Gymnocheta lucida Zimin, 1958

Pohjoismaeki, Jaakko & Bergstroem, Christer, 2021, Review of the Nordic Gymnocheta Robineau-Desvoidy (Diptera, Tachinidae) with report of two species new to Europe, ZooKeys 1053, pp. 145-184 : 145

publication ID

https://dx.doi.org/10.3897/zookeys.1053.52761

publication LSID

lsid:zoobank.org:pub:BA47DBD9-7A10-47D1-9036-E603CDDCF6C6

persistent identifier

https://treatment.plazi.org/id/6F759372-8A63-5C27-AB09-248252BE1220

treatment provided by

ZooKeys by Pensoft

scientific name

Gymnocheta lucida Zimin
status

 

Gymnocheta lucida Zimin

Gymnocheta lucida Zimin, 1958: 60. Lectotype ♂ [ZIN], by designation of Richter (1981: 917) (see below).

Material.

Russia: Lectotype ♂, by designation of Richter (1981: 917). Label: Майхэ близ Шкотова, Уссур. кр., 5.VI.1927, Штакельберг ( Mayhe near Shkotov , Ussur. kr., 5.VI.1927, Stackelberg ) - [Russia, Primorsky Krai, Ussuri district] [ZIN]. Examined from high quality photographs. Japan: (2♂♂, 1♀) 1♂: Honshu / 3. V. 1967 / H. Kurahashi // Gymnochaeta / lucida Mesn. (handwritten) / det. H. Shima, 1982 [BLKU]; 1♀: Honshu / 3. V. 1967 / H. Kurahashi [BLKU]; 1♂: [Aomori, Japan] / Inekari River , Koguriyama , / Hirosaki City / May 28, 2013 / D. Katô leg. // Gymnocheta / viridis Fall.? (handwritten) / det. T. Tachi 2020 [BLKU]. Finland: (5♂♂, 5♀♀) 1♂: Finland , Tavastia australis, Tammela , Torronsuo , 60.74, 23.58, 13.vi.2004, K. Mattila leg. (BOLD Sample-ID JP00605, GenBank accession number KX843924 View Materials ) [TMNH]; 1♂: Finland , Karelia borealis, Ilomantsi , Pirhunvaara , 62.973; 31.406, 24.vi.2008, J. Kahanpää leg. (BOLD Sample-ID jka08-00018, GenBank accession number KX844119 View Materials ); 1♂: Finland, Ostrobottnia borealis borealis, Rovaniemi, Kivalo, 66.325; 26.854, 13.-25.vi.2014, I. Gonzales leg. [JPC]; 1♀: Finland, Lapponia Kemensis pars occidentalis, Kittilä, Vuotsonperän jänkä, 67.617; 25.45, 24.vii.2007, J. Salmela leg. (BOLD Sample-ID JP00603, GenBank accession number KX843771 View Materials ) [TMNH]; 1♀: Finland, Tavastia australis, Juupajoki, Lakkasuo, 61.798; 24.317, 12.vii.2007, J. Pohjoismäki leg. (BOLD Sample-ID JP00604, GenBank accession number KX843828 View Materials ) [TMNH]; 1♂: Finland, Karelia borealis, Lieksa, Lahnasuo, 63.118; 30.6144, 20.v.-11.vi.2015, J. Pohjoismäki leg. (BOLD Sample-ID JP2019005) [JPC]; 1♂: ibid. Dissected. [JPC]; 2♀♀: Finland, Karelia borealis, Lieksa, Lahnasuo, 63.118; 30.6144, 12.vi.-3.vii.2015, J. Pohjoismäki leg. [JPC]; 1♀: Finland, Karelia borealis, Polvijärvi, Tiaissuo, 62.950233; 29.424098, 7.-27.vii.2014, J. Pohjoismäki leg. [JPC]. For the boundaries of the Finnish geographical provinces see https://laji.fi/theme/emk). Sweden: (64♂♂, 33♀♀) 1♀: Lu. Lpm, Jokkmokk, Kallkällmyran, O1677655 N7384113, 18.vi.1978, leg. R.&T-B. Engelmark [REC]; 1♀: Lu. Lpm, Jokkmokk, Kallkällmyran, O1677655 N7384113, 22.vi.1978, leg. R.&T-B. Engelmark [REC]; 1♀: Lu. Lpm, Jokkmokk, Kallkällmyran, O1677655 N7384113, 27.vi.1978, leg. R.&T-B. Engelmark [REC]; 1♀: Lu. Lpm, Jokkmokk, Kallkällmyran, O1677655 N7384113, 02.vii.1978, leg. R.