Rhoptromeris leptocornis, Costa Baião & Forshage, 2018

Costa Baião, Guilherme & Forshage, Mattias, 2018, Revision of the West Palaearctic species of Rhoptromeris Förster, 1869 (Hymenoptera: Figitidae: Eucoilinae), Journal of Natural History (J. Nat. Hist.) 52 (17 - 20), pp. 1201-1224 : 1216-1218

Rhoptromeris leptocornis sp. nov.

( Figure 3e,f )

Diagnosis

Species with characteristic colour pattern of dark brown head, mesonotum and scutellum contrasting with light or chestnut brown remainder of mesosoma ( Figure 3e,f ). Colour contrast less evident in very dark or pale specimens. Body length 1.0– 1.5 mm, marginal cell elongate, vein 2r somewhat longer than Rs. Distinguishable from other European species by the very long antennae which are longer than the body on females and twice as long as the body on males, large scutellar plate and presence of posteroventral cavity on metapleuron. Studied specimens from Turkey and Greece were smaller and paler than those from other areas.

Description

Antennae filiform, elongate, approximately 1.3× body size in females, 2.0× in males. Female antenna 13-segmented with scape and pedicel yellow or light brown, first two flagellomeres yellow, flagellomeres 3–13 light brown or brown. Flagellomeres several times longer than wide and subequal in length, except for first flagellomere somewhat shorter. Indistinct club of 7–8 segments only slightly wider than pre-club flagellomeres, rhinaria often hard to distinguish. Male antenna 15-segmented with scape, pedicel and first two flagellomeres yellow or light brown, flagellomeres 3–15 gradually darker until light brown to brown. Second flagellomere modified, longer than neighbour articles, somewhat flattened, moderately curved. Compound eyes and ocelli large.

Mesonotum, smooth, glabrous, moderately arched. Pronotal plate with lateral bridges, foveae confluent in the middle forming a transverse furrow ( Figure 2b ). A small lateral incision on either side of the furrow, which could possibly be mistaken for a laterally open fovea as in the majority of other genera of Eucoilinae .

Scutellar plate elevated, large, drop-shaped, posteriorly protruding to hind margin of scutellum. Dorsal surface flat to slightly concave, with a distinct margin, a few scattered setae and a very large posterior glandular pit. Scutellar foveae relatively narrow, shallow ( Figure 6c ). Lateral bars smooth. Dorsal scutellar surface smooth or longitudinally striate, striation stronger posteriorly. Dorsal surface with a line of setae along its rim, separated from lateral surface by a carina. Lateral surface smooth. Scutellum strongly sloping posteriorly.

Mesopleural line present. Lateral surface of metapleura glabrous, except for 2 or 3 long setae on dorsal region. Anteroventral cavity round, filled with hair, sometimes completely enclosed by sclerite. Surface smooth except for oblique ridge running anterodorsally from approximately one-third the height of posterior margin. Posterior margin with a circular incision below the ridge (posterior incision of metapleura ( Figure 1c ). Area around incision often somewhat depressed. Posterior corner of metapleura pointed, sometimes slightly upcurved.

Propodeum more or less pubescent laterally, tuft of hair behind posteroventral metapleural cavity. Propodeal carinae slightly converging dorsally, sometimes weakly arched on ventral portion.

Metasoma chestnut brown to dark brown, darker on its posteroventral half. Hairy ring often incomplete dorsally, dense in females, sparse in males.

Legs long and slender, yellow, sometimes light brown. Metacoxae elongate, with a small posteroproximal tuft of short hair.

Wings relatively narrow, hyaline, pubescent, apex rounded with a rather long hair fringe. Marginal cell closed, narrow, elongate, at least twice as long as deep, vein 2r somewhat longer than Rs. Venation yellow or light brown, accessory veins visible as spectral veins.

Etymology

From the greek ‘lepto-’ meaning thin, slender, and the latin ‘-cornis’, horns. Refers to the thin, elongate antennae.

Distribution

Western Palearctic: specimens seen from Canary Islands, Croatia, France, Germany, Greece, Madeira archipelago, Norway, Spain and Turkey. A large number of specimens were collected at the Macaronesian islands, while only isolated individuals were seen from the continent.

Holotype

Female: MADEIRA ISLAND – Portugal, Ribeiro Serrao, Proj. Meia Serra, 6 October 2004, Plant: Erica scoparia, No beat: 2(40) ( MNCN).

