Redescription of Chrysidea pumiloides Zimmermann, 1956, and description of three new species of Chrysidea from Madagascar (Hymenoptera: Chrysididae)

. Chrysidea pumiloides Zimmermann, 1956 and its Malagasy allies are taxonomically revised. As a result, C. pumiloides and C. phoebe Zimmermann, 1956 are redescribed; two new species, C. vazimba sp. nov. and C. merina sp. nov., are described from museum collections, and another new species, C. rioae sp. nov., is described based on a male recently collected in Southern Madagascar, at Berenty Reserve. The habitus of the holotypes and the male genitalia are illustrated and the key to Malagasy Chrysidea Bischoff, 1913 is updated.


Introduction
Chrysidea Bischoff, 1913 (Hymenoptera, Chrysididae) is a small genus comprising 22 species (Kimsey & Bohart 1991;Rosa & Xu 2015).It is known from Africa to Eurasia, yet 13 species are endemic to Madagascar (Azevedo et al. 2010).Malagasy species were taxonomically revised by Zimmermann (1956Zimmermann ( , 1961) ) and Bohart (1988), who described two new species and provided an identification key.They are considered as parasitoid of Sphecidae and Crabronidae sensu Sann et al. (2018) (Zimmermann 1961;Kimsey & Bohart 1991), but their biology is poorly known.Recently, Pauli et al. (2019) indicated the polyphyly of Chrysis Linnaeus, 1761 based on molecular data.They discussed that a genus-level reclassification is needed among Chrysis and related genera, including Chrysidea.Although it is difficult to define the genus Chrysis because of its great variation, Chrysidea is well recognized from Chrysis by the modified head, in front view with a bulging brow and a short and deep scapal basin, thus making the head somewhat transversely oval in lateral view; the gena with two carinae; discoidal cell of forewing with outer veins nearly nebulous in most species.Chrysidea is also recognized from Trichrysis Lichtenstein, 1876, sister to Chrysidea, by TFC topping scapal basin; discoidal cell of forewing with outer veins usually nebulous; S2 black spots distinctly separated with each other, etc. (Rosa et al. 2016).
Chrysidea pumiloides Zimmermann, 1956 was described based on the holotype and a paratype from Bekily, Madagascar (Zimmermann 1956).It is peculiar among Malagasy species because it lacks a transverse frontal carina (TFC) on frons.In the course of our study of Chrysididae in museum collections, clearly different species with distinct TFC were found among specimens previously identified as C. pumiloides.A female deposited in the Zimmermann collection at the Naturhistorisches Museum (Vienna, Austria) has a red label "TYPE" handwritten by Zimmermann himself; it was considered to be the holotype or, at least, a specimen of the type series.However, this female has a distinct TFC and its collection site is incongruent with the original description.Therefore, this female specimen should be non-type material even it bears the type label, as well as other specimens of Zimmermann observed in his collection (Rosa et al. in preparation).Actually, the true holotype is deposited at the Muséum national d'Histoire naturelle (Paris, France) as mentioned in the original description (Zimmermann 1956).It is easy to suppose that the presence of an erroneous type and its wrong identification lead to confusion for subsequent researchers.In fact, some identifications made by Linsenmaier and Bohart included different species related to C. pumiloides.The key of Bohart (1988) to Malagasy species did not mention the missing TFC of C. pumiloides, a unique feature in this species, shared only with C. asensioi Mingo, 1985 in the West Palaearctic; it was not even mentioned in the generic diagnosis of Kimsey & Bohart (1991).A taxonomic revision of historical collections and recently discovered specimens resulted in the discovery of three new species described and illustrated here.

Material and methods
Terminology follows that of Kimsey & Bohart (1991) and Rosa & Xu (2015).Male terminalia were dissected, placed in KOH (10%) and boiled for ten minutes.They were observed under a Hitachi S 3000N scanning electron microscope (Hitachi, Tokyo, Japan).Label data for historical specimens are transcribed as written on the paper card.Labels are separated from each other by quotation marks and a single slash was used for line feed.The key to Malagasy Chrysidea was made based on our observations and those of Bohart (1988).

