Afrosyrphus varipes Curran, 1927

Mengual, Ximo, Ssymank, Axel, Skevington, Jeffrey H., Reemer, Menno & Ståhls, Gunilla, 2020, The genus Afrosyrphus Curran (Diptera, Syrphidae), with a description of a new species, European Journal of Taxonomy 635, pp. 1-17 : 12-13

Afrosyrphus varipes Curran, 1927

Figs 1–2 , 3A, C , 4A, D , 5A , C–E, 6

Afrosyrphus varipes Curran, 1927: 50 (type locality: Kisangani [=Stanleyville], Democratic Republic of the Congo; holotype, ♂, AMNH, by monotypy).

Differential diagnosis

This species can be distinguished from A. schmuttereri sp. nov. as stated in the identification key. Overall a smaller species with slightly narrower abdomen, paler pilosity on calypter fringe, scutum and abdominal segments, and male frontal triangle with pale pruinosity along eye margin ( Fig. 4D ). Male genitalia as in Fig. 5 C–E, with ventrally pointed surstyli and postgonites with a large triangular posterodorsal process (see also Vockeroth 1969: fig. 29). Females are also lighter than in A. schmuttereri sp. nov. Tergite 2 is entirely orange in A. varipes (with posterior black fascia in A. schmuttereri sp. nov.), the femora are only slightly darker than the tibiae (femora darker than tibiae in A. schmuttereri sp. nov.), and the face is pale in background colour (black in A. schmuttereri sp. nov.). Both sexes have similar hind legs. The hind first tarsomere (= metabasitarsomere) appears dark and bristly due to the presence of long, black pile ( Fig. 5A ).

Material examined

Holotype

DEMOCRATIC REPUBLIC OF THE CONGO • ♂; Tshopo Province , Kisangani [= Stanleyville]; 1° N, 25.1667° E; ca 460 m a.s.l.; Mar. 1915; Lang and Chapin leg.; based on image at http://research.amnh. org/iz/types_db/details.php?specimen_id=2410; AMNH.

Other material

CAMEROON • 1 ♂, 2 ♀♀; Adamaoua Province, Ngaoundéré, Ranch de Ngaoundaba ; 7.12944° N, 13.69556° E; 1265 m a.s.l.; 12 May 2006; A. Ssymank leg.; specimen identifiers: ZFMK-DIP-00015968 to 00015970 ; ASPC • 1 ♀; same collection data as for preceding; specimen identifier: ZFMK- DIP-00015971 ; GenBank: MN662551 ; ZFMK .

DEMOCRATIC REPUBLIC OF THE CONGO • 1 ♂; Tshopo Province , Yambuya; 1.263669° N, 24.552813° E; ca 400 m a.s.l.; 24 Nov. 1913; J. Bequaert leg.; specimen identifier: USNM ENT

00114576; USNM • 1 ♂; North Kivu Province, P.N. Albert, Lesse (near Tungudu); 0.75° N, 29.8° E; 760 m a.s.l.; 21 Jul. 1914; J. Bequaert leg.; specimen identifier: RMCA ENT 000034062 ; RMCA .

UGANDA • 1 ♀; Central Region , Entebbe, Kisubi Forest; 0.11928° N, 32.52831° E; ca 1160 m a.s.l.; 24 Apr. 1976; M. Paulus leg.; specimen identifier: CNC DIPTERA 102962 ; GenBank: MN662560 ; CNC .

Genetics

A total of two specimens was successfully sequenced, one sequence with a length of 627 bp ( ZFMK- DIP-0001597, Genbank: MN662551 ) and another one 307 bp long ( CNC DIPTERA 102962, Genbank: MN662560 ). The obtained COI sequences have an uncorrected pairwise distance of 0.33% and differ by 5.54–6.54% from the COI sequences obtained for A. schmuttereri sp. nov.

Distribution

This species has previously been recorded from Cameroon ( Ssymank 2012), DRC ( Curran 1927, 1938b), Angola and South Africa ( Smith & Vockeroth 1980) (see also Dirickx 1998). No specimens from the latter two countries were studied by the present authors, as Smith & Vockeroth (1980) did not provide any information about the records. Here, we present the first records from Uganda. The material from Kenya collected and studied by Schmutterer (1974) was originally identified as A. varipes , but it belongs to A. schmuttereri sp. nov. Consequently, the presence of A. varipes in Kenya needs confirmation, as well as its presence in Angola and South Africa.

MtDNA COI barcodes

The topology of the tree with the highest likelihood ( Fig. 6 ) compared favourably with the Neighbor- Joining tree (not shown). A total of seven specimens were successfully sequenced. The obtained COI sequences have an uncorrected pairwise distance of 0.08–1.52% among the specimens of A. schmuttereri sp. nov., 0.33% between the two specimens of A. varipes and 5.54–6.54% between the two species of Afrosyrphus .

Figures

Fig. 1. Localities where Afrosyrphus schmuttereri sp. nov. was collected. A. Sampling point in the trail to Iyale (Taita Hills, Kenya). B. Sampling point in the Ruhija Section of the Bwindi Impenetrable National Park (Uganda). Red circle indicates exactly where the flower flies were hovering.

Fig. 2. Known distribution of Afrosyrphus varipes Curran, 1927 (red triangles) and Afrosyrphus schmuttereri sp. nov. (black circles).

Fig. 3. A. Afrosyrphus varipes Curran, 1927, ♂ (ZFMK-DIP-00015968), dorsal view. B. Afrosyrphus schmuttereri sp. nov., paratype, ♂ (ZFMK-DIP-00019829), dorsal view. C. Afrosyrphus varipes, ♂ (ZFMK-DIP-00015968), lateral view. D. Afrosyrphus schmuttereri sp. nov., paratype, ♂ (ZFMK- DIP-00019829), lateral view. Scale bars: 1 mm.

Fig. 4. A. Afrosyrphus varipes Curran, 1927, ♀ (CNC DIPTERA 102962), dorsal view. B. Afrosyrphus schmuttereri sp. nov., paratype, ♀ (CNC DIPTERA 102961), dorsal view. C. Afrosyrphus schmuttereri sp. nov., paratype, ♂ (ZFMK-DIP-00019829), dorsal view of head. D. Afrosyrphus varipes, ♂ (USNM ENT 00114576), frontal view of head. Arrows on C and D indicate the frontal triangle. Scale bars: 1 mm.

Fig. 5. A. Afrosyrphus varipes Curran, 1927, ♀ (ZFMK-DIP-00015969), hind leg. Arrow indicates the long black pile on the hind first tarsomere (= metabasitarsomere). B. Afrosyrphus schmuttereri sp. nov., paratype, ♂ (ZFMK-DIP-00019829), hind leg. C–E. Afrosyrphus varipes, ♂ (ZFMK-DIP-00015968), genitalia. C. Epandrium and surstyli, lateral view. D. Hypandrium, postgonites and aedeagus, lateral view. E. Epandrium, cerci and surstyli, dorsal view. F–H. Afrosyrphus schmuttereri sp. nov., paratype, ♂ (ZFMK-DIP-00019829), genitalia. F. Epandrium and surstyli, lateral view. G. Hypandrium, postgonites and aedeagus, lateral view. H. Epandrium, cerci and surstyli, dorsal view. Scale bars: A–B = 1 mm; C–H = 0.25 mm.

Fig. 6. Maximum-likelihood tree (ln L = -2626.879678) based on COI barcodes, using Garli ver. 2.01. Bootstrap support values are depicted at the nodes (only>50).