Paratypes

(46 females, 30 males): CANARY ISLANDS: TENERIFE, El Batan, 26 October 1996, M . Báez (1 male, coll Koponen); La Laguna, Anaga Mts, Las Mercedes-Wald , 889 m, 28.5303°N 16.2878°W, 16 October 2008 (1 female, OLML); Puerto de la Cruz, Taoro, 11 December 1986, M . Koponen (1 male, coll Koponen) . MADEIRA ISLAND: Funchal, Curral das Romeiros, (500–600 m), 8 December 1991, M. Koponen (1 female, coll. Koponen); Funchal, Curral das Romeiros, (500– 600 m), 22 December 1995, M . Koponen (1 female, 1 male, coll. Koponen); Funchal, Old Monte Gardens, 550 m, 5 November 1996, M . Koponen (28 females, 20 males, coll Koponen); Funchal, Palheiro Ferreiro, (550–600 m), 22 December 1995, M . Koponen (1 female, 3 males, coll. Koponen); Funchal, Quinta do Pomar , (600 m), 22 December 1995, M . Koponen, (5 females, 1 male, coll. Koponen); Jardim da Serra , 10 December 1991, M . Koponen , (1 male, coll. Koponen); Monte, (550–750 m) 17 December 1994, M . Koponen (3 females, 2 males, coll. Koponen); Monte, (600 m) 8 November 1996, M . Koponen (1 female, coll. Koponen); Monte, (600 m) 3 November 1996, M . Koponen (2 females, coll. Koponen); Ribeiro Serrao, 6 October 2004 (3 females, MNCN) .

Additional material

CROATIA: Zadar, Borik , 15 July 1961, Stellan Erlandsson (1 male, SLU) . GREECE: Kerkini Lake National Park, yellow pan trap, Megalohori site, 24–29 August 2008, Gordon Ramel (1 female, NHRS) ; NORWAY: Oslo, Ekebergskråningen , 29 May–27 June 2007, A . EndrestØl / Lars Ove Hansen (1 female, ZMUN) ; SPAIN: Alcoletge, Lleida, 31T CG01, 160 m 19 July 2007 ‘ Sweeping on grasses and flowering vegetation, lowland Populus riparian forest’ Leg Antoni Ribes (2 males, coll Ribes); La Mitjana, Lleida 31T CG01, 145 m, 22 June 2007 ‘ Sweeping on flowering Dorycnium pentaphyllum ’ Leg Antoni Ribes (1 male, coll Ribes) ; TURKEY: Side . 1–12 June 1992 Gardens and pasture. Light trap Leg Gösta Gillerfors (1 female, MZLU) .

Biology

Specimens were collected between June and August on the continent and from October to December on Madeira and Canary Islands, at elevations ranging between 89 and 889 m. In Madeira, individuals were swept from Erica scoparia , Origanum, Quercus and Vaccinium , while in Spain specimens were captured on Dorycnium pentaphyllum and among grasses and flowering vegetation in a riparian forest. Probably a parasitoid of Chloropidae (Diptera) , as are other Rhoptromeris species.

Figures

Figure 1. Scanning electron microscopy (SEM) images of the metapleura of (a) Rhoptromeris dichromata sp. nov., (b) R. koponeni sp. nov., (c) R. leptocornis sp. nov. and (d) R. macaronesiense sp. nov. Vertical arrows point to the anterior cavity of the metapleura (present in a, b and c, absent in D) while diagonal arrows indicate the posterior incision of the metapleura (present in c and d, absent in a and b).

Figure 2. Scanning electron microscopy (SEM) images of the pronotal plate of (a) female Rhoptromeris dichromata sp. nov., (b) male R. leptocornis sp. nov., (c) female R. koponeni sp. nov., and (d) female R. macaronesiensis sp. nov.

Figure 3. Habitus of Rhoptromeris dichromata sp. nov. (a: female, b: male), Rhoptromeris koponeni sp. nov. (c: female, d: male), Rhoptromeris leptocornis sp. nov. (e: female, f: male) and Rhoptromeris macaronesiesis sp. nov. (g: female, h: male).

Figure 6. Scanning electron microscopy (SEM) images of the scutellum of (a) female Rhoptromeris dichromata sp. nov., (b) female R. koponeni sp. nov., (c) male R. leptocornis sp. nov., and (d) female R. macaronesiensis sp. nov.