Zygomyia uniordata, Kurina & Õunap, 2023

Kurina, Olavi & Õunap, Erki, 2023, Morphological and molecular data reveal fifteen new sympatric Zygomyia Winnertz, 1864 (Diptera: Mycetophilidae) species from Ecuador, Zootaxa 5227 (1), pp. 1-49 : 31

Zygomyia uniordata sp. nov.

( Figs 2D , 16A–E , 21D )

urn:lsid:zoobank.org:act:90DA349E-4B04-42BB-901D-6812229C2010

Type material. HOLOTYPE ♂, ECUADOR, Napo Province, Yanayacu Biological Station , 0.5956S 77.8942W, alt. 2234 m, 29.viii–3.ix.2019, X. Mengual, T. Salden leg., double Malaise trap (mounted from alcohol with terminalia in glycerine, INABIO; specimen code: MECN-EN-DIP-4871; one fore leg used for DNA extraction, GenBank accession number: OP747435 ).

Diagnosis. Zygomyia uniordata somewhat resembles Z. chavantesi in having the costal vein extended beyond R 4+5. However, this extent is considerably smaller in the new species (cf. Key to species, above). Moreover, Z. uniordata has the ventral branch of the gonostylus undivided (divided by a medial deep notch in Z. chavantesi ). The gonocoxite has a single row of sub-marginal strong setae posteroventrally that distinguishes Z. uniordata from other Neotropical species.

Description. Male (n = 1). Body length 2.0 mm. Wing length 1.8 mm; ratio of length to width 2.57.

Head. Dark yellow with numerous dark setae. Two ocelli close to eye margins. Clypeus yellow, somewhat lighter than head. Mouth-parts yellow to light brown. Palpus with all segments light brown, ratios of three apical segments 1:1.2:2.00. Scape, pedicel and flagellomeres light brown. Flagellomeres cylindrical, first flagellomere 2.25 × as long as broad, fourth flagellomere 1.75 × as long as broad, apical flagellomere absent in holotype. Flagellomeres with short yellowish setae.

Thorax. Mesonotum dark yellow. Pleural parts yellow with katepisternum somewhat lighter. All bristles and setae on thorax brown. Scutellum with marginal setae, including four strong bristles. Antepronotum with setae, including 6–7 bristles of different lengths. Proepisternum with setae including 2–3 stronger bristles. Anepisternum with a number of posteriorly-directed short setae and 3 bristles of different lengths on dorsal part. Anepimeron with short setae and 2 bristles on dorsal part. Laterotergite with 5–6 dorsally-directed setae medially. Metepimeron with 3–4 setae on posterior part. Halter light brown. Legs yellow. Tarsi appear darker, due to dense brown setation. Whole anterior side of fore coxa, apical fourth of anterior side of mid coxa and all femora clothed in dark setae. Hind coxa with one seta on posterior side apically. Mid femur with 2 apicoventral bristles of different size, hind femur with 4 apicoventral bristles of different size. Mid tibia with 3 a, 5 d (progressively longer towards apex), 1 p and 2 v. Hind tibia with 6 a, 5 d (progressively longer towards apex). Length ratio of femur to tibia for fore, mid and hind legs: 1.22, 1.06, 0.83. Length ratio of tibia to basitarsus for fore, mid and hind legs: 1.64, 1.50, 1.60. Wing membrane hyaline with light brownish tinge, without markings. Veins light brown. R 1 and R 4+5 with strong setae on both sides. Crossvein rm and bM-Cu glabrous. M 1, M 2 and CuA devoid of setae. m-stem twice as long as r-m. Costa extending somewhat beyond R 4+5.

Abdomen. Brown with first two segments laterally somewhat lighter. Terminalia ( Figs 16A–E , 21D ) yellow to light brown. Posteroventral margin of gonocoxites emarginated, with single transverse row of sub-marginal strong setae posteriorly and a few additional setae laterally. Ventral branch of the gonostylus simple, posteriorly rounded, about two times as long as wide, with (1) row of strong setae along medial margin, and (2) tight aggregation of setae anterolaterally. Dorsal branch of the gonostylus with two lobes: (1) dorsal lobe, small, rounded, with marginal row of setae, and (2) ventral lobe elongated, posteriorly rounded, with aggregation of lateral setae and two pointed sub-apical outgrowths, one laterally and one medially. Aedeagus apically widening and rounded. Parameres broad, apically rounded, extending over aedeagus posteriorly. Gonocoxal apodemes relatively short, apically pointed, broadest at mid length.

Female. Unknown.

Etymology. The name is derived from the Latin, uni- [one or single] and ordo [row or tier], referring to the single transverse sub-marginal row of strong setae on the gonocoxite ventrally.

Figures

FIGURE 2. Habitus of Zygomyia species from Ecuador (all photos, except Z. bicolor, are taken from holotypes). A, Z. spinosa sp. nov.; B, Z. ximoi sp. nov.; C, Z. bicolor Edwards, 1934 (MECN-EN-DIP-4873); D, Z. uniordata sp. nov.; E, Z. napoensis sp. nov.; F, Z. trilobata sp. nov.; G, Z. triseta sp. nov.; H, Z. talpaeforma sp. nov. Scale bars = 1 mm.

FIGURE 16. Zygomyia uniordata sp. nov., male terminalia (holotype, MECN-EN-DIP-4871). A, B, ventral view; C, dorsal view; D, posterior view; E, gonostylus, dorsal view. Scale bar = 0.05 mm (A–D) and 0.02 mm (E).

FIGURE 21. Aedeagal apparatus of Zygomyia species from Ecuador (all photos are taken from holotypes). A, Z. diversiseta sp. nov.; B, Z. spinosa sp. nov.; C, Z. paniculata sp. nov.; D, Z. uniordata sp. nov. Scale bar = 0.1 mm.