Ephydrella novaezealandiae (Tonnoir and Malloch)

Mathis, Wayne N. & Zatwarnicki, Tadeusz, 2025, A review of Ephydrella Tonnoir and Malloch from the New Zealand subregion (Diptera: Ephydridae) with description of a new species, Zootaxa 5673 (2), pp. 227-251 : 242-245

5. Ephydrella novaezealandiae (Tonnoir and Malloch)

Figs. 31–38

Ephydra (Ephydrella) novaezealandiae Tonnoir and Malloch 1926: 8 .— Benham 1905: 308–312 [figures of puparium, larval description].

Ephydrella novaezealandiae .— Cresson 1935: 354 [generic combination].— Miller 1950: 111 [catalog of New Zealand Diptera ].— Harrison 1959: 246–247 [fauna of New Zealand].—Bayly 1969: 107–108, 111 [ecology].— Dumbleton 1969: 43–44 [immature stages].— Carlton 1971: 1–25 [figures of larvae, biology].— Mathis 1989: 647 [Australasian/Oceanian catalog].— Mathis and Zatwarnicki 1995: 248 [world catalog].— Winterbourn et al. 2000: 82 [review, larvae].— Hughes et al. 2004: 838, 840 [specimens with Stigmatomyces ephydrae Mercier & Poiss ].

Mydaezealandia glauca Salmon 1937: 360 [ New Zealand. Napier, LT ♂ (designated herein), MONZ].— Salmon 1950: 2 [synonymy with E. spathulata ]. syn. nov.

Diagnosis.—This species is distinguished from congeners by the following combination of characters: Moderately large shore flies, body length 4.30–4.70 mm. Body grayish brown to brown; at least abdomen and mesonotum green or brown, more sparsely microtomentose, subshiny to shiny.

Head ( Figs. 31–32 ): Frons and face grayish brown; mesofrons shiny, metallic brown; parafrons blackish brown to brown, dull, microtomentose, dull. Gena-to-eye ratio 0.37–0.40.

Thorax ( Fig. 33 ): Mesonotum generally microtomentose, grayish brown to brown, with faint indication of more grayish longitudinal stripes. Acrostichal setulae, except for posterior pair, small, sparse, and not organized into rows; scutellum longer than wide, pointed apically. Costal vein ratio 0.24; M 1 vein ratio 0.71. Legs blackish brown with basitarsomere of middle leg yellowish brown.

Abdomen ( Figs. 34–37 ): Tergites microtomentose, grayish green to grayish blue, mostly dull but with slight metallic reflections. Male terminalia ( Figs. 34–37 ): Epandrium in posterior view ( Fig. 34 ) conspicuously higher than wide, dorsal margin acutely arched, height of cercal cavity about 1/3 overall height of epandrium, epandrium in lateral view ( Fig. 35 ) with dorsal portion robustly formed, tapered to broad, angulate dorsum, ventral portion semirectangular, anterior margin evenly concave; cercus in posterior view ( Fig. 34 ) drop-like, tapered dorsally, in lateral view ( Fig. 35 ) semihemispherical; surstylus in posterior view ( Fig. 34 ) more or less robustly digitiform, expanded slightly from base, widest at midlength, thereafter slightly tapered to rounded apex, surstyli in lateral view ( Fig. 35 ) nearly straight on apical 2/3, parallel sided, apex rounded; medioventral process in posterior view ( Fig. 34 ) well developed, triangular; phallus in lateral view ( Fig. 35 ) longer than high, more or less V-shaped, dorsal margin shallowly sinuous, basal margin with a somewhat rectangular protrusion, twice as high as wide, corners rounded, in ventral view ( Fig. 36 ) elongate, length almost 3X width, lateral margins pedunculate, base rectangular with rounded corners, apical fourth tapered to a point; phallapodeme in lateral view ( Fig. 37 ) with keel twice as long as wide, keel broadly rounded, ventral extension (to postgonite) and dorsal extension (to base of phallus) about equal in length, in ventral view ( Fig. 36 ) narrowly V-shaped, becoming narrower apically; postgonite+hypandrium in lateral view ( Fig. 37 ) with base as a dorsally curved tapered projection, dorsal portion extended apically as a narrow, curved, gradually tapered band, ventral portion somewhat rectangular, dorsal margin nearly straight, ventral margin very shallowly arched, apical margin concave, in ventral view ( Fig. 36 ) with lateral margins broadly projected, rounded, narrowed basally and apically, apical extension more elongate than base, with a sharp recurve laterally at midlength, thereafter apically more sharply narrowed to acute apical point.

Primary Type Material.— The holotype male of Ephydra (Ephydrella) novaezealandiae Tonnoir and Malloch is labeled “[ New Zealand.] Christchurch 17 Feb. 1922 A. Tonnoir / TYPE Ephydra novae-zealandiae n.sp. ♂ A. Tonnoir det. [pink; species name, gender symbol, and “n.sp.” handwritten].” The holotype is double mounted (minuten wound around base pin, bent at 90° angle upward), is in excellent condition (apex of abdomen removed, mounted on a small celluloid slide that is attached to the main pin beneath the locality label; right arista missing, few setae missoriented), and is deposited in the NZAC .

