Euthycerina vittithorax Malloch, 1933

Mortelmans, Jonas & Hendrix, Jef, 2020, Review of Euthycerina Malloch (Diptera, Sciomyzidae), with description of a new species from Chile, Zootaxa 4786 (3), pp. 381-395 : 391-392

Euthycerina vittithorax Malloch

( Figs 3c , 4c , 5c , 6 e–h, 7c, 8c)

In total, one holotype, one allotype, and 26 paratypes were mentioned in Malloch (1933), of which we were able to recover the holotype, the allotype, and 20 paratypes. The Bristish History Museum (BHM, now NHMUK) expedition of 1926 yielded another four specimens of E. vittithorax , from Tierra del Fuego and Lake Gutiérrez. These specimens were not listed as types by Malloch (1933), and they do not bear type labels.

Allotype studied NHMUK010862554 . Adult ♀. The female allotype is a bit dusty but otherwise is in perfect condition. The allotype is preserved dry, pinned on a micropin. The original labels from top to bottom: “Type [round white label with red margin, black printed text]”, “Bariloche, 7 XI 1926 ”, “ Argentina, Terr. Rio Negro, F. & M. Edwards. B.M. 1927-63 ”, “ NHMUK 010862554 ”.

Paratypes studied NHMUK010862555 . Adult ♂. The male paratype is in relatively bad condition: both wings and left hind leg are missing; the abdomen has been dissected and is stored in a microvial on the same pin as the remainder of the specimen. The paratype is preserved dry, pinned on a micropin. The original labels from top to bottom: “ Paratype [round white label with yellow margin, black printed text]”,”Ancud, 17-19 XII 1926 ”, “ Chile, Chiloe I., F. & M. Edwards. B.M. 1927-63 ”, “ NHMUK 010862555 ” .

NHMUK010862556 . Adult ♂. The male paratype is in good condition, preserved dry, mounted on a mi- cropin. The original labels from top to bottom: “ Paratype [round white label with yellow margin, black printed text]”,” Euthycerina vittithorax Mall. ”, “Record in exchange, ex. coll. BM ”, ”Puntra, 19 XII 1926 ”, “S. Chile, Chiloe I., F. & M. Edwards. B.M. 1927-63 ”, “ NHMUK 010862556 ” .

Other specimens studied 1♂. “ L. Gutiérrez, 3-14 XI 1926 ’,’ Argentina: Terr. Rio Negro, F. & M. Edwards. B.M. 1927-63 ”, “ NHMUK 010862600 ”. ”det. Mortelmans, Euthycerina vittithorax Malloch ”. NHMUK .

1♂ “ Tierra del Fuego, Rio Grande , 28XI1931. P.W. Reynolds, BM 1932-311 ”,” NHMUK 010862599 ”,”det. Mortelmans, Euthycerina vittithorax Malloch ”. In NHMUK .

1♀ “ Nothofagus forest ”, “ Chile, Puerto Williams, HW3, Isla Navarino. 55°S, 1200ft, 14I1959 ”,” Euthycerina vittithorax Malloch , det. J.C. Deeming 1965”, ” NHMUK010862596 ”. NHMUK .

1♀ “ Nothofagus forest ”, ” Chile, HE17, Puerto Eden, Isla Wellington, 49°S, 25ft, 6 XII 1958 ”, “Royal Soci- ety Chilean Expedition 1959”, “ Euthycerina vittithorax Malloch , det. J.C. Deeming 1965”,” NHMUK010862597 ”. NHMUK .