&T-B. Engelmark [REC]; 1♂: Lu. Lpm, Jokkmokk, Kallkällmyran, O1677655 N7384113, 06.vii.1978, leg. R.&T-B. Engelmark [REC]- 1♀: Lu. Lpm, Jokkmokk, Kallkällmyran, O1677655 N7384113, 02.vii.1979, leg. R.&T-B. Engelmark [REC]; 1♂: Lu. Lpm, Jokkmokk, Kallkällmyran, O1677655 N7384113, 01.vi.1981, leg. R.&T-B. Engelmark [REC]; 1♀: Lu. Lpm, Jokkmokk, Keutatjape, O1667053 N7383578, 18.vi.1981, leg. R.&T-B. Engelmark [REC]; 1♂: Lu. Lpm, Jokkmokk, Kallkällmyran, O1677655 N7384113, 29.vi.1981, leg. R.&T-B. Engelmark [REC]; 1♂: Lu. Lpm, Jokkmokk, Kallkällmyran, O1677655 N7384113, 30.vi.1981, leg. R.&T-B. Engelmark [REC] Dissected.; 1♂: Lu. Lpm, Jokkmokk, Sasnekape, O1677032 N7380533, 13.vii.1981, leg. R.&T-B. Engelmark [REC]; 1♀: Lu. Lpm, Jokkmokk, Vaimat, ”Stormyren”, O1664900 N7384200, 16.vii.2008, leg. C. Bergström [CBC]; 1♀: Hls, Nordanstig, Ilsbo, Sörängsberget, O1564037 N6863588, 17.vii.1987, leg. C. Bergström [CBC]; 1♀: SE, Vrm, Kristinehamn, Flymossen, O1404043 N6580966, 14.vii.1985, leg. C. Bergström [CBC]; 4♂♂: SE, UP, Huddunge sn. Evighetsmossen, O1572552 N6657235, 30.v.1999, leg. C. Bergström [CBC], 1♂ dissected; 2♂♂: SE, UP, Huddunge sn. Evighetsmossen, O1572552 N6657235, 03.vi.1999, leg. C. Bergström [CBC]; 2♀♀: SE, UP, Huddunge sn. Evighetsmossen, O1572550 N6657230, 16.vi.2003, leg. C. Bergström [CBC] Dissected; 1♂: 30 / 220 // SE, UP, Huddunge sn. Evighetsmossen, O1572552 N6657235, 29.v.2020, leg. C. Bergström [CBC]; 2♂♂: 61-62 / 2020 // SE, UP, Huddunge sn. Evighetsmossen, O1572552 N6657235, 04.vi.2020, leg. C. Bergström [NHRS]; 2♂♂: 70-71 / 2020// SE, UP, Huddunge sn. Evighetsmossen, O1572552 N6657235, 05.vi.2020, leg. C. Bergström [CBC]; 3♂♂, 2♀♀: 72-76 / 2020 // SE, UP, Huddunge sn. Öjemossarna, O1571242 N6657364, 09.vi.2020, leg. C. Bergström [CBC]; 1♂: 82 / 2020 // SE, UP, Huddunge sn. Öjemossarna, O1571242 N6657364, 10.vi.2020, leg. C. Bergström [BLKU]; 1♂: 83-92 / 2020 // SE, UP, Huddunge sn. Öjemossarna, O1571242 N6657364, 10.vi.2020, leg. C. Bergström [CBC]; 6♂♂: 111-116 / 2020 // SE, UP, Huddunge sn. Evighetsmossen, O1572270 N6657616, 15.vi.2020, leg. C. Bergström [CBC]; 15♂♂: 117-131 / 2020 // SE, UP, Järlåsa sn. Ramsmossen, O1574877 N6649254, 18.vi.2020, leg. C. Bergström [CBC]; 2♀♀: 138-139 / 2020 // SE, UP, Huddunge sn. Evighetsmossen, O1572270 N6657616, 21.vi.2020, leg. C. Bergström [CBC]; 1♀: 141-142 / 2020 // SE, UP, Huddunge sn. Evighetsmossen, O1572270 N6657616, 21.vi.2020, leg. C. Bergström [BLKU]; 2♀♀: 141-142 / 2020 // SE, UP, Huddunge sn. Evighetsmossen, O1572270 N6657616, 21.vi.2020, leg. C. Bergström [NHRS]; 1♂ ♀: in copula, 9♂♂: 144-145, 154-162 / 2020 // SE, UP, Huddunge sn. Evighetsmossen, O1572552 N6657235, 21.vi.2020, leg. C. Bergström [CBC]; 1♂ ♀: in copula, 2♂♂, 10♀♀: 183, 165-175,184-185 / 2020 // SE, UP, Huddunge sn. Evighetsmossen, O1572552 N6657235, 23.vi.2020, leg. C. Bergström [CBC]; 1♂, 2♀♀: 194-195, 200 / 2020 // SE, UP, Huddunge sn. Evighetsmossen, O1572552 N6657235, 29.vi.2020, leg. C. Bergström [CBC] GoogleMaps