The lectotype male of Mydaezealandia glauca Salmon , here designated to stabilize and make more universal the use of this name, is labeled “[ New Zealand.] NAPIER 3/4/35 [3 Apr 1935; date handwritten]/ I.C. Edmundson [handwritten]/red disk/red disk/Hydaezealandia glauca Type Det. J. T. Salmon [handwritten]/ HOLOTYPE [red].” The lectotype is directly pinned, is in fair condition, and is deposited in the MONZ .

Type Locality.— Australasian : New Zealand. South Island. Christchurch (43°31.9'S, 172°38.2'E) .

Specimens Examined from New Zealand. — NORTH ISLAND . AK : Mangere (36°58.1'S, 174°47.5'E), 5 Feb 1962 (1♂, 2♀; NZAC); Mangere, Auckland Metropolitan Drainage Board Area (36°58.1'S, 174°47.5'E), 4 May 1959, K. A. J. Wise (7♂, 10♀; NZAC); Maketu (37°45.5'S, 176°27'E; pool on salt meadow), 31 May 1970, J. Gillespie (2♂, 2♀; NZAC); Miranda (37°11.1'S, 175°18.9'E; muddy margins of salt march; Stigmatomyces ephydrae Mercier & Poiss on mesonotum and legs of male and female), 27 Mar 2000, A. Weir, C. Carlton., AW934; Orrs Beach, Papatoetoe (36°59.8'S, 174°49'E), 11 Sep 1966, K. A. J. Wise (1♀; AMNZ); Puketutu Island (36°57.8.5'S, 174°44.7'E; near Mangere), 6 Apr 1969, B. P. May (5♂, 7♀; NZAC). BP : Bay of Plenty, Tauranga Harbour (37°40.6'S, 176°12'E; behind airport), 21 May–1 Aug 1970, J. Gillespie (5♂, 3♀; NZAC). HB: Clifton (39°38.5'S, 176°59.6'E), 10 Nov 1922, J. W. Campbell (9♂, 10♀; NHMUK). ND : Mokohinau, Burgess Island (35°55'S, 176°06'E), 24 Aug 1955, R . A. Harrison (2♀; LUNZ); Sandy Bay (beach; 35°33.4'S, 174°28.5'E), 6 Oct 2002, D. and W. N. Mathis (4♀; USNM); Whananaki South (mangrove and beach; 35°31.1'S, 174°27.2'E), 6–8 Oct 2002, D. and W. N. Mathis (5♂, 6♀; USNM). WN : Owhiro Bay (S of Wellington; 41°06.2'S, 174°55.1'E), 10 Nov 1977, E. I. Schlinger (2♂; NZAC); Pauatahanui (E side of Porirua Harbour; 41°06.5'S, 174°51.3'E), 11 Nov 1977, E. I. Schlinger (5♂, 2♀; NZAC); Waikanae Beach (40°52.3'S, 175°0.5'E), 6–7 Jan 2004, W. N. Mathis (1♂; USNM). WO : Raglan (37°49.6'S, 174°53.6'E; freshwater pond), 17 May 1971, J. Gillespie (1♂, 2♀; NZAC); Miranda Beach (37°10.9'S, 175°19.4'E), 3 Dec 1950, K. A. J. Wise (3♂, 1♀; NZAC) .