1♀ “ Sedge and Heath ”, ” Chile, HE16, Puerto Eden, Isla Wellington, 49°S, 60ft, 6 XII 1958 ”, “Royal Society Chilean Expedition 1959”, ”,” Euthycerina vittithorax Malloch , det. J.C. Deeming 1965”,” NHMUK010862598 ”. NHMUK

1♂ 4♀, “ Chile: Magallanes: 12km S of Punta Arenas. 1 XII 1966, C.O.Berg ”, “det. Mortelmans, Euthycerina vittithorax Malloch ”. CUIC [specimens from series Euthycerina parvula ]

9♂ 7♀, “ Chile: Magallanes: 12km S of Punta Arenas. 2 XII 1966, C.O.Berg ”, “ J66120 ”, “det. Mortelmans, Euthycerina vittithorax Malloch ”. CUIC [specimens from series Euthycerina parvula ]

2♀, “ Chile, Santiago, los maitenes, 12 X 1966 C.O. Berg ”, ”det. Mortelmans, Euthycerina vittithorax Malloch ”. CUIC [specimens from series Euthycerina parvula ]

1♂, 1♀, “ Argentina, SW of Punta de Arénas , 27 XI1966, C. O. Berg ”, ”det. Mortelmans, Euthycerina vittithorax Malloch ”. CUIC [specimens from series Euthycerina parvula ]

1♀, Argentina, San Marha , 6 XII 1967. In NHMUK

1♂. Collected in malaise trap ( MT), dried, and mounted to pin. The original labels from top to bottom: “13218 (sample cd), (Ch): Region IX Araucanía, prov. Cautín, SE of Curacautín, Parque Nacional Conguillío, sector Captrén, trail Los Carpinteros, site Conguillío MT & PT03 , 38°38’24.5S, 71°41’46.3W, 1264m, 9-21 I 2013, MT #1 ,, leg Marc Pollet & Anja De Braekeleer, sorted by M. Pollet 2013”, “ Euthycerina vittithorax det. Mortelmans ”. MNNC .

Other types, not studied Holotype 1♂, The original labels from top to bottom: “Type [round white label with red margin, black printed text]”, “ Euthycerina vittithorax Type, det. JR Malloch ”, “Bariloche, 25 X – 28 X 1926 ”, “ Argentina, Terr. Rio Negro, Edwards, F. & M. Edwards. B.M. 1927-63 ”. NHMUK.

Paratype 2♀, The original labels from top to bottom: “Type [round white label with yellow margin, black print- ed text]”, “ Euthycerina vittithorax Type, det. JR Malloch ”, “Casa Pangue, 4-10XII 1926 ”, ”S. Chile: Llanquihue prov. F. & M. Edwards. B.M. 1927-63 ”. NHMUK .

Paratypes: 1♂ 2♀, The original labels from top to bottom: “Type [round white label with yellow margin, black printed text]”, “ Euthycerina vittithorax Type, det. JR Malloch ”, “ L. Nahuel Huapi, Eastern End , 28-31 X 1926 ”, “ Argentina, Terr. Rio Negro., F. & M. Edwards. B.M. 1927-63 ”. NHMUK .

Paratype 2♀, The original labels from top to bottom: “Type [round white label with yellow margin, black printed text]”, “ Euthycerina vittithorax Type, det. JR Malloch ”, “ L. Correntoso, 18-25 XI 1926 ”, “ Argentina, Terr. Rio Negro., F. & M. Edwards. B.M. 1927-63 ”. NHMUK .

Paratype 1♀, The original labels from top to bottom: “Type [round white label with yellow margin, black print- ed text]”, “ Euthycerina vittithorax, Malloch ”, “Record in exchange, ex. coll. B.M”, “Puerto Sabino, 2 XII 1926 ”, “ Argentina, Terr. Rio Negro., F. & M. Edwards. B.M. 1927-63 ”. NHMUK .

Paratype 1♀, The original labels from top to bottom: “Type [round white label with yellow margin, black print- ed text]”, “ Euthycerina vittithorax, Malloch ”, “Record in exchange, ex. coll. B.M”, “Ensenada, 14-15 XII 1926 ”, “S. Chile: Llanquihue prov. , F. & M. Edwards. B.M. 1927-63 ”. NHMUK .

Adult 1♂. The original labels from top to bottom: “ Type [round white label with yellow margin, black printed text]”, “Bariloche, 3 XI 1926 ”, “ Argentina, Terr. Rio Negro, F. & M. Edwards. B.M. 1927-63 ”. NHMUK.

