Serichlamys vexilliphallus Reemer & Mengual, 2025

Reemer, Menno & Mengual, Ximo, 2025, Revision of the Neotropical species of the hoverfly genus Serichlamys Curran, 1925 (Diptera, Syrphidae, Microdontinae), ZooKeys 1243, pp. 51-106 : 51-106

Serichlamys vexilliphallus Reemer & Mengual sp. nov.

Figs 7 , 126–130 , 150–153

Type material.

Holotype. Ecuador • 1 ♂, holotype of Serichlamys vexilliphallus sp. nov.; Napo Prov., Huahua Sumaco, km 44 on Hollin-Loreto road ; 17 Dec. 1989; M. J. Wasbauer & H. Real leg.; CSCA.

Label 1: “ ECUADOR: Napo Prov. // Huahua Sumaco, km 44 // on Hollin-Loreto rd // XII- 17-1989 mal. trap // M. & J. Wasbauer, H. Real ”; label 2: “ Serichlamys sp. nov. // Det. M. Reemer 2022 /. / Specimen code MR 1480 ”. Paratypes. Ecuador • 1 ♂; Napo Prov., Huahua Sumaco, km 45 on Hollin-Loreto road ; 14 Dec. 1989; M. J. Wasbauer & H. Real leg.; CSCA • 2 ♂; Napo Prov., Huahua Sumaco, km 45 on Hollin-Loreto road ; 15 Dec. 1989; M. J. Wasbauer & H. Real leg.; CSCA • 2 ♂; Napo Prov., Huahua Sumaco, km 45 on Hollin-Loreto road ; 16 Dec. 1989; M. J. Wasbauer & H. Real leg.; CSCA • 1 ♂; Napo Prov., Huahua Sumaco, km 45 on Hollin-Loreto road ; 18 Dec. 1989; M. J. Wasbauer & H. Real leg.; RMNH [specimen code MR 1483 ] • 2 ♂; Napo Prov., Huahua Sumaco, km 45 on Hollin-Loreto road ; 20 Dec. 1989; M. J. Wasbauer & H. Real leg.; CSCA • 1 ♂; Napo Prov., Huahua Sumaco, km 45 on Hollin-Loreto road ; 21 Dec. 1989; M. J. Wasbauer & H. Real leg.; RMNH • 2 ♂; Morona Santiago: Miazal, 50 km SE Macas ; 300 m asl; 4–7 Jan. 1993; M. & J. Wasbauer leg.; CSCA • 5 ♂; Napo, Misahualli nr. Tena ; 3–8 Oct. 1999; S. R. Keller leg.; LACM • 1 ♂; Napo Prov., Jatun Sacha Biological Station ; 01°03'58.4"S, 77°37'0.6"W; 26 Aug. 2019; X. Mengual leg; ZFMK [ ZFMK -DIP-00068685 ]; GenBank accession no. PQ 629008 .

Additional specimens.

