Phthinia oliveirae Fitzgerald

Fitzgerald, Scott J., 2017, Phthinia Winnertz (Diptera: Mycetophilidae): new species and records from the Neotropical and Oriental regions, Zootaxa 4231 (1), pp. 107-113 : 110

Phthinia oliveirae Fitzgerald n. sp.

Figs. 3–4

Type material. Holotype: ♂ missing terminal flagellomeres of left antenna, glued directly to side of pin [ CNCI], “ Puerto Cisnes , Aysén, CHILE, 15–28.II.61 ” / “ L. E. Pena ” / “ HOLOTYPE, Phthinia oliveirae Fitzgerald ” [red label], terminalia dissected.

Diagnosis. Phthinia oliveirae can be distinguished from other Phthinia species by the following combination of characters: Sc long, reaching level of Rs distally; gonocoxite with a single distal (posterior) projection ( Figs. 3– 4 ); gonostylus elongate, parallelogram-like, apically bifurcate, with apical anteriorly directed point visible in both dorsal and ventral view ( Figs. 3–4 ), and black, posteriorly directed, apically acute tooth visible only in ventral view ( Fig. 4 ).

Description. Male. Body length: [approx. 5.0 mm] (n=1). Coloration. Light brown; abdomen and head slightly darker. Head. Ocelli not visible due to orientation of head/antennae. Fourteen elongate flagellomeres; first flagellomere longer, approx. 1.2 times the length of flagellomere 2. Thorax. Laterotergite bare. Scutellum with numerous short setae and 4 longer, stronger setae (the apical two longest and strongest). Legs. First tarsomere of foreleg approx. 2.1 times length of foretibia. Hind tibia with 1–2 minute anterior setae, 22–23 minute dorsal setae, and 4 minute posterior setae (n=1); Wings. [approx. 4.0 mm] (n=1). Membrane with macrotrichia; microtrichia also present between more widely spaced macrotrichia. Sc long; reaching level of Rs distally. C extending about 1/3 of the distance between Rs and M1; base of Rs just under 1/2 length r-m; r-m slightly shorter than stem of M; most of M1 weakly sclerotized and unpigmented (recognizable by crease and row of minute closely set setae present on other veins). A1 diverging only slightly from stem of CuA. Abdomen. Terminalia ( Figs. 3–4 ). Terminalia concolorous with abdomen. Cerci short, lobate, apically rounded, with small setae. Hypoproct short, medially divided and cerci-like, narrowly rounded and densely setose apically. Gonocoxites ventrally partially subdivided by pair of sutures level with posteroventral border of ventromedially fused gonocoxites, thus forming gonocoxal subdivisions “Section 1” and “Section 2” as noted by Söli (1997) in some mycetophilids ( Fig. 4 ). In dorsal and ventral views gonocoxites developed posteriorly beyond point of dorsal articulation of gonostylus into an apical, posteriorly-directed, medially-curved, digitate, setose lobe ( Figs. 3–4 ). In dorsal view, gonocoxites with a small, narrow, dorsomedially-curved, black-tipped, spine arising on small rounded lobe just dorsal to articulation point of gonostylus and a larger, short, stout, broad, black, medially-directed tooth arising on the median surface of the gonocoxite just anterior to the articulation point of gonostlyus ( Fig. 3 ). Gonostylus elongate, parallelogram-like, apically bifurcate, with apical anteriorly directed point visible in both dorsal and ventral view ( Figs. 3–4 ), and black, posteriorly directed, apically acute tooth visible only in ventral view ( Fig. 4 ). Parameres a pair of thin, weakly-sclerotized, elongate, apically rounded, slightly divergent lobes ventral to hypoproct. Ventral to parameres, aedeagal complex subquadrate. Posterolateral edges of epandrium (T9) broadly rounded, without strong posteriorly-directed digitate lobes; sclerite relatively short with broad U-shaped posterior margin ( Fig. 3 ).

Female. Unknown.

Comments. Phthinia oliveirae is most similar to P. furcata Freeman and will key to this species in the key to Neotropical Phthinia in Oliveira & Amorim (2010) , but can be distinguished by the differences in the structure of the gonostylus. The gonostylus of P. furcata is simple, digitate, apically rounded ( Freeman 1951, fig. 108), whereas the gonostylus of P. oliveira is stouter, parallelogram-like, apically bifurcate.

Etymology. The specific epithet honors Sarah Siqueira Oliveira for her contributions to our knowledge of Neotropical Sciaroidea.

Figures

FIGURES 1 – 4. Male terminalia. Fig. 1 – 2. P. amorimi n. sp., [holotype male]; position and density of setae indicated by alveoli; apex of right gonostylus excluded for clarity. 1. Dorsal view. 2. Ventral view. Fig. 3 – 4. P. oliveirae n. sp., [holotype male] with one side completely excluded for clarity; position and density of setae indicated by alveoli. 3. Dorsal view. 4. Ventral view. Abbreviations: Gs, gonostylus; Gx, gonocoxites; T 9, tergite 9.