculum, and the metasoma has a wide base. Males of Palaearctic Reikosiella have varied antennal structures but the pedicel ventrally lacks a row of long erect setae. Usually also the flagellum is gracile-filiform with the funicle segments separated by short petioles (e.g. Fig. 22) and covered with long, semierect setae (except males of R. koreana sp. nov.). Further, the lower gena has subequally short setae. Males also have an elongate fore wing that is entirely, sparsely setose without a speculum and the gaster appears petiolate in dorsal view in three out of the five species for which males are known because the basal segment is compressed (e.g. Fig. 42 View FIGURES 41 – 44 ). Reikosiella males from other regions usually have a small pit or shallow depression in the scrobal depression at the apex of the interantennal region (Gibson 1995), but this is absent from all but one Palaearctic species for which males are known.