Diagnosis.

Gymnocheta lucida Zimin is a dark metallic olive to bronze-green tachinid, often with a matt appearance due to a dense microtomentum, which also gives the genal dilation a greyish white appearance.

Redescription.

Body length: 7.2-9.5 mm (n = 29).

Male (Figs 2A View Figure 2 , 4A View Figure 4 , Ei, 5A:i, B:i, C:i).

Colouration: Head covered with dense greyish white microtomentum. The metallic ground colour of the genal dilation shines through weakly, compared to G. magna and G. viridis . However, this difference is sometimes hard to recognise, as the interpretation depends on the direction of the incidence of light, and the specimens should be viewed from different angles. Facial plate black normally without a metallic green spot. Occiput, postgena, genal dilation dark metallic bronze-green in ground colour, frontal plate sometimes narrowly metallic bronze-green along the frontal setae, ocellar triangle mostly black. Palpus deeply black (charcoal) or dark brown in older bleached specimens. Prementum black, labella brown. Thorax and abdomen metallic dark olive green in ground colour, shine depending on the direction of the incidence of light; covered with greyish white microtomentum. The intensity of the microtomentum varies, some specimens having more matt appearance than others and in general the microtomentum in males is more dominant than in females. The intensity of the green colouration is variable, some specimens are more lucid green while others, especially from cooler locations, are very dark, almost blackish green. Scutum, when viewed from the side and slightly from behind, with four longitudinal stripes of microtomentum, changing from grey to purple depending on the direction of the incident light. In aged specimens, caught late in the season, the microtomentum can be worn out and give the specimens a polished appearance for the most dorsal part of scutum and postpronotum. Proepisternum black and densely covered with microtomentum. Fore coxa in anterodorsal region and sometimes also femora with remnants of metallic shine, covered with light grey microtomentum. Wing membrane around crossvein r-m narrowly (sometimes somewhat indistinctly) infuscate. Tegula and basicosta black.

