Sesioctonus longinoi Sharkey and Briceño, 2005

Briceño, Michael J. Sharkey Rosa A., 2005, Review of Sesioctonus Viereck (Hymenoptera: Braconidae: Agathidinae) from Colombia with descriptions of five new species, Zootaxa 1002 (1002), pp. 45-58 : 49-52

Sesioctonus longinoi Sharkey and Briceño sp. n.

FIG. 1f

Diagnosis. This is a difficult species to distinguish from other species. Many of the characters that are used in the key are variable within this species, e.g., (RS+M)a vein of fore wing varies from complete, to almost complete with a small break at midlength, to mostly absent; scutellar depression varies from smooth, lacking longitudinal carinae, to with weak longitudinal carinae; median areola of metanotum smooth to moderately rugose; and the median tergite of the first metasomal segment may be with or without a pair of lateral longitudinal carinae. The coloration of all included specimens is pale yellowish orange with black head, pronotum, and most leg segments. The occiput has tubercles and it is excavated. The hind tibia has many apical spines (18–22). Otherwise, most characters are variable and specimens must be taken through the key.

Notes: In the second author’s revision ( Briceño 2003), members of this species would mostly key to S. diazi , and two paratypes of S. diazi are included in the type series of S. longinoi . See discussion under S. diazi . The fact that S. longinoi is here split from the concept of S. diazi renders S. diazi rather uniform and easy to diagnose. S. longinoi is rather heterogeneous. Though the coloration of the included specimens is rather uniform, many characters, that are otherwise reliable to distinguish species of Sesioctonus , are variable within the species, as it is here delimited. There are also distributional anomalies that cast doubt on the validity of the species. Though most specimens have been collected in lowland areas, there are three paratypes captured at 1,450 meters in Costa Rica. No other species of Sesioctonus has such a wide altitudinal range. Though we doubt that all of the specimens in the type series constitute one species we have not been able to find any reliable suite of characters to make a better estimate. This is likely a rapidly evolving lineage with weak morphological indications of species status. More data are needed to arrive at a satisfactory answer, if there is one.

Description.

♀. Length. Length of body, excluding ovipositor, 7.3–8.0 mm.

Head. Antenna with 32 (29–33) flagellomeres. Interantennal space without sharp longitudinal keel. Antennal sockets not excavated. Face without median longitudinal carina. Gena not expanded posteroventrally. Occipital tubercles present. Occiput excavated, vertical surface of occiput starting immediately posterior to lateral ocelli (Fig. 16). Mandible concave. Outer tooth of mandible longer than inner tooth. Maxillary palpus with 4 palpomeres. Third and fourth labial palpomeres fused. Mesosoma . Subpronope elongate. Scutellar depression smooth, lacking longitudinal carinae (some paratypes with weak longitudinal carinae). Scutellum convex. Median areola of metanotum smooth (moderately rugose in some paratypes), with median longitudinal carina posteriorly, and with lateral carinae present and meeting posteriorly (not meeting in many paratypes). Propodeum convex. Median longitudinal carina of propodeum present at anterior and posterior borders. Epicnemial carina sharp, complete, bilobed ventrally (Fig. 3). Fore tibial spines absent. Mid tibia with 10 (8–11) spines. Hind tibia with 20 (18–22) spines. Hind femur 3.4 times as long as wide. (RS+M)a vein of fore wing incomplete in holotype (varying across the species from complete, to with a small break, to mostly absent). 3RSa vein of fore wing present, 2 nd submarginal cell of fore wing sessile. 2­1A vein of hind wing tubular. CUb vein of hind wing present but not tubular. Hind wing with 4 (4–5) hamuli. Metasoma. Median tergite of first metasomal segment with pair of weak lateral longitudinal carinae (relatively strong to very weak in the type series). First metasomal median tergite without depression posterad spiracle. Length: width ratio of first metasomal median tergite 0.94. Ovipositor length 7.7 mm.

Color. Yellowish­orange and black. Black as follows: Head black except apical maxillary palpomeres pale yellow, propleuron and anterior margin of pronotum, all legs except base of hind coxa, apical two metasomal terga, ovipositor sheath; wings evenly infuscate. (Variation: fore tarsus and apex of fore tibia pale yellowish orange; fore tibia orange basally; mid and hind coxa entirely yellowish orange to entirely black; hind femur mostly orange except basally; apical 1/8 of mid femur yellowish orange; metasoma entirely yellowish orange).

