A New Parasite of the Swallow-tailed Butterfly

47

A NEW PARASITE OF THE SWALLOW-T AI LED BUTTERFLY.

BY CLAUDE MORLEY, F.E.S., F.G.S., F.Z.S.

IN order to illustrate the unusual numbers of Swallow-tailed Butterflies migrant to Suffolk that year, larvae and chrysalides and imagines of Papilio Machaon, along with their pupal parasites the Irhneumonid Dinotomus lapidator, Fab. and doubtless hyperparasitic Chalcid unnamed, were exhibited at the October Meeting of this Society in 1945 (Proc. v, p. xcii) at Southwold Town Hall.

Neither of these Hymenoptera appears at all frequent in Britain (cf. our Member P. B. M. Allan's 1943 " Moths," p. 146) ; and, consequently, can be accused of curtailing the Butterfly's iocalisation in England. Nor, we now find, are these the only ills that P. Machaon is heir to ; for a third Hymenopterous parasite has just come to light that deposits its eggs in those of the same host, the contents of which the emergent grubs devour. This is one of the Proctotrypidae, hitherto undescribed, which I characterise as follows.

ANAGRUS NIVEISCAPUS,

sp.nov.

Prothorax reaching backwards to base of wings; terebraemitted from anal apex ; venation sparse and normal (nec Helorinae) ; hind wing with no lobe before the anal angle (nec Emboleminae, &c) ; scutellum neither discally bisulcate nor basally constricted (nec Ceraphrontinae) ; antennae emitted close to mouth and abdomen acutely margined laterally (nec Belytinae, &c) ; front calcaria bilobed, antennae at most 12-jointed, alar nervures distinct (nec Platygastrinae) ; wings elongately ciliate and hind ones narrow.—Subfamily MYMARIN/E. All the tarsi with only four joints, antenna of 2 9-jointed with apical club entire, abdomen sessile, front tarsi not longer than tibiae nor thorax elongate, wings not parallel-sided with their disc not very coarsely pilose, abdomen elongate and metathorax declivous, terebia shortly exserted.— Genus ANAGRUS, Hai. (Entom. Mag. i, p. 369).

Dull red with scutellum and eyes hardly paler ; head and abdomen indefinitely infuscate ; wings not lutescent ; antennal scape pure pearly white. I.ength, .92 (or circa J mm.) ; expan. alarum, .05 lin. 2 only.— Species niveiscapus, nov.

This is pretty surely Haliday's A. albiscapus, which has never been described and is merely mentioned, without locality, by Walker (Ann. Nat. Hist. xviii, 1845, p. 51); I discovered no indicated type of the MS. name when examining Haliday's collection at Dublin Museum (Entom. 1913, p. 259). I know no other Mymarid with conspicuously snow-white scape; but do not adopt Haliday's name in case his species prove different, and so cause confusion. One of this genus has been raised from the eggs of the Moth Dasychira pudtbunda, L., on the Continent;

48

A NEW PARASITE

and a capital account of another is given by Prof. Heymons (Deut.

Ent. Zeit. 1908, p. 141) as destroying eggs of the British Dragonfly Calopteryx virgo, L., which host seems shared with Anagrus hydrophilus, Ashm., in Turkestan.

Five (very possibly others escaped) co-types of Anagrus niveiscapus, Morl., were found to have emerged at Lowestoft on 15 July through two subcircular holes in the lateral surface of a single egg of Papilio Machaon by our Lowestoft Secretary, Percival J. Burton esquire, who had discovered it along with other fertile ova, when we were collecting together on 18 June 1950 at Catfield marsh in the Norfolk broads. I suspect them of being unc.ommon because nothing but a normal Caterpillar emerged from each egg of a day's collecting, taken in 1918 at Horning Ferry by Dr. Vinter and me, as well as 1938 at Wicken Fen by Dr. Blair.

Ischnodes sanguinicollis, Pz.—Mr. Fred Fox of Coddenham, who died in 1897, told me that he had captured three specimens of this rare Click Beetle in that village during 1896 (Coleop.

Suffolk 1899, 68) and there is a very ancient and bad specimen in the cabinet of a possibly local collector that I purchased in an Ipswich shop about the same period : which are all known from our County. On 24 June 1950 another was beaten by Mr. Jim Burton from a Scots Fir-tree on the highest point of Fritton Warren at 2 p.m., which has the thorax unusually dull red.

The species has not been recorded elsewhere from north of Oxfordshire since 1835, when Stephens gives " Norfolk " as a locality for his synonymous Megapenthes (Trans. Norf. Nat. Soc. 1893, 477). There at Fritton also occurred between 21 May and 24 June Coccinella 4-punctata, Pont., an extension of fifteen miles north from Blythburgh Wood (Trans, iv, 247); Cantharis paludosa ; and, as last year (page 6), Corymbetes aeneus and Pissodes notatus.—CLAUDE MORLEY. IMPORTED LOCUST, NEW TO SUFFOLK.—A Locust, measuring three inches in length, was found on the night of 2 February 1950 in the back kitchen of an Ipswich house. It is thought to have been brought in a cauliflower (Local Paper, 4 Feb).

This was a house in Dales-view Road there, where vegetables had just been bought, doubtless containing it. The species is Melanoplus femur-rubrum, a native of North Africa ; and the specimen now in our Hon. Secretary's collection.—S. BEAUFOY ; 4 March.

[Where this $ remained sluggish, became moribund, and on 20 March died in temp. 55-65°.—Ed.]