Idiomacromerus asphodeli Ribes, 2019

Delvare, G., Escolà, A. Ribes, Stojanova, A. M., Benoit, L., Lecomte, J. & Askew, R. R., 2019, Exploring insect biodiversity: the parasitic Hymenoptera, chiefly Chalcidoidea, associated with seeds of asphodels (Xanthorrhoeaceae), with the description of nine new species belonging to Eurytomidae and Torymidae, Zootaxa 4597 (1), pp. 1-90: 66-68

publication ID

https://doi.org/10.11646/zootaxa.4597.1.1

publication LSID

lsid:zoobank.org:pub:F8FD30CA-1B84-4134-91BC-B69736DB0EA8

persistent identifier

http://treatment.plazi.org/id/03ED8793-FFB8-3B41-D9F0-A053E39BF8F4

treatment provided by

Plazi

scientific name

Idiomacromerus asphodeli Ribes
status

sp. n.

Idiomacromerus asphodeli Ribes   sp. n.

( Figs 29 View FIGURES 29 A–F)

Type material. Holotype ♀: SPAIN: Castellón, Vinarós , 40.49368°N 0.20821°E, ex fruit of A. fistulosus   , collected 7.vi.2012, emerged 22.vi.2012 (A. Ribes) (in MNCN) GoogleMaps   . Allotype ♂: same data as holotype (in MNCN) GoogleMaps   . Paratypes (40 ♀ 40 ♂): same data as holotype except emergence dates 21–22.vi.2012 (6 ♀ in BMNH, 7 ♀ in NMS, 2 ♀ 2 ♂ to GDPC for photography, the rest in MNCN and RAPC) GoogleMaps   .

Other material. SPAIN: Castellón, Vinarós , 40.49368°N 0.20821°E, ex fruits of A. fistulosus   , collected on 7.vi.2012, adults emerged on 8.vi–15.vii.2012 (269 ♀ 284 ♂, some probably in BMNH) GoogleMaps   ; Lleida, Alfes, 41.54843°N 0.65482°E, ex fruits of A. fistulosus   , collected on 21.vi.2011, adult emerged on 25.vi.2011 (A. Ribes) (1 ♂) GoogleMaps   ; La Granja d'Escarp, 90 m, 41.40481°N 0.33695°E, ex fruits of A. fistulosus   , collected on 20.iii.2012, adults emerged in 2012 (A. Ribes) (5 ♀ 6 ♂) GoogleMaps   ; Tarragona, García , 75 m, 41.13127°N 0.65186°E, ex fruits of A. fistulosus   , collected on 7.vi.2012, adults emerged on 18–28.vi.2012 (A. Ribes) (1 ♀ 3 ♂) GoogleMaps   .

Etymology. Named after the host plant.

Condition of holotype.Complete specimen glued by right ventrolateral mesosoma and gaster to card point pinned over card rectangle.

Description of females from the type series ( Fig. 29A View FIGURES 29 ). Length excluding ovipositor 1.7–2.1 mm, ovipositor sheaths length 0.6–0.7 mm. Head, mesosoma and gaster coppery, tegulae yellow; antennal scape brown, weakly metallic, with extreme base yellow, flagellum dark brown; wings hyaline, venation yellowish brown; legs with coxae coloured as body, femora metallic with yellow apices, tibiae testaceous yellow sometimes with brownish darkening medially, tarsi with 3 or 4 basal segments whitish, segment 5 and pretarsus darkened.

Head 1.20–1.26× as broad as mesoscutum, in dorsal view 1.8–1.9× as broad as long ( Fig. 29B View FIGURES 29 ); temples 0.35–0.37× as long as eye; POL 2.4–2.55× as long as OOL, OOL 1.5–1.7× as long as posterior ocellus diameter; occipital carina present but fine. Eyes 1.5–1.6× as long as broad, separated by their length, with very short and sparse pilosity. Head in front view oval, 1.1–1.2× as broad as high ( Fig. 29C View FIGURES 29 ); genae rounded, converging; malar space 0.38–0.42× length of eye, malar sulcus straight; mouth opening 2.20–2.27× as wide as malar space; lower face shiny with weak, irregular reticulate sculpture and conspicuous piliferous punctures, setae conspicuous, whitish and slightly flattened; scrobal depressions finely reticulate.

Antenna ( Fig. 29D View FIGURES 29 ) 11263; scape not reaching anterior ocellus, 0.66× as long as eye and about 4.5–5.0× as long as broad; pedicel plus flagellum about 0.95× breadth of head, pedicel less than twice as long as deep; anelli transverse, A1 about 2× and A2 about 3× as broad as long; funicle segments slightly transverse, F1 about 1.1× as stout as pedicel and subquadrate (in small specimens almost anelliform, 1.3–1.6× as broad as long), and F6 1.3× as stout as F1, F2–F6 progressively broader with F6 1.2–1.5× as broad as long; clava slightly broader than F6, about 2.4× as long as broad and half length F1–F6; flagellar sensilla in a single row on each segment, setae dense and adpressed.