Diagnosis
Chrysidea pumiloides is characterized by the combination of the following characters: TFC absent; head wide, 1.3-1.4× as wide as high; distal margin of T3 with large, triangular lateral teeth and area between rounded; MS = 0.6-0.8MOD; tegula brown with more or less strong blue to purple reflection; mesoscutellum with impunctate area; metanotum rounded, without anteromedian pit; T2 with microreticulate interspaces among punctures; male genitalia with distal apex of paramere flat.
Coloration.Head metallic blue-green to blue, sometimes purplish, face more greenish.Antenna dark brown with scape, pedicel, F1 and F2 metallic blue-green or blue: F1 and F2 of holotype almost dark brown.Mandible testaceous, basal ⅓ metallic blue-green, apex reddish dark brown.Mesosoma metallic blue-green, sometimes surface between notauli darkened: surface of holotype blackish with purplish luster.Tegula brown with strong purple reflection; reflection weaker, more brownish in smaller specimens and more bluish in female from Antsingy.Legs brown, with strong purplish reflection and green luster on coxae and femora: hindcoxa of a female from Behara (NHMW) metallic green; tibiae brown with greenish reflection, sometimes bluish; tarsi brown.T1 metallic blue-green, sometimes purplish, more greenish laterally and posteriorly; T2 metallic blue with purplish luster, greenish or bluish without purplish luster laterally and posteriorly; T3 metallic purple, bulged pre-pit row area usually bluish.Sterna metallic blue-green to green.

Distribution
North and south Madagascar.

Biology
Unknown.

Remarks
According to Zimmermann (1956), a paratype female should be deposited at the Musée royal du Congo belge, Tervuren, Belgium (Royal Museum for Central Africa), however, no material of C. pumiloides was found (S.Hanot, Royal Museum for Central Africa, pers.com.).On the other hand, there is a female of C. pumiloides with a type label in NHMW, but it should not be the true paratype because the specimen is incongruent with the original description and the collection locality is Annarivo (= Antananarivo?) instead of Bekily, as given in the original description.In NHMW, we found similar erroneous type labels pinned with other chrysidids, including another Chrysidea: a specimen labelled as "type" of C. phoebe Zimmermann, 1956, which is conversely described on a single holotype specimen deposited in MNHN, without paratype designation.

Distribution
Madagascar.

Biology
Unknown.

Remarks
The type locality name "Annanarivo" is ambiguous.It might indicate an area near Antananarivo, northeast of the capital city, or even a larger undefined area.The body color of Chrysidea vazimba sp.nov. is similar to that of C. pumiloides, but is easily distinguished by the presence of one TFC (Figs 3B, 4B) and humped metanotum.Morphological characters are rather similar to C. rhodopis Zimmermann, 1961;however, in C. vazimba sp. nov., interspaces among punctures on T2 are smooth and black spots on S2 are more rounded and more closely located each other (Figs 3E, 4E).

Diagnosis
Chrysidea merina sp.nov. is characterized by the combination of the following characters: double TFC present; head wide, 1.4 × as wide as high; distal margin of T3 with large, triangular lateral teeth and short median tooth, and interval faintly substraight; MS = 0.8 MOD; tegula metallic blue-green, basally purplish; T2 without microsculpture.

Etymology
Chrysidea merina sp.nov. is named after the Merina people, the largest ethnic group in Madagascar.MetasoMa.Median line scarcely visible on T1 and T2 (Fig. 5D).Punctures on T1 0.3-0.4MOD, 0.2-0.5 PD apart, with smooth interspaces; punctures on T2 and T3 smaller, 0.2 MOD, with interspaces smooth only faintly microreticulate anteriorly and posteriorly; pre-pit row area of T3 not bulged; pit row distinct, with large and deep pits.Apex of T3 with a pair of lateral triangular teeth, interval between teeth substraight, short median tooth present (Fig. 5D, F).S2 black spots (Fig. 5E) oval and medially separated by 1.3 MOD.

Male
Unknown.

Distribution
Madagascar.

Biology
Unknown.
Coloration.Head and mesosoma metallic green or blue-green with blue or purplish luster, ocellar region more bluish.Antenna black with scape, pedicel metallic green.Mandible medially testaceous, distally dark brown, basal ½ metallic green.Tegula metallic green; deep anteromedian pit on metanotum metallic blue.Legs metallic green or blue-green except tarsi entirely yellowish (Fig. 6A).Metasomal terga metallic green or blue-green with blue luster; metasomal sterna metallic green with golden luster (holotype lacks sterna).

Distribution
Southern Madagascar.

Biology
Unknown.

Remarks
Chrysidea phoebe is similar to C. phragmiticola Zimmerman, 1961.The T3 distal apex in C. phoebe is distinctly angulated and the interval between the median angle and a lateral tooth is substraight (Figs 6F, 7F); on the other hand, the posterior margin is rounded and the median angle is absent in C. phragmiticola.The body color of both species is basically metallic green, but metabasitarsus of C. phoebe is yellowish (Figs 6A, 7A), non-metallic green as in C. phragmiticola.A female in NHMW is considered to be non-type material, even if it has a type label, because no type was designated other than the holotype deposited in MNHN (Zimmermann, 1956).

Etymology
The specimen was collected during the field trip in Madagascar from January to February 2018.After that, the holotype was displayed at the summer exhibition of the National Museum of Nature and Science, Tokyo, Japan from July to October 2018.The species is named after Ms Rio Matsushima, a girl who visited the exhibition and heartily encouraged our study on this tiny blue wasp.head.Width 1.8 × as wide as high.Scapal basin deep, transversely wrinkled and punctate with sparsely located minute punctures.TFC absent (Fig. 8B).Antennomeres P, F1, F2, F3: 1.2 : 1.3 : 1.2 : 0.8; F1 l/w = 1.6;OOL = 1.7 MOD; POL = 2.0 MOD; MS = 1.2 MOD; apical margin of clypeus almost straight, faintly concave; mandible edentate, basally with a deep notch; basal width of mandible = 1.0 MOD.Brow with large, irregular and contiguous foveate punctures; PD on brow: 0.3-0.6MOD (Fig. 8B).

Female
Unknown.

Discussion
We examined the holotype of Chrysidea pumiloides and voucher specimens identified as C. pumiloides.As a result, four different species were recognized: C. pumiloides and three different species including two new species, C. merina sp.nov.and C. vazimba sp.nov.The other new species, C. rioae sp.nov. is the third species of the genus Chrysidea without TFC.The finding of three new species from the limited number of specimens implies higher species diversity of Malagasy Chrysidea.Specimens of Chrysidea are not so abundant in museum collections, especially in recently collected material.Among them, the collections of Seyrig and Saussure, which were amassed around 50-100 years ago, greatly contribute the current understanding of Malagasy fauna.Compared with the past, their habitat should be restricted because more than 80-90 % of Madagascar's original vegetation is estimated to be destroyed (Fisher & Robertson 2002;Ichino 2007).Recently the decline of large trees and the forest drying have been observed in the Berenty reserve, the type locality of C. rioae sp.nov.(Ichino 2007).The hosts of the five species treated in this study are unknown, this is actually the case with most species of Chrysididae.Further field investigation is needed to understand their life history and habitat requirements.
Abbreviations for morphological termsF1-F11 = flagellomeres 1 to 11 F1 l/w = relative length of the length of flagellomere 1 compared to its width MOD = mid ocellar diameter MS = malar space, the shortest distance between the base of mandible and the margin of compound eye OOL = oculo-ocellar line, the shortest distance between the lateral ocellus and the compound eye P = pedicel PD = puncture diameter POL = the shortest distance between posterior ocelli S1-S3 = metasomal sterna 1 to 3 T1-T3 = metasomal terga 1 to 3 TFC = transverse frontal carina
EtymologyChrysidea vazimba sp.nov. is named after the name of the first inhabitants of Madagascar, according to popular tradition.