Dasyrhicnoessa ferruginea ( Lamb, 1914 )

Munari, Lorenzo, Kirk-Spriggs, Ashley H. & Mcgregor, Gillian K., 2020, The beach flies of the Mascarene Islands (Diptera: Canacidae: Tethininae), Zootaxa 4853 (2), pp. 183-198 : 190-191

Dasyrhicnoessa ferruginea ( Lamb, 1914)

Figs 11 , 18 , 23 , 26 , 31 .

Distribution. Afrotropical: Kenya, Madagascar, Mascarenes ( Mauritius *, Réunion *, Rodrigues*), Oman, Seychelles (Aldabra, Anonyme, Aride, Astove, Long, Mahé,?Praslin), Tanzania, United Arab Emirates. Australasian/Oceanian: Australia (Queensland), Caroline Islands (Yap), Mariana Islands ( Guam, Saipan), Palau, Papua New Guinea. Oriental: China ( Hong Kong - Lantau), Malaysia (Sabah, Singapore), Philippines (Balabac, Busuanga, Calicoan, Culion, Leyte, Masbate, Mindanao, Negros Oriental, Palawan), Singapore. Palaearctic: Qatar, Saudi Arabia. South Indian Ocean Islands: Amsterdam Island.

Material examined (all “A.H. Kirk-Spriggs & B.S. Muller, sweeping intertidal zone and coastal vegetation”, unless otherwise stated). La Réunion: 4♂, 1♀, Pointe de Tremblet , 21°17′34″S, 55°48′21″E, 0–9 m, 9.xi.2015 , M.J. Ebejer, general sweeping; intertidal zone & sandy beach (deposited MJEC). Mauritius: 23♂, 17♀, Black River, Le Morne Brabant , 20°27′32″S, 57°19′42″E, 1–3 m, 28.i.2018 (1♂ deposited LMC) ; 5♂, 4♀, Black River, Petite Case Noyale , 20°24′23″S, 57°22′10″E, 1–3 m, 28.i.2018 (2♂, 1♀ deposited LMC) ; 1♀, Flacq, Poste de Flacq, 20°09′40″S, 57°44′49″E, 1–3 m, 26.i.2018 ; 2♂, Flacq, Poste Lafayette , 20°07′02″S, 57°45′05″E, 1–3 m, 30.i.2018 ; 60♂, 86♀, Grand Port, Grand Sable , 20°19′12″S, 57°46′12″E, 1–3 m, 27.i.2018 (2♀ deposited LMC) ; 2♀, Grand Port, Pointe d’Esny , 20°25′28″S, 57°43′22″E, 1–3 m, 27.i.2018 ; 50♂, 56♀, Pamplemousses, Le Goulet , 20°06′14″S, 57°31′02″E, 1–3 m, 30.i.2018 (1♂, 1♀ deposited LMC) ; 3♂, Pamplemousses, Trou aux Biches , 20°02′36″S, 57°32′14″E, 1–3 m, 29–30.i.2018 ; 1♂, 4♀, Rivière du Rempart, Grand Gaube , 20°01′00″S, 57°40′55″E, 1–3 m, 29–31.i.2018 ; 1♀ (cf.), Rivière du Rempart, Pointe des Lascars , 20°05′14″S, 57°42′26″E, 1–3 m, 31.i.2018 ; 2♂, 6♀, Savanne, Bel Ombre , 20°30′00″S, 57°23′34″E, 1 m, 11.xii.2016 , sweeping coastal rocks and sandy beach. Rodrigues: 1♂, Anse aux Anglais , 19°40′15″S, 63°26′19″E, 1–3 m, 10.ii.2018 ; 1♂, Baie du Nord , 19°42′33″S, 63°22′20″E, 1–3 m, 9.ii.2018 ; 1♂, 4♀, Petite Gravier , 19°43′40″S, 63°29′03″E, 1–3 m, 10.ii.2018 (1♂ deposited LMC) ; 3♂, 5♀, Plaine Corail , 19°46′05″S, 63°22′36″E, 1–3 m, 9.ii.2018 (all deposited BMSA, unless otherwise stated).

Comments: A rather common Indo-Pacific species, characterised primarily by the peculiar chaetotaxy pattern of the posteroventral armature of the male mid femur (see above identification key and Fig. 11 ). Additionally, the morphological form of the external male terminalia is also distinctly dissimilar from that of the other two Mascarenian species of Dasyrhicnoessa (compare Fig. 18 with Figs 16, 17 ). In fact, D. insularis ( Aldrich, 1931) and D. vockerothi Hardy & Delfinado, 1980 , share a similar structure of the surstyli with each other ( Figs 16, 17 ), so much so, that they can be assigned, along with a few other Pacific species, to a thus far unnamed species-group. Dasyrhicnoessa ferruginea is newly recorded here from the Mascarenes.

Figures

FIGURES 10–12. Mid femora and tibiae of male beach flies (posterior views). 10. Dasyrhicnoessa insularis (Aldrich). 11. D. ferruginea (Lamb). 12. D. vockerothi Hardy & Delfinado. Scale bar = 0.3 mm.

FIGURES 13–18. Male terminalia of beach flies. 13. Afrotethina aurisetulosa (Lamb), right surstyli in posteromesial view (after Munari 1988). 14. Pseudorhicnoessa rattii Munari, left lateral view (after Munari 1981). 15. Same, P. spinipes Malloch (after Sasakawa 1974). 16. Same, Dasyrhicnoessa insularis (Aldrich) (after Foster & Mathis 1998). 17. Same, D. vockerothi Hardy & Delfinado (after Sasakawa 1995). 18. Same, D. ferruginea (Lamb). Scale bars: 13 = 0.05 mm; 14–15 = 0.3 mm; 16–18 = 0.1 mm. Abbreviations: a sur—anterior surstylus; p sur—posterior surstylus.

FIGURES 22–24. Distribution maps of beach flies on La Réunion sampled in 2015. 22. Afrotethina aurisetulosa (Lamb). 23. Dasyrhicnoessa ferruginea (Lamb). 24. D. insularis (Aldrich).

FIGURES 25–29. Distribution maps of beach flies on Mauritius sampled in 2018. 25. Afrotethina aurisetulosa (Lamb). 26. Dasyrhicnoessa ferruginea (Lamb). 27. D. insularis (Aldrich). 28. D. vockerothi Hardy & Delfinado. 29. Pseudorhicnoessa rattii Munari.

FIGURES 30–34. Distribution maps of beach flies on Rodrigues sampled in 2018. 30. Afrotethina aurisetulosa (Lamb). 31. Dasyrhicnoessa ferruginea (Lamb). 32. D. insularis (Aldrich). 33. D. vockerothi Hardy & Delfinado. 34. Pseudorhicnoessa rattii Munari.