Arotes ucumari Castillo & Saeaeksjaervi

Castillo, Carol, Saeaeksjaervi, Ilari E., Bennett, Andrew M. R. & Broad, Gavin R., 2011, First record of Acaenitinae (Hymenoptera, Ichneumonidae) from South America with description of a new species and a key to the world species of Arotes Gravenhorst, ZooKeys 137, pp. 77-88 : 81-84

Arotes ucumari Castillo & Saeaeksjaervi sp. n.

Type locality.

Peru, Dept. of Cusco, Manu National Park, Cosñipata valley, San Pedro, 13°02'58"S, 71°32'13"W, 1500 m elev., C. Castillo leg., 20 September 2007.

Type specimen.

Holotype female, pinned. Original label: "Peru, CU, San Pedro, 13°02'58"S, 71°32'13"W, 1500 m, Malaise trap, 20.ix.2007, C. Castillo". UNSM.

Diagnosis.

Arotes ucumari sp. n. (Fig. 4) can be distinguished from all other described Arotes spp. by combination of all the following characters: 1) hind tibia black; 2) scutellum yellow; 3) antenna without a medial light coloured band; 4) hind femur ventrally not or only slightly swollen subapically.

Arotes ucumari sp. n. is readily distinguished from other New World species of Arotes (except Arotes facialis ) on account of its totally black antennae (character 3). It differs from Arotes facialis in that it has more extensive yellow colouration on the meso- and metasoma ( Arotes facialis is almost completely black). In addition, the propodeal carina tion of the three neotropical species is different (Figs 1-3). The area superomedia of Arotes facialis is hexagonal to subcircular whereas that of Arotes ucumari is irregularly octagonal (Fig. 2). In coloration, Arotes ucumari is similar to Arotes pammae Gauld (Fig. 5) but may be separated from that species by the black antennae, smoothly rounded first sternite of metasoma and the propodeal carination (in Arotes ucumari , the anterior transverse carina joins the area superomedia at its upper half and the shape of the area superomedia is irregularly octagonal).

Description.

Female.

Habitus in Figure 4. Lower face broad, inner margins of eyes ventrally divergent; frons concave, smooth; antenna with 34 flagellomeres; antenna about as long as fore wing. Pronotum with striae directed to hind corner of pronotum, middle of pronotum just dorsoposterior to pronotal trough impunctate; mesoscutum with lobes sparsely, coarsely punctate, closely punctate on front side; scutellum more closely punctate than mesoscutum; mesopleurum anteriorly, ventrally coarsely punctate; metapleurum coarsely, closely punctate but, above submetapleural carina punctures are separated by more than their diameter; propodeum with area superomedia clearly delineated, almost hexagonal anteriorly, posteriorly narrowed, so that it is irregularly octagonal (Fig. 2), posterior border of area superomedia concave; anterior transverse carina joining area superomedia at its upper half; lateral longitudinal carina only delineating area externa and area posteroexterna; area petiolaris confluent with area posteroexterna. Fore wing length 14 mm, wing without areolet, with cross vein 2rs-m (or 3rs-m, depending on interpretation) distal to 2m-cu. Hind femur ventrally with a slight subapical swelling. First metasomal sternite with projection smoothly rounded; ovipositor projecting beyond apex of metasoma by about 1.9 times length of hind tibia.

Yellowish species with black marks. Head light yellow with temple, frons and inner margin of occiput black; antenna black except infuscate tip on last flagellomere. Mesosoma mostly light yellow with dorsal and hind margins of pronotum black, mesoscutum black with yellow marks on lateral and hind regions of central lobe, U-shaped mark in dorsal view, lateral sides of mesoscutum, scutellum and metanotum also yellow, hind margin of mesopleurum, mesosternum and anterior half of propodeum black. Wings slightly yellowish, with apex broadly infumate, pterostigma and veins black. Fore and mid legs with light yellow on dorsal surfaces of trochanters and femora, most of tibiae and all tarsi infuscate; hind leg black with yellow marks on lower half of coxa, two oval yellow marks on dorsal and lateral sides of coxa, most of trochanter and ventral half of femur light yellow. Metasoma black, tergites 1-2 with broad yellowish marks close to hind margin, tergite 3 almost entirely black, tergites 4+ with hind margins and lateral spots light yellow; subgenital plate infuscate with upper margin yellowish; ovipositor orange, ovipositor sheaths black with dull yellow tip.

Male.

Unknown.

Biology.

The host of Arotes ucumari sp. n. is not known. North American Arotes species have been reared from Melandrya (Melandryidae), Leptura (Cerambycidae) and Tomoxia (Mordellidae) ( Townes and Townes 1960; Gauld 1991).

Ecology.

The type locality is in a primary forest at the south east limit of Manu National Park. On the eastern slopes of the Andes, this altitude (1500 m) is considered as a major ecotone between the humid montane forest and the premontane forest belt ( Young and León 1999). It differs from both highland Andean and lowland Amazonian vegetation formations. The Andean foothills of Manu-Tambopata are considered to be a super-humid region ( Killeen 2007). The annual precipitation in 2007, when the holotype was collected, was 3158 mm. The mean maximum and minimum temperatures were between 21,6 and 11,3 degrees Celsius ( SENAMHI, National Service of Meteorology and Hydrology of Peru).

Etymology.

Ucumari is the quechuan name for the only South American species of bear, Tremarctos ornatus , the Spectacled Bear. Just as is possible in the case of the Acaenitinae parasitoid wasps, the tremarctine bears reached the New World via the Bering Strait, and expanded their range southwards into North and South America. By naming the new species as Arotes ucumari we hope to draw attention to the conservation of both of these rare tropical Andean species.

The status of Phaenolobus ( Acoenitus ) moiwanus Matsumura, 1912

During the process of comparing specimens to verify the new species status of Arotes ucumari , examination of material of Arotes albicinctus and its subspecies Arotes albicinctus moiwanus at NHM and CNC revealed differences that could indicate that these two forms may represent two distinct species. Since Uchida (1934), Phaenolobus ( Acoenitus ) moiwanus Matsumura, 1912 has been regarded as a subspecies of Arotes albicinctus (Gravenhorst, 1829) (e.g. Townes et al. 1965; Yu and Horstmann 1997). Our examination found the differences listed in Table 1.

In most ichneumonid species in which subspecies are recognized, the only indicator of subspecies is colour, not sculpture. For example, Campoplex sugiharai sugiharai (Uchida), Campoplex sugiharai australis Momoi and Campoplex sugiharai okinawensis Momoi (see Momoi 1970). Such a major difference in the sculpture of the frons (striate versus sparsely punctate) generally indicates two species. We believe that the sculptural differences of the frons correlated with major colour differences of the scutellum and propodeum are clear indicators that Arotes albicinctus and Arotes moiwanus are two distinct species. Arotes moiwanus stat. n. is hereby recognized as a valid species. We have not seen males of Arotes moiwanus but we expect these characters to remain valid.