Adult 1♀. The original labels from top to bottom: “ Type [round white label with yellow margin, black printed text]”, “Bariloche, 25-28 X 1926 ”, “ Argentina, Terr. Rio Negro, F. & M. Edwards. B.M. 1927-63 ”. NHMUK.

Adult 2♂ 2♀. The original labels from top to bottom: “ Type [round white label with yellow margin, black printed text]”, “Bariloche, 28XI-1XII 1926 ”, “ Argentina, Terr. Rio Negro, F. & M. Edwards. B.M. 1927-63 ”. NHMUK.

Adult 1♂. The original labels from top to bottom: “ Type [round white label with yellow margin, black printed text]”, “Bariloche, 5-10 XI 1926 ”, “ Argentina, Terr. Rio Negro, F. & M. Edwards. B.M. 1927-63 ”. NHMUK.

Other specimens, not studied 2♀, The original labels from top to bottom: “ Euthycerina vittithorax , det. JR Malloch ”, “L Gutierrez, 3 -14 XI 1926 ”, “ Argentina, Terr. Rio Negro., F. & M. Edwards. B.M. 1927-63 ”. NHMUK .

A relatively large species, easily distinguished. General color bright, light brownish with scutum heavily infuscated, 5 to 7 strong longitudinal gray pubescent lines (broad AC, broad DC, and divided into two behind suture, very broad SA) ( Fig. 7c ). Frontal vitta wide, always connected to and as wide as occipital triangle ( Fig. 4c ). Cell r 1 with 2 to 3 large hyaline spots ( Fig. 3c ). In male, tergite 5 in lateral and ventral view characteristic and very different than that of congeners ( Fig. 6 e–h)

Euthycerina vittithorax is found throughout southern Chile and southern Argentina ( Fig. 1 ). In contrast to the situation with E. pilosa , we encountered only slight variation in characters of E. vittithorax . It is the most common species of Euthycerina .

The material preserved in the CNC yielded eight records of E. vittithorax from Chile (Osorno province). These specimens were identified as E. vittithorax by W.L. Murphy in 2014 (pers. comm.). The large series of specimens labelled Euthycerina “ parvula ” borrowed from the CUIC proved to be E. vittithorax ; as this series contained both male and female specimens, identification was confirmed on the basis of dissected male terminalia.

Figures

FIGURE 1. Map of southern Chile and Argentina, the distribution of the genus Euthycerina Malloch is plotted. Red square: specimens of E. pilosa; red triangle: type specimens of E. pilosa; green square: specimens of E. vittithorax; green triangle: type specimens of E. vittithorax; orange triangle: type specimens of E. uachi. Unidentified specimens of Euthycerina are not plotted. An interactive version of this map is found online (Mortelmans, 2019).

FIGURE 3. Wings of (A) the male holotype E. uachi, (B) the male paratype E. pilosa, and (C) the male paratype of E. vittithorax.

FIGURE 4. Head in dorsolateral view of (A) the male holotype of E. uachi, (B) a male specimen of E. pilosa, and (C) the male paratype of E. vittithorax. Because we had no type material of E. pilosa that included a head, a typical specimen was chosen for this photograph. In addition to the frontal vitta, note the arista, the back of the head, and the color of the scutum, all of which are diagnostic characters.

FIGURE 5. Habitus in lateral view of (A) the male holotype of E. uachi, (B) the male paratype of E. pilosa, and (C) the male paratype of E. vittithorax.

FIGURE 6. Male terminalia of (A–D) the male paratype of E. pilosa; (E–H) the male paratype of E. vittithorax; (I–L) the male holotype of E. uachi. Male terminalia, posterior view (A, E, I); male terminalia, lateral view (B, F, J); male tergite 5, lateral view (C, G, K); male tergite 5, ventral view (D, H, L). Each facet on a row is drawn on the same scale, and the corresponding scale bars indicate 0,5mm.

FIGURE 7. Dorsal view of the mesonotum of the male holotype of E. uachi (A), the male paratype of E. pilosa (B), and the male paratype of E. vittithorax (C). Scale bar same for all three specimens: 1mm.