SOUTH ISLAND. CO: Sutton Salt Lake (45°34.6'S, 170°05.2'E), 11 Nov 1989, A. C. Harris (6♂, 8♀; OMNZ) . DN: Otago Peninsula, Hoopers Inlet, Allans Beach Road (45°52.0'S, 170°41.3'E); 13 Jan 2004, W. N. Mathis (11♂, 7♀; USNM) ; Otago Peninsula, Hoopers Inlet (45°51.1'S, 170°39.7'E); 13 Jan 2004, W. N. Mathis (9♂, 2♀; USNM) ; Warrington (45°42.6'S, 170°36'E; beach), 11 Dec 1977, E. I. Schlinger (3♂, 5♀; NZAC) . MC: Avon Heathcote (43°32.7'S, 172°43.8'E; mud flats), 5 Jan 1977, P. G. McGregor (2♂, 4♀; CMNZ) ; Banks Peninsula, Akaroa (43°48.2'S, 172°58.1'E), 10 Dec 1924, A. Tonnoir (1♂; paratype; CMNZ) ; Banks Peninsula, Port Levy (43°39'S, 172°49'E), 26–28 Feb 1999, S. A. Marshall (1♀; GUE) ; Banks Peninsula, Lake Forsyth ( Rt. 75) (43°46.8'S, 172°46.8'E), 15 Dec 1986, B. J. and F. C. Thompson (8♂, 9♀; USNM) ; Banks Peninsula, Robinsons Bay ( Rt. 75; beach; 43°45.7'S, 172°57.6'E), 15 Dec–31 Jan 1986, 2004, W. N. Mathis, B. J. and F. C. Thompson (10♂, 2♀; USNM) ; Birdings Flat (43°49.6'S, 172°42.5'E), 18 Oct 2002, D. and W. N. Mathis (28♂, 7♀; USNM) ; Brooklands Lagoon (43°25.8'S, 172°42.4'E), 17 Oct 2002, D. and W. N. Mathis (2♂, 2♀; USNM) ; Charteris Bay (43°39.9'S, 172°42.5'E), 21 Sep 1925, A. Tonnoir (1♂, 1♀; paratypes; CMNZ) ; Christchurch (43°31.9'S, 172°38.2'E), 17 Feb 1922, 1 Oct 1925, A. Tonnoir (5♂, 5♀; paratypes; AMNZ, CMNZ, NZAC) ; Crom McCormack's Bay , east outlet (43°33.4'S, 172°43.3'E), 24 Dec 1976, P. G. McGregor (1♀; CMNZ) ; Governors Bay (43°37'S, 172°38.6'E), 18 Sep 1922, J. F. Tapley (4♂, 6♀; CMNZ) ; Lake Forsyth (43°47.4'S, 172°45.5'E), 18 Oct 2002, D. and W. N. Mathis (2♀; USNM) . NN: Farewell Spit (40°31'S, 172°52'E), 4–11 May 1977 (2♂, 2♀; CMNZ) ; Nelson (41°17.9'S, 173°14.7'E), Jul 1927, A. Tonnoir (1♂, 2♀; NZAC) ; Nelson (airport; 41°18.2'S, 173°13.6'E), 11 Feb 1998 , V. Hollmann, W. N. Mathis (1♂, 9♀; NZAC, USNM) . WN: Island Bay , Wellington (41°20.6'S, 174°46.3'E), 4 Feb 1921, G . V. Hudson (1♀; NHMUK) .

Distribution ( Fig. 38 ).—Australasian/Oceanian: New Zealand (AK, BP, CO, DN, MC, ND, NN, WN, WO).

Natural History.—Larvae of this species live in brackish water associated with inland ( Bayly 1967) and tidal estuaries ( Dumbleton 1969, Carlton 1971) with 5.5–16% salinity. The initial description and illustration of the puparium with a strong ventral groove and a bifid “tail” ( Benham 1905) is of this species ( Bayly 1967, Dumbleton 1969). This may be the only species of Ephydrella that is found at inland sites with saline water.

Carlton (1971) found that larvae consumed green algae and diatoms on Salicornia and that the food had been digested before reaching the midgut. At room temperatures (17–25°C) it took 23–31 days for males and females respectively to go from egg to adult. Adult flight is limited below 16°C, and females did not oviposit when temperatures were 19–23°C.

Remarks.— Salmon(1937) described the junior synonym, Mydaezealandia glauca , and then (1950) synonymized his species with E. spathulata Cresson , probably without having examined the holotype of E. spathulata . As part of this study, we studied the primary types of all species, and based on these observations, we propose the new synonymy noted above. We directly compared specimens, especially structures of the male terminalia, which are fortunately exposed in most male specimens of the type series.

This species is distinguished from congeners, especially E. spathulata , by the following combination of characters: facial protrusion mostly unicolorous; at least abdomen and mesonotum green or brown, more sparsely microtomentose, subshiny to shiny; acrostichal setulae irregularly arranged in 4–5 rows, inconspicuous; legs blackish brown with basitarsomere of middle leg yellowish brown; surstylus digitiform, more or less parallel sided.

Figures

FIGURES 31–33. Head and thorax of Ephydrella novaezealandiae (Tonnoir & Malloch). 31. Head, anterior view. 32. Same, lateral view. 33. Thorax, dorsal view. Scale bar = 0.5 mm.

FIGURES 34–37. Male terminalia of Ephydrella novaezealandiae (Tonnoir & Malloch; specimens from New Zealand. Otago Peninsula, Hoopers Inlet, 13 Jan 2004, W. N. Mathis). 34. External structures, posterior view. 35. Same, lateral view. 36. Internal structures, ventral view. 37. Same, lateral view. Scale bar = 0.1 mm.

FIGURES 38–43. Distribution maps and male terminalia of Ephydrella. 38–39. Distribution maps. 38. E. bicolor sp. nov. (stars) and E. novaezealandiae (Tonnoir & Malloch) (circles). 39. E. spathulata Cresson (stars) and E. thermarum Dumbleton (circles). 40–43. Male terminalia of E. spathulata Cresson (specimen from New Zealand. Berwen Station, 2 Feb 2002, R. P. Macfarlane). 40. External structures, posterior view. 41. Same, lateral view. 42. Internal structures, ventral view. 43. Same, lateral view. Scale bar = 0.1 mm.