Head (Fig. 2A View Figure 2 ): Frons at its narrowest point, 0.43-0.51 (n = 19) × as wide as an eye in dorsal view. Frontal vitta tapering toward middle (sometimes narrowest at this point) and then parallel-sided towards the ocellar tubercle. Head in profile somewhat protruding at level of antennal insertion, width of parafacial at this level ca. 0.55-0.65 × (n = 17) the horizontal eye diameter. Fronto-orbital plate with a row of 10-12 medioclinate moderately strong frontal setae and some additional setulae, uppermost setula tiny sometimes slightly reclinate, four or five setae descending on upper part of parafacial, reaching the middle of the pedicel with the row curving laterally, and here sometimes attended by some setulae; fronto-orbital plate outside the frontal row of setae with sparsely, spread, short and tiny setulae. Height of face slightly shorter than the length of frons (n = 17). Gena in profile at narrowest point, 0.29-0.38 (n = 14) × as high as vertical eye diameter. Vibrissa normally well-developed but in some specimens there is no distinct vibrissa but two or three equally strong supravibrissal setae. Facial plate slightly convex but hardly visible in profile, but lower facial margin protruding especially in the middle but in profile hardly below the subvibrissal setae. Facial ridge on less than lower 1/5 with 2-4 strong and 0-2 additional thinner supravibrissal setae (length of them at least equals narrowest width of parafacial) and 2-4 thin and short setulae. Ridge below vibrissa with 3-5 strong subvibrissal setae continuous with the genal setae, longest ca. 0.5 × the length of vibrissa. Inner vertical setae strong and crossed, longer than the ocellar setae, outer vertical setae less developed, subequal with the adjacent postocular setae. Postocular setae long and thin, apically pronouncedly bending forward over the eyes. Occiput with a pair of postocellar setae mostly subequal with the outer vertical setae, but sometimes missing. Palpus slightly clavate at tip, subequal to the length of the antenna and densely covered with short black setulae 2 strong preapical setulae and four or five irregular ventral setulae. Antenna: First flagellomere in profile 1.10-1.32 ×) (n = 15) wider than parafacial at narrowest point, and 1.39-1.56 (n = 15) × as long as pedicel. Arista widened in at least its basal 1/2 (sometimes almost in basal 2/3) and gradually tapering to apex.

Thorax: Prosternum bare. Scutum with 3(2)+3 acrostichal, 3(2)+4 dorsocentral and 1+3 intra-alar setae. Ground vestiture on scutum (consisting of thin setulae) dense and erect, longest setulae subequal to the shortest setae. Scutellum normally with four (rarely five) pairs of strong marginal setae, the subapical pair sometimes inserted close to apex, a tiny pre-basal seta present at least on one side; normally four suberect preapical discal setae, forming a row in front of the marginal setae, the strongest pair in the middle sometimes subequal to the lateral setae, mixed with numerous tiny setulae the longest at least 1/5 as long as the strong preapical setae.

Legs: Claws and pulvilli on fore legs ca. 1.1-1.2 (n = 5) × as long as tarsal segment 5, the latter 2.0-2.1 (n = 5) × as long as tarsal segment 4. Fore tibia with a row of 4-6 anterodorsal setae and two or three thin setulae, 4-7 setae/setulae in an irregularly posterior or posterodorsal position (often two or three of them representing setae but sometimes only five tiny setulae present): preapical anterodorsal seta well developed, subequal with the preapical dorsal and preapical posterior setae. Mid tibia with a row of 4-6 anterodorsal setae the strongest in the middle, 2-4 posterodorsal setae (at least two are strong), two posterior setae, one ventral seta often accompanied by a tiny setula. Hind tibia with equally long preapical anterodorsal and posterodorsal setae, apical posteroventral seta ca. 1/2 length of the anterioventral seta; a continuous irregular row of 8-11 anterodorsal setae / setulae of which 4-6 represent strong setae, three or four posterodorsal setae and two or three anteroventral setae.

Wing: Usually two costal spines (rarely one or three), the strongest lower spine ca. 3 × as long as the surrounding costal setulae, normally only somewhat shorter than crossvein r-m. Fourth and fifth costal section 1.8-2.1 (n = 6) × as long as sixth costal sector. Vein R4+5 with 3-7 ventral and 2-9 dorsal setulae (in one deviating specimen with nine setulae almost reaching r-m). Cell r4+5 often somewhat narrowly open at wing edge, 0.50-0.75 × the length of crossvein r-m.

Abdomen (Fig. 4A View Figure 4 ): Domed, ground-vestiture erect or at least semierect on tergites 3 and 4, also ventrally. Tergite 2 with two (rarely one) lateral setae on each side. Tergite 3 with two or three pairs of unequally often irregularly set strong median discal setae, with a pair of median marginal setae and 2(3) lateral setae on each side. Tergite 4 with two or three pairs of unequally and likewise irregularly set strong median discal setae, in dorsal view with a full row of 10-12 marginal setae. Tergites 3 and 4 frequently with one median discal seta missing or set more laterally. Tergite 5 with two or three irregular rows of unequally strong discal setae and a row of medium strong marginal setae.