Mesosoma in dorsal view 1.6–1.7× as long as broad ( Fig. 29E View FIGURES 29 ), in lateral view 1.5–1.6× as long as deep with propodeum sloping at about 45° to plane of mesoscutum-mesoscutellum ( Fig. 29A View FIGURES 29 ); pronotum 0.25–0.3× length of mesoscutum with a distinct collar rounded into the strongly sloping anterior part; mesoscutum 1.35–1.45× as broad as long, dull with fine and dense reticulation which anteriorly is arranged in more or less semicircular transverse arcs, notauli shallow posteriorly reaching margin slightly laterad of axillar grooves, setae short, decumbent and inconspicuous; mesoscutellum almost 1.1× as long as broad, frenal area not defined, reticulately sculptured with posterior half having areoles slightly broader than those on mesoscutum and with more distinct, suberect pale setae; postscutellum reticulate; propodeum medially 2.0–2.3× as long as postscutellum, almost 0.3× as long as mesoscutellum, very weakly reticulately sculptured with a fine median carina indicated in anterior third, callus with long pale setae, spiracles small and separated from metanotum by half a diameter. Metapleuron with short hairs on lower half; mesepimeron glabrous. Metacoxa with short, adpressed setation dorsally, 2 or rather more times as long as deep; pro- and metafemora somewhat broadened (respectively 3.1–3.6 and 3.0–3.3× as long as broad), metafemur with a shallow, ventral, subapical notch; metatibia with longer inner apical spur about 0.4× as long as basitarsus and shorter than apical width of tibia, the outer spur short, less than half as long as the inner spur.

Fore wing ( Fig. 29A View FIGURES 29 ) 2.2–2.35× as long as broad; costal cell about 12× as long as broad, its lower surface with two complete rows of setae and with basal and apical thirds more extensively setose, upper surface with a row of 6–8 setae at apex; basal fold setose, basal cell closed below and with several setae on upper surface behind submarginal vein; speculum closed below; ratio costal cell: marginal vein: stigmal vein: postmarginal vein as 200:84:31:41, stigma with long uncus.

Metasoma. Gaster ovate, excluding ovipositor sheaths about 1.8× as long as broad, 1.2× as broad as mesosoma, 1.3–1.4× as long as mesosoma, almost or quite as long as head plus mesosoma; hypopygium reaching almost or quite three-quarters of gaster length; GT1 occupies about 0.27× length of body of gaster with posterior margin medially incised, GT2 and GT3 with posterior margins slightly emarginate; ovipositor sheaths 0.55–0.67× length of body of gaster and 1.25–1.35× length of metatibia.

Male. Length 1.65–2.0 mm. Antennal scape with basal two-fifths of ventral surface yellow, mesothoracic dorsum more green than in female with copper colour limited to central parts, legs with yellow colouration brighter and more extensive than in female. Antenna ( Fig. 29F View FIGURES 29 ) with scape 3.4–4.1× as long as broad, 0.6× length of eye; funicle segments relatively shorter than in female, F1 1.55–1.67× as broad as long, rather narrower than pedicel; F3 1.3× as broad as long. Pro- and metafemora broader than in female, 2.36× and 2.63× as long as broad respectively. Gaster almost twice as long as broad, 1.15× as long as mesosoma and 0.87× as long as head plus mesosoma.

Recognition. Idiomacromerus asphodeli   belongs to the group of species of Idiomacromerus   which were previously segregated in Liodontomerus Gahan   and are characterized by the antennal clava lacking a hyaline apical process, the metatibia with two apical spurs, a relatively short marginal vein (less than half as long as costal cell), pronotum with a distinct collar and thorax dorsally with dense reticulate sculpture. Within this group I. asphodeli   is distinguished by having 2 (not 3) anelli, an entirely metallic mesothorax with strong coppery tints (at least on the dorsum), clear wings and an ovipositor which is shorter than the gaster but more than half as long. I. asphodeli   shares these characters with I. papaveris (Förster, 1856)   and I. centaureae (Askew & Nieves-Aldrey, 1988)   , which are parasitoids in galls of Cynipidae   , but the mesosoma of I. asphodeli   is more slender than in the two cynipid parasitoids (at least 1.6 times compared with not more than 1.5 times as long as broad), the tegulae are yellow and not darkened, and the lower face of I. asphodeli   has very distinct piliferous punctures. In addition, the occipital carina is present, although weak, in I. asphodeli   but usually absent in other Idiomacromerus   species except I. papaveris   in which it is exceedingly weak. Other known Idiomacromerus   parasitoids of Bruchophagus   are I. perplexus (Gahan, 1914)   and I. pannonicus (Ruschka, 1923)   in leguminous seeds, but these lack an occipital carina, and in addition I. pannonicus   has three anelli and I. perplexus   has a dark tegula and yellowish scape.

Distribution ( Fig. 38 View FIGURE 38 ). Idimacromerus asphodeli   was reared only from samples of A. fistulosus   seeds collected in northern Spain and it is notable that it was not collected in southern France (Languedoc-Roussillon) where A. fistulosus   and its two associated species of Bruchophagus   were found. Furthermore, it was found in only four of the sixteen Spanish samples of A. fistulosus   seeds, most specimens of I. asphodeli   emerging from samples from coastal areas of Spain, and it was present only in low numbers in samples from inland sites in Lleida.

Biology. Trophic relationships ( Fig. 43 View FIGURE 43 ). Idiomacromerus asphodeli   was reared in very large numbers from seeds of A. fistulosus   infested by B. gijswijti   and possibly by B. lecomtei   . This host-parasitoid relationship was confirmed by rearing isolated seeds and subsequent seed dissection. It is possible, however, that I. asphodeli   utilises additional hosts living in fruits and stems of A. fistulosus   .

Phenology. Idiomacromerus asphodeli   is bivoltine, the first generation attacking hosts in spring in fresh fruits and emerging as a second generation of adults between early June and mid-July from seeds formed earlier the same year. It is likely that these second generation females oviposit in seeds containing Bruchophagus   in the remaining fruits which are dry and still attached to the asphodel flower spikes, and their progeny overwinter as fully grown larvae to emerge in the following spring and oviposit in the first fresh fruits attacked by Bruchophagus   .

Sex ratio. The sex ratio is approximately even; in a total of 651 reared specimens, 48.5 percent were females and 51.5 percent males.

MNCN

Museo Nacional de Ciencias Naturales

NMS

National Museum of Scotland - Natural Sciences