Dixella jailtoi, Corrêa & Scarpa & Pinho & Gil-Azevedo, 2024

Corrêa, Caio Cezar Dias, Scarpa, Priscila Luiza, Pinho, Luiz Carlos & Gil-Azevedo, Leonardo Henrique, 2024, Three New Species Of Dixella Dyar & Shannon (Diptera: Dixidae) From Santa Catarina, Brazil, Zootaxa 5433 (3), pp. 321-338 : 327-331

Dixella jailtoi sp. nov.

( Figs. 5–6 )

Type Material. HOLOTYPE: ♂ (slide)—[ MNRJ40888 ] BRAZIL, Santa Catarina, Grão Pará, Parque Estadual da Serra Furada , S28º09’07” W49º23’18”, 16/XI/2012 – 08/I/2013, Malaise trap, LC Pinho, MC Novaes & MF Haddad col. ( MNRJ) . PARATYPES: 1♂ (96% ethanol)—[ MNRJ40975 ] Brazil, Santa Catarina, Grão Pará, Parque Estadual da Serra Furada , Janela stream, S28º09’07” W49º23’18”, 7/V –9/VI /2013, Malaise trap, LC Pinho, AP Amaral, MO Bessel & AM Will col. ( MZSP) ; 1♂ (96% ethanol)—[ MNRJ40976 ] Brasil, Santa Catarina, Grão Pará, Rio Braço Esquerdo , S28º09’01” W49º21’21”, 16/XI/2012, Light trap, LC Pinho, LS Gomes & AL Schlindwein col. ( MNRJ) [without terminalia] ; 1♂ (96% etanol and slide)—[ MNRJ40977 ] same data as previous, terminalia in slide ( MNRJ) .

Diagnosis. Male adult with katepisternum pale with a light brown spot in the antero-medial portion ( Fig. 5D ); gonostylus cylindrical and subtly curved, scattered sensilla on the external margin, 1–2 elongated setae in the subapical portion, and tapered apical portion with one stout seta ( Fig. 6G ).

Description. Male. Body length: 2.7 mm (n = 3) ( Fig. 5A ) Head ( Fig. 5B ) uniformly brown with lateral margin yellow close to eyes, row of short setae on the posterolateral portion, and setae around the margin of eyes in the posterior portion. Antenna ( Fig. 5C ) yellow to light brown, setose, and 0.6x length of wing. Scape yellow, collar-like, row of ca. three setae on posterolateral portion and ca. five setae on apical portion. Pedicel light brown, globose, setose, and 0.45x length of flagellomere I. Flagellum with 14 flagellomeres. Flagellomere I cylindrical, 1.65x length of flagellomere II. Flagellomere II smaller than flagellomere III. Flagellomeres III to XIV decreasing in length. Flagellomere XIV with pair of divergent apical setae. Clypeus yellow, short, 1.2x wider than long and ca. eight setae in the medial to apical portion. Maxillary palpus yellow and 5-segmented; maxillary palp V claviform. Maxillary palpus ratio (I–V): 1, 1.1, 2.6, 2.6, 3. Thorax ( Fig. 5D ). Scutum yellow with light brown medial stripe extending from anterior to medial margin with a little invagination at posterior portion, and light brown lateral stripe extending from prescutal to prescutellar area. Acrostichal setae originating from anterior portion and reaching the medial portion; dorsocentral setae complete; antealar area with four elongated setae. Antepronotum light brown with ca. five setae. Postpronotum yellow with ca. five setae. Anterior and posterior anepisternum light brown. Katepisternum yellow, bare, with a light brown spot at medial region of the anterior portion. Anepimeron yellow with the dorsal portion light brown. Laterotergite, metepimeron and metepisternum light brown. Meron light brown. Scutellum yellow with ca. 10 elongate setae. Mediotergite light brown. Legs ( Fig. 5A ) Ratio (n = 4): fore leg (11.4, 11.6, 8.6, 3.2, 2, 1, 1.4), mid leg (14.9, 14.4, 11, 4.1, 2.5, 1, 1.3) and hind leg (10.1, 11, 9.4, 3.3, 2.3, 1, 1.1). Coxae yellow with the basal margin light brown; fore and mid coxae with setae