Panama • 1 ♂; Chiriqui province, 8 km S Boquete ; 08°41'54"N, 82°27'06"W; 800 m asl; 16–30 Jun. 2012; F. D. Parker & T. D. McIntyre leg.; CSCA . PERU • 1 ♂; Amazonas, Distr. Aguas Verdes, Bagua / Tarapoto Rd. (5 N) at km 403 ; 5°41'23"S, 77°38 13"W; 1125 m asl; 15–22 May 2009; M. E. Irwin & G. A. Amaya leg; CNC [J. Skevington molecular specimen # 9948] • 1 ♂; SAM: around San Roque de Cumbaza ; 6°23'4.96"S, 76°25'53"W; 15–31 Jan. 2015; T. Faasen leg; RMNH [M. Reemer specimen code MR 0565; also CNC 464838 ]; GenBank accession no. PQ 629015 • 1 ♀; Fundo Chela ; 4 Jun. 1964; 1100 m asl; J. Schunke leg.; NHMUK . Colombia • 1 ♂; Putumayo, Villa Garzon, 8 mi. S. Mocoa ; 3 Aug. 1978; M. Cooper leg.; NHMUK [ NHMUK 013624759 ] • 1 ♂; Putumayo, Villa Garzon ; 400 m asl; 30 Aug. 1984; M. Cooper leg.; NHMUK [ NHMUK 013624761 ] ; • 1 ♂; Putumayo, Villa Garzon ; 400 m asl; 7 Oct. 1984; M. Cooper leg.; NHMUK [ NHMUK 013624743 ] ; 1 ♂; Putumayo, Villa Garzon ; 400–600 m asl; 31 Dec. 1990; M. Cooper leg.; NHMUK [ NHMUK 013624760 ] • 1 ♂; Caqueta, Yuruyaco, 73 km SW Florencia ; 5 Feb. 1979; M. Cooper leg.; NHMUK [ NHMUK 013624748 ] . ECUADOR • 1 ♀; Morona-Santiago, Sucua [?]; 850 m asl; 15 Jul. 194; M. Cooper leg.; NHMUK [ NHMUK 013624762 ] • 1 ♂; Morona-Santiago, Cord de Cutucu, 6 km E. of Macas ; 1100 m asl.; 17 Mat 1987; M. Cooper leg.; NHMUK [ NHMUK 013624746 ] • 1 ♀; Morona-Santiago, Cord de Cutucu, 6 km E. of Macas ; 1100 m asl.; 17 Mat 1987; M. Cooper leg.; NHMUK [ NHMUK 013624745 ] • 1 ♂; Napo, Muyuna, 5 km W of Tena ; 500 m asl.; 13 Apr. 1981; leg. M. Cooper; NHMUK [ NHMUK 013624749 ] • 1 ♂; Napo, near Myuna ; [no date on label]; M. Cooper leg.; NHMUK [ NHMUK 013624832 ] .

Description

(based on holotype). Adult male Body size: 6.5 mm.

Head. Face occupying slightly <1 / 3 of head width in frontal view; shiny black with faint green hue; white setulose. Gena very narrow; black; white setulose. Oral margin laterally not produced. Frons black; medially bare, laterally with mixed white and black setulae. Vertex black; black setulose except yellowish setulose along anterior and posterior margins. Occiput black; dorsal 1 / 3 pale yellow setulose, otherwise white setulose. Eye bare. Antennal fossa slightly higher than wide. Antenna blackish brown; antennal ratio ~ 4: 1: 4.5.

Thorax. Scutum shiny black, with green sheen on median 1 / 3 and bronze sheen on lateral 1 / 3; black golden yellow setulose on anterior 1 / 4 and narrowly along lateral and posterior margins, otherwise black setulose. Postpronotum and postalar callus yellowish brown; yellow setulose. Scutellum trapezoid, with two calcars as long as ~ 1 / 4 of scutellar length; shiny dark brown with faint greenish sheen, except calcars yellow; yellow setulose. Pleura shiny dark to yellowish brown. Anepisternum with shallow sulcus; yellow setulose anterodorsally and posterodorsally, widely bare medially and ventrally. Anepimeron yellow setulose with a few black setulae dorsally. Katepisternum with patch of white setulae dorsally and small patch of white setulae ventrally. Katatergite long microtrichose, anatergite short microtrichose. Calypter pale yellow, halter white.

Wing: hyaline; microtrichose, except bare on basal cell bc, posterobasal 1 / 3 of cell c, basal 3 / 5 of cell r 1, basal 1 / 8 of cell r 2 + 3, most of cell br (only microtrichose along vena spuria), slightly more than posterior 1 / 2 of cell bm, anterior 1 / 2 of cell cup, and basomedian 2 / 3 of alula.

Legs: femora blackish brown with yellow apices; yellow setulose. Tibiae pale yellow at basal 2 / 3, pale brown at apical 1 / 3, and blackish brown around cicatrix; yellow setulose except black setulose on inner side at apical 1 / 3. Tarsi pale brown; black setulose dorsally, yellow setulose laterally and ventrally. Coxae and trochanters brown; pale yellow to white setulose.

Abdomen. Tergites blackish brown, mostly shiny except for large part of tergite 3. Tergite 1 white setulose. Tergite 2 shiny except for small median dull macula, with distinct metallic sheen at lateral 1 / 4; whitish setulose, except for some black setulae along lateral margin. Tergite 3 dull black, except for narrow fascia with bronze sheen along posterior and lateral margins; dull part short black setulose except for pale setulae posteromedially, shiny parts longer yellowish white setulose. Tergite 4 entirely shiny but not metallic; mostly short black setulose, but longer pale yellow to whitish setulose along lateral margins and on pair of large posteromedian patches. Sternites blackish brown; all sternites white setulose. Genitalia as in Figs 150–153 : phallus with large, subapical flag-like projection.

Female (based on paratype) As male, except for usual sexual dimorphism and following differences. Scutum largely black setulose, except for yellowish setulae along anterior margin. Tergites somewhat paler brown than in male.

Diagnosis.

Body length: male 6.0–7.0 mm (n = 19), female 8.5–9 mm (n = 3). The combination of a black face with a contrasting colour pattern on the tibiae (Fig. 7 ) sets this species apart from all other species in the genus. Besides, the male genitalia are very distinct in the fact that the phallus carries a ‘ flag-like’ apicodorsal projection (Figs 150–153 ).

Notes.

This is the only known species of Serichlamys in which the male has a flag-like appendix on the phallus. Some slight variation occurs in the shape of this appendix (Figs 150–153 ), but this is considered to be intraspecific. Little variation among the specimens (mostly subtle differences in colouration) was noted in external characters, except that the colour of setulosity on the scutum may vary between entirely golden yellow to mostly black. No habitat information is indicated on the labels of the specimens, but the localities suggest that they were found at the margins of tropical rain forest.

Etymology.

The specific epithet is a noun in apposition composed of the Latin words vexillum (flag) and phallus (penis). It refers to the characteristic dorsal projection on the phallus in males of this species.

Molecular data.

A specimen from Ecuador and another from Peru were sequenced. Both DNA barcodes cluster together with high-support (BS = 100) and they have a similarity of 97.833 %.

Distribution.

This species is known from Ecuador (n = 13), Peru (n = 1) and Panama (n = 1). In the first two countries, it has been found at elevations between 300 and 1100 meter, at slopes of the Andes and in lowland rainforest. In Panama it was found in rainforest at 800 meters of altitude. Based on these records, it can be expected that this species also occurs in Colombia.

Figures

Figures 5–12. 5, 6 colour of face of Serichlamys species 5 black (S. chloraspis Reemer, sp. nov. male, holotype) 6 yellowish brown (S. serpentiphallus Reemer, sp. nov. male, holotype) 7–9 hind tibiae of Serichlamys species 7 with contrasting colour pattern (S. vexilliphallus Reemer & Mengual, sp. nov. male, holotype) 8 uniformly yellowish brown (S. mitis (Curran, 1940) male, specimen MR 1576) 9 dark (S. pallitarsis Reemer & Mengual, sp. nov. male, holotype) 10–12 antenna of Serichlamys species 10 postpedicel pale brown with apical 1 / 3 dark (S. mitis (Curran, 1940) male, specimen MR 1576) 11 postpedicel entirely dark brown (S. varicaudata Reemer & Mengual, sp. nov. male, holotype) 12 postpedicel entirely orange (S. pallitarsis Reemer & Mengual, sp. nov. female, paratype).

Figures 126–130. Serichlamys vexilliphallus Reemer & Mengual, sp. nov. male, holotype 126 habitus, dorsal 127 habitus, lateral 128 head, frontal 129 head, lateral 130 head, dorsal.

Figures 150–154. Serichlamys vexilliphallus Reemer & Mengual, sp. nov. male genitalia, with variations in shape of distal part of phallus 150 holotype (Ecuador) 151 paratype, specimen code MR 1483 (Ecuador, coll. RMNH) 152 specimen code MR 1482 (Panama, coll. CSCA) 153 specimen code MR 565 (Peru, coll. RMNH) 154 Serichlamys xanthocnemia Reemer, sp. nov. male, holotype, genitalia.