Terminalia (4 dissections) (Figs 4A View Figure 4 , Ei, 5A:i, B:i, C:i): Sternite 5 (Fig. 4A View Figure 4 , Ei) in ventral view with finger-like lobes; length of cleft (measured from the anteriormost indentation) 2.5 × its width. Lobes with widespread setulae, rounded at apex. Dorsomedial process narrow and somewhat indistinct. Basal plate bare (without setulae) ca. 0.4 × as long as sternite 5 and 2.2-2.3 × as wide as long. Syncercus in profile (Fig. 5A View Figure 5 :i) smoothly curved before apex, in caudal view (Fig. 5B View Figure 5 :i) rounded at apex; 2 × as long as its maximal width (measured from base of membranous median suture to apex); vaguely curved inwards at middle and close to apex; numerous dorsolateral setulae at middle gives a characteristic dense and fur-like appearance. Surstylus (Fig. 5A View Figure 5 :i) bacilliform with some tiny setulae most prominent along posterior margin in the proximal region, otherwise with numerous spread sensory pores, straight in caudal view, in profile gradually tapering at base, smoothly curved, evenly thick apart from an indicated widening at apex, bent towards syncercus. Pregonite lance-like in caudal view; lobe-like in profile (Fig. 5C View Figure 5 :i) with a narrow hook-like projection apically, shortly tapering at apex, with short sensorial hairs along its posterior margin, anterior margin to some extent incurved. Aedeagus: distiphallus in profile compact and widest close to apex (Fig. 5C View Figure 5 :i).

Female (Figs 3A View Figure 3 , 6A View Figure 6 :i, B:i): Differs from male as follows:

Colouration: Fronto-orbital plate almost entirely metallic bronze-green when viewed from behind and slightly from above; the metallic ground colour at least partly interrupted on the upper part of parafacial, sometimes in patches reaching the level of the lowermost frontal setae. However, most of the metallic ground colour on upper part of parafacial and anterior 1/3 of fronto-orbital plate is covered by greyish white microtomentum, dense especially along eye margin and frontal setae, but when viewed from side and slightly from above with golden reflections. Thorax and abdomen dark metallic green to bronze-green, microtomentum normally thinner than in males, most intense on the pleura and episternum.

Head (Fig. 3A View Figure 3 ): Frons wider, at its narrowest point 0.78-0.93 (n = 10) × as wide as an eye in dorsal view. Frontal vitta tapering toward middle (sometimes narrowest at this point) and then gradually widening towards the ocellar tubercle, its width at ocellar tubercle exceeding the width of fronto-orbital plate at this point. Fronto-orbital plate normally with fewer, 7-11 moderately strong medioclinate frontal setae. Outer vertical setae strong 0.65-0.75 × the length of inner vertical setae; subequal with the ocellar setae and the posterior proclinate orbital setae, distinctly stronger than the lateroclinate orbital setae and at least twice the length of the adjacent postocular setae. Postocellar setae short, tiny and subequal with the upper postocular setae. First flagellomere 1.29-1.46 (n = 10) × as long as pedicel, normally ca. as wide as parafacial at narrowest point.

Legs: Claws and pulvilli on fore legs shorter, ca. 0.7-0.8 (n = 5) × as long as tarsal segment 5, the latter 1.5-1.6 (n = 5) × as long as tarsal segment 4.

Abdomen: Ground vestiture dorsolateral on tergites 3 and 4 distinctly prone contrasting to the erected setulae between the median discal setae. Tergites 3 and 4 with two or three pairs of median discal setae. Sternite 5 somewhat elongated, 1.1-1.2 × as long as its maximal width (Fig. 6A View Figure 6 :i), with 5-8 strong setae in posterior 1/2, three or four of them along the posterior margin, in posterior 2/3 accompanied by numerous (50-60) irregularly spread setulae of varying size.

