Sergey tzeltal Martinez & Zaldivar-Riveron

Martinez, Juan Jose, Lazaro, Rubi Nelsi Meza, Pedraza-Lara, Carlos & Zaldivar-Riveron, Alejandro, 2016, Sergey gen. n., a new doryctine genus from temperate forests of Mexico and Cuba (Hymenoptera, Braconidae), ZooKeys 589, pp. 143-164 : 152-156

Taxon classification Animalia Hymenoptera Braconidae

Sergey tzeltal Martinez & Zaldivar-Riveron sp. n. Figs 20-23, 24-29

Diagnosis.

This species is similar to Sergey tzotzil , but it can be distinguished from the latter species by the colour pattern of the white band on the female antenna. In Sergey tzeltal , the white band is either apical or subapical and is composed of at least two entire whitish flagellomeres, usually more, with at most three apical flagellomeres brown. In Sergey tzotzil , the white band is subapical and consists only of the lighter color on the articulation between the 19th and 20th flagellomeres, and with the five apical flagellomeres brown.

Description.

Body length 3.1 mm (Fig. 20), fore wing 2.7 mm; ovipositor sheaths 1.5mm. Colour: head uniformly brown, antenna brown, gradually darkening towards apex, except for a subapical white band composed of 2-4 flagellomeres (apical in Oaxaca population composed of 6-8 flagellomeres, see below) (Figs 24, 26). Mesosoma uniformly dark brown, except for a slightly lighter area on the median area of mesoscutum. Metasoma brown. Legs light brown, except fore and middle coxae, trochanters and trochantelli and hind trochantellus, which are pale yellow; hind coxa and apical three fourths of hind femur dark brown. Wings hyaline; pterostigma and veins brown. Ovipositor sheaths brown.

Head: 0.8 times as high as wide in anterior view (Fig. 21), and 0.7 times as long as wide in dorsal view (Fig. 22). Clypeus, face, frons and vertex smooth and polished; temple smooth. Eye 1.3 times higher than wide. Malar space height/eye height ratio 0.3. Temple/eye length ratio (dorsal view) 0.6. Antenna with 24 flagellomeres, first flagellomere about 4.0 times longer than wide, as long as second one.

Mesosoma: 2.0 times longer than wide (Fig. 22), 2.1 times longer than high (Fig. 23). Pronotal groove wide, deep and scrobiculate, pronotal carina distinct. Propleuron smooth. Mesoscutum slightly transverse, 0.7 times as long as wide. Mesoscutal lobes smooth, notauli deep and scrobiculate, obscured in an irregularly rugose median area before reaching the scuto-scutellar suture. Prescutellar sulcus with three distinct carinae. Scutellar disc smooth and triangular. Mesopleuron smooth. Precoxal sulcus deep and scrobiculate, running along basal two-thirds of mesopleuron. Subalar sulcus deep and rugose. Metanotum with a distinct median carina-like projection. Metapleuron entirely areolate-rugose. Propodeum with two divergent carinae running from median anterior edge delimiting two smooth dorsolateral areas; area beyond these carinae almost uniformly areolate-rugose.

Wings: fore wing (Fig. 28) length 3.0 mm, length/width ratio 3.85; vein 1cu-a postfurcal to vein 1M; veins 2RS/2M ratio 0.5.

Legs: fore tibia with a row of spines. Hind coxa transversally striate dorsally, smooth ventrally, with a distinct basoventral tubercule.

Metasoma: Basal sternal plate/length of first tergum 0.6. First metasomal tergite 2.2 times longer than apically wide (Fig. 29). Second median tergite longitudinally costate on basal three fourths, smooth apically. Suture between second and third median tergites slightly sinuate. Remaining tergites smooth and polished. Ovipositor length 1.4 mm, 0.9 times as long as metasoma.

Variation.

Body length 2.6-3.8 mm. Temple/eye length ratio in dorsal view 0.16-0.33. Antenna with 22-27 flagellomeres, white subapical band composed of two to four flagellomeres. In smaller specimens, rugose median area of mesoscutum reduced, though notauli never clearly distinguishable at posterior edge of mesoscutum, obscured among rugosities. Prescutellar sulcus sometimes with para-median carinae reduced, thus only the median carina is clearly distinguishable. Fore wing length 2.2-2.9 mm, length/width ratio 2.9-3.9 times its maximum width. Veins 2RS/2M ratio 0.5-0.55. Basal sternal plate 0.53-0.68 times length of first metasomal tergum. Ovipositor length 2.0-2.1 mm.

Males.

Body length 2.5-3.5 mm. Malar space 0.28. Temple/eye length ratio (dorsal view) 0.29-0.39. Flagellomeres 21-26 either entirely brown (Chiapas) (Fig. 27) or with two apical flagellomeres whitish (Oaxaca) (Fig. 25). Median apex of mesoscutum slightly coriaceous. Venter of mesosoma coriaceous to slightly coriaceous. Metapleuron coriaceous, coriaceous to slightly rugose distally. Fore wing 1cu-a vein slightly postfurcal to vein1M.2RS/2Mratio 0.47-0.51. Basal sternal plate 0.54 times length of first metasomal tergite.

Distribution.

This species is known from cloud forests located in the Reserva el Triunfo, Chiapas, and Santiago Comaltepec, Oaxaca, in southeast Mexico.

Biology.

Unknown.

Comments.

This species has a considerable variation in the antennal color pattern. We had originally grouped the specimens assigned to this taxon in two morphospecies, each represented by the specimens from Chiapas and Oaxaca, respectively. Females from Oaxaca have a distinct apical white band composed of 6-8 flagellomeres (Fig. 24), whereas in males this apical band is smaller (Fig. 25). On the other hand, most females from Chiapas have a white antennal band that is subapical and is only composed of 2-4 flagellomeres (Fig. 26). However, one female that could not be sequenced has an apical band similar to the specimens from Oaxaca. Other external morphological features (e.g. sculpture of propodeum and first metasomal tergite) also varied but we could not find any correlation with the geographical provenance of the specimens.

There was no concordance between the corrected COI distances and the geographic provenance and morphological variation for the above specimens. Some of the specimens from Oaxaca had lower COI distances with those from Chiapas than with the remaining specimens from the same locality (0.38-0.76 and 1.7-1.9%, respectively). This incongruence suggests that the existence of incomplete lineage sorting or hybridization between two recently diverged, sympatric species (see below). We have followed a conservative approach and consider the members of the populations from Chiapas and Oaxaca as a single species. One of the specimens from Oaxaca (DNA voucher number CNIN573) has considerably higher COI distances compared with the remaining conspecific specimens (3.6-4.7%). However, it is morphologically undistinguishable and we thus placed it within Sergey tzeltal .

Etymology.

The name of this species refers to the Tzeltal ethnic group, descendant from the Mayans that inhabits Los Altos, a mountain region located in central Chiapas

Material examined.

Holotype (CNIN): female, Mexico, Chiapas, Mpo. Albino Corzo, Reserva el Triunfo, 15° 39.428N, 92° 48.67W, YPT, 16/XI/2001, Kovarik col., DNA voucher number CNIN-711, GenBank accession numbers KC821997 (COI), KC822257 (cyt b), KC822078 (EF-1alpha; not included in this work), KC822122 (wingless; not included in this work). Paratypes (CNIN, MACN): one female, five males, same data as holotype, DNA voucher numbers CNIN712-15, 18, GenBank accession numbers KX074181-84, 87 (COI), KX074190-93 (cyt b), KX074195-97, 200 (28S); two females, same data as holotype except 15° 39.447N, 92° 48.40W, 17-20/XI/2001, DNA voucher numbers CNIN720-21, GenBank accession numbers KX074188-89 (COI); two females, five males, Mexico, Oaxaca, Mpio. Santiago Comaltepec, 17.62836 -96.4672; 6-8/VI/2009, YPT, 1495m, A. Zaldívar, H.Clebsch, DNA voucher numbers CNIN457-59, 461-64, GenBank accession numbers JN870332-34, 36-39 (COI), JN870515, 17-19 (cyt b), JN870673-74, 76-79 (wingless; not included in this work); one female, four males, Mexico, Oaxaca, Mpio. Santiago Comaltepec, 17.59056 -96.39902; 8/VI/2009, bosque mesófilo, 1998-2141m, A. Zaldívar, H.Clebsch, DNA voucher numbers CNIN468-71, GenBank accession numbers JN870343-46 (COI), JN870524 (cyt b), JN870681-84 (wingless; not included in this work); one male, Mexico, Oaxaca, Mpio. Santiago Comaltepec, La Esperanza, 17.62661 -96.36950; 8/VI/2009, cloud forest, 1600m, A. López, DNA voucher number CNIN479, GenBank accession number JN870352 (COI), KX074194 (cyt b), JN870689 (wingless; not included in this work); two females, five males, Mexico, Oaxaca, Mpio. Santiago Comaltepec, 17.62334 -96.34669; 6/V/2009, bosque mesófilo, 1460m, A. Zaldívar, DNA voucher numbers CNIN379-80, 446-48, 452-53, GenBank accession number JN870324-26, 295-96 (COI), JN870509-11, 466 (cyt b), JN870630-31, 64-65 (wingless; not included in this work), KC822056-57 (EF-1alpha; not included in this work).