♂: Only one male specimen known. It is essentially as in the female (above) but has slightly more black color, i.e., metacoxa entirely black, metasomal terga 5 to apex black.

Etymology. Named after John (Jack) Longino, myrmecologist and coordinator of the ALAS (Arthropods of La Selva) biodiversity project, for his many contributions to neotropical natural history studies.

Material examined. Holotype. COLOMBIA.: Cauca, PNN Gorgona: ♀, Antigua Laguna , 2º58'N 78º11'W, 70m., Malaise, 30.xi–18.xii.2000, H. Torres Leg. M.1089, (IAvH).

Paratypes: ♀, Alto el Mirador , 2º58'N 78º11'W, 180m ., Malaise , 3–16.viii.2000, H. Torres Leg., M.587, (IAvH) . ♀, Amazonas, PNN Amacayacu, Matamata , 3º41'S 70º15'W, 150m , Malaise 1, 17.ix–1.x.2001, D. Chota Leg, (IAvH) . ♀, Mancora , 2º58'N 78º11'W, 60m ., Malaise 3–18.i.2001, H. Torres Leg., M.1235, (IAvH) . ♀, Mancora , 2º58'N 78º11'W, 60m ., Malaise , 18.vii–3.viii.2000, H. Torres Leg., M.584, (IAvH) . ♂, Mancora , 2º58'N 78º11'W, 60m ., Malaise , 3–16.viii.2000, H. Torres Leg., M.586, (IAvH) . 3♀, Valle del Cauca, PNN Farallones de Cali , Anchicaya, 3º26'N 76º48'W, 650m ., Malaise , 19.xii– 2.i.2001,14– 28.viii.2001, and 31.x–13.xi.2001, S. Sarria Leg., M.2887, (IAvH, HIC) .

PANAMA: ♀. P.N. Darien, Pirre, Est. Rancho Frio , 80m ., 7–16.xi.2000, Canbra and Santos ( MIUP) . COSTA RICA: Heredia: ♀, Est. Biol. La Selva , 50– 150m ., 10º26’N 84º01’W, May 1993, INBio­OET (also paratype of S. diazi ). ♀, Est. Biol. La Selva , 50– 150m, 10º26’N 84º01’W, August 1993, INBio­OET (also a paratype of S. diazi ). Puntarenas : 2♀, Buenos Aires, Estación Altamira, Sendero Los Gigantes. 1450m., Malaise, 4 ENE­3 FEB 2000, D. Rubí. L_S_331700_572200 #55201. ( HIC, INBio) . ♀, Buenos Aires, Estación Altamira, Sendero Los Gigantes , 1450m.,15 JUL–15 AGO, 2000. D. Rubí, Malaise, L _S_572200_331700 #57880 (INBio) . ♀, Golfito, Estación Agujas 300m ., 01– 30 OCT, 2000, J. Azofeita, Malaise, L_S_526550_276750 #60078 ( HIC) . ♀, Golfito, P.N. Corcovado, Sendero a Sirena , 100m ., 15 MAY­15 JUN 2000, J. Azofeifa, Malaise, L_S_276500_514200 #56671 (INBio). ♀, Golfito, P.N. Corcovado, Send. a Sirena , 100m ., AGO 2000, J. Azofeifa, Malaise, L _S_514200_276500 #58151 (INBio). Limón : ♀, Valle de la Estrella, Reserva Biol. Hitoy Cerere, Sendero Toma de Agua , 100– 140m ., 17 NOV– 17 DIC, 1999, F. Umaña, Malaise, L_S_184600_643400 #54940 ( HIC) . ♀, A.C.L.A.C, Central Res. Biol. Hitoy Cerere, Send. Toma de Agua , 100– 140m ., 17 FEB–17 MAR, 2000, F. Umaña, Malaise, L_N_184600_643400 #55287 ( HIC) . ♀, Cartago, P.N. Barbilla, R. Dantos, 0.400 Kms aguas arriba margen izq. 500– 600m . 9 DIC 1999 ­ 8 ENE 2000, E. Rojas, Malaise, L_N_218100_593600 #54385 ( HIC) .

Distribution. From Colombia north to Costa Rica mostly in lowland wet forests, except for some specimens from Costa Rica that were captured at 1,450 meters.