Terminalia (2 dissections) (Fig. 6A View Figure 6 :i, B:i): Tergite 6 divided into narrow and somewhat elongated hemitergites, widely separated, each closely accompanied by 0-3 tiny setulae in the posterior membranous area (and sometimes indicated by a pair of setulae in a more apical position). Sternite 6 shorter 0.6-0.7 × as long as but slightly wider (1.2 ×) than sternite 5, 1.5-1.6 × as wide as long with 8 setae (n = 3) along the posterior margin and with numerous tiny setulae in posterior 1/5. Tergite 7 with 0-3 setulae in the adjacent membranous area. Sternite 8 with 6-8 sensory pores (sensilla trichodea). Hypoproct (Fig. 6B View Figure 6 :i) in ventral view almost triangular, apex only slightly rounded (studied in ventral and somewhat caudal position pointed at apex): with a quite poorly developed medioventral depression, densely covered with setulae that laterally are longer; in profile slightly bent towards the cerci, apex of hypoproct hardly reaching tip of cerci, lingulae well developed. Epiproct in caudal view indicated by the presence of three or four setulae inserted above the cerci. Cerci short with numerous setulae of varying length, the strongest setulae in profile subequal to the length of sternite 7.

DNA.

The Co1 DNA barcode sequence of G. lucida differs markedly from the other European species of Gymnocheta (Fig. 7 View Figure 7 ). It has been assigned a species-specific Barcode Index Number (BIN): BOLD:ACF3891.

Distribution.

Gymnocheta lucida was previously known only from the Russian Far East and Japan ( Richter 2004) and we report it here for the first time as also common and widespread in Finland and northern Sweden. In the Barcode of Life Database (BOLD), there is one match for the species-specific BIN from Norway. This species likely occurs also elsewhere in Europe but has been confused with the common G. viridis , and may have a continuous range throughout the Central Palaearctic.

Biology.

Almost all Finnish records of G. lucida are from ombrotrophic raised bogs. The only exception is the record from Rovaniemi, Lapland (Finland), collected from a pine forest habitat. However, it is typical that insect species that are specific to bogs or moorlands in the south extend their habitat preferences to open forests or heathlands in the north. Gymnocheta viridis is also sometimes recorded from bogs, so the habitat is not a reliable indicator for the species. Similarly, the habitats in Uppland are best described as ombrotrophic bogs separated by different types of coniferous woodlands. The bogs partly covered with dwarfed pine trees, and a scrub layer dominated by Vaccinium uliginosum , Rhododendron tomentosum , Myrica gale , Calluna vulgaris , and Betula nana . The coniferous area surrounding the bogs consists discontinuously of rocky outcrops densely covered by different lichens, i.e., Cladonia sp. and Cetraria islandica , and old pine trees, and sinks also with old pine trees and single spruces; the scrub layer here is dominated by Vaccinium myrtillus but also with elements of Vaccinium vitis-idaea , Rhododendron tomentosum , and Vaccinium uliginosum . The three collection sites of Kallkällmyran, Keutatjape, and Sasnnekape are located just south of the Arctic Circle in Jokkmokk, Lule Lappmark (Sweden). They have been described as rich to medium rich fens in the coniferous zone near Jokkmokk ( Engelmark and Engelmark 1989). These minerotrophic fens are fed with ferriferous groundwater and the complex vegetation is characterised by Saxifraga hirculus .

Males appear in late May and individuals are first and foremost observed in small sunlit clearings in the sinks between the rocky outcrops, sitting on leaves and twigs of blueberries apparently watching for approaching females. Some of these clearings likely represent hot spots for aggregation. These are frequently attended by males that fly out sporadically from time to time in response to another passing male, but in one of these hot spots mating was observed on two occasions. One male was collected when visiting the flowers of Rhododendron tomentosum . Females appear around second week of June and they are, apart from the ones observed in copula, found on the edge of the bogs close to the rocky outcrops. They have been observed between late June to mid-July in characteristic slow, searching flight, low in the vegetation often just a couple of inches above the moss layer, examining tufts of sedges and shrubs, such as Vaccinium uliginosum and Betula nana . The hosts are currently unknown but concealed larvae of Noctuidae or Erebiidae ( Lepidoptera ), living in the habitats described above, are most likely.

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Diptera

Family

Tachinidae

Genus

Gymnocheta

Loc

Gymnocheta lucida Zimin

Pohjoismaeki, Jaakko & Bergstroem, Christer 2021
2021
Loc

Gymnocheta lucida

Zimin 1958
1958