Lubomí Masner.
Remarks on Sceliotrachelus Brues and Allied Genera (Hymenoptera, Platygasteridae.
Psyche 71:8-11, 1964.

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REMARKS ON SCELIOTRACHELUS BRUES AND
ALLIED GENERA
(HYMENOPTERA, PLATYGASTERIDAE)*
BY LUBOMI'R MASNER
Department of Insect Pathology, Institute of Entomology Czechoslovak Academy of Science, Prague
In 1908 Brues (in Wytsman, Genera Insectorum) described a peculiar new genus Sceliotrachelus Brues from South Africa. At the same time he erected the new subfamily Sceliotrachelinae to comprise the single genus Sceliotrachelus Brues. Having some doubts on the phylogenetic relationships of
this curious genus (and subfamily as
well) Brues decided to place it in Scelionidae between the subfamilies Telenominae and Baeinae. He says: "The species upon which this genus is based is without doubt one of the most remarkable insects -
which I have ever seen. For some time I was undecided to what family it could be referred, but after much thought, I believe that it shows the greatest affinity to certain Telenominae or Teleasinae, although the relationship is by no means close. The large pronotum and the small mesoscutum are unique in this and related families, but the form and insertion of the antennae, and the configuration of the abdomen undoubtedly denote relationship to either the Ceraphronidae, Scelionidae or Platygasteridae". Brues established his new subfamily first of all on the large pronotum and on the morphology of the wings. Kieffer (1926) did not recognize the subfamily Sceliotrache- linae and included Sceliotrachelus Brues among the Platygasterinae ( tribe Platygasterini) . Contrary to Brues ( 1908) he emphasized that the shape of the scutellum in Sceliotrachelus Brues exhibits a close relationship with Chalcididae (!) rather than with families mentioned by Brues. So far as known to the author there is no study referring to this problem except for the two mentioned above. The description (and the figure as well) does not give a clear idea of the relationships of the genus.
We have had the opportunity of
examining the male paratype of Sceliotrachelw braunsi Brues. Un-
fortunately, we cannot agree with either Brues or Kieffer regarding the position of this genus. After examining the paratype we have no doubt that SceZio~rachelus Brues belongs to the family Platygasteridae. There is no evidence of relationship either with the Scelionidae or even the Ceraphronidae. Kieffer's (1926) conjecture on the rela- *Manuscript received by the editor September 8,1963. 8




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19641 h e r - Sceliotrachelus 9
tionship or similarity with the Chalcididae is evidently wrong. It is doubtful if Kieffer actually saw any specimens. In 1959 Szab6 established a new tribe within the Platygasteridae, the Amitini, to comprise the following genera: Amitus Hald., Fidiobia Ashm., Pulchrisolia Szab6 and Isolia Forst. The genus Sceliotrachelus Brues exhibits a striking relationship with some of these genera (par- ticularly with Isolia Foi-st.) so we are sure it should belong there. From the nomenclatosial point of view we are forced to change the name of the tribe as follows:
Sceliotrachelini Brues, I 908 - NEW STATUS (= Amitini Szab6, 1959 - NEW SYNONYMY)
As Sceliotrachelini Brues was proposed originally as a subfamily of Scelionidae in 1908 it becomes automatically the new name of the group. The type genus is consequently Sceliotrachelus Brues. The tribe Sceliotrachelini, according to our conception, should be- long to the subfamily Inostemminae. We suggest it to be the most apo~norphous tribe of Inostemminae, where the subcostal vein is tending to disappear gradually. In Fidiobia Ashm. (in all species we have seen, except in brachypterous F. pronotata Szab6) there is a very short subcostal vein, knobbed apically. In Platygastoides Dodd, at least in P. mirabilis (the type of genus) the subcostal vein is still knobbed apically, but as a whole, the vein is tending to disappear ( Fig. 2). In Amitus Hald.
( = Zacrita Forst., Passalida Breth.)
there is sometimes a trace of vein but this is never knobbed apically. In Isolia Forst. and Sceliotrachdus Brues the fore wing is perfectly veinless. The typical character of Sceliotrachelini is the antenna1 club in the female, which is abrupt, massive and 3-jointed (in Am'tus Plaid. the club is rather solid, the sutures obsolete). The gastei- in
this tribe is very stout, resembling that of the subfamily Telenominae (Scelionidae), not casinated ventrally (there is no impressed sub- marginal ridge) at most slightly sharpened at sides. The curious Platygastoides Dodd is included also in this tribe. It combines some characters of Fidiobia Ashrn. and Isolia Forst. Figures 2, 3 and 4 illustrate this peculiar insect. Genus Sceliotrachelus Bi-ues
Sceliotrdelus Brues, 1908, in Wytsman, Genera Insectorurn, 80:13. Pulchnsolia Szab6, 1959, Ann. Hist. - Nat. Mus. Nat. Hung., 51 :395 - NEW SYNONYMY.
The male paratype of Sceliotrachelus braunsi Brues was examined. Labels : "Algoa bay Capland, I I. 10.96 ; Sceliotrachelus braunsi Brues, Paratype". Right wing and some legs torn off.



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19641 Masner -- Scdiotrachelus I I
The description should be completed and corrected. There are no "tufts of long yellow hairs" on the propodeum which Brues com- pares with those of some myrmecophilous beetles (e.g. Lomechusa Gr.). There is a compact hyaline membrane, just as in Isolia Forst., Fidiobia Ashm. and Platygastoides Dodd. Consequently, there is no reason to suggest that Sceliotrachelus Brues is a myrmecophilous in- sect. The long dense hairs are found on the base of first as well as second tergite of the gaster.
The figure in Brues (1908) is, as a whole, not very exact and therefore we prefer to give a detailed drawing of the insect here (Fig. 1).
Pulchrisolia Szab6 becomes inevitably a synonym of Sceliotrachelus Brues. The holotype of Pulchrisolia maculata Szab6 (a female from Shirati, East Africa) was examined and found to belong to Scelio- trachelus Brues.
So far no more material is available. We prefer to keep both - braunsi Brues and maculatus Szab6 - as independent species. The necessary nomenclatorial formality is as follows - Scelio- trachelus maculatus (Szabb, I 959) - new combination ( = Pul- chrisolia maculata Szab6, I 959).
The author is obliged to Dr. Howard E. Evans (Museum of Comparative Zoology at Harvard College, Cambridge, Mass.), Dr. Janos B. Szab6 (Hungarian State Institute of Hygiene, Budapest) and Dr. Edgar F, Riek (Commonwealth Scientific and Industrial Research Organization, Canberra A.C.T.) for the kind loan of the necessary type material.
BRUES, C. T.
1908.
In Wytsman: Genera Insectorum, Scelionidae, fasc. 80. KIEFFER, J. J.
1926. Scelionidae. Das Tierreich, 48 :606. SZABO, J. B.
1959.
Notes on the New Tribus Amitini with the Descriptions of a New Genus and Some New Species of the Arctogaea (Hymenoptera, Proctotrupoidea. Platygasteridae). Ann. Hist. Nat. Mus. Nat. Hung., 5 1 :389-396.
EXPLANATION OF PLATE 1
Fig. 1. Sceliotrachelus braunsi Brues, male paratype. Fig. 2. Platygastoides mirabilis Dodd, female. Fig. 3. Platygastoides mirabilis Dodd, female, head, Fig. 4. Platygastoides mirabilis Dodd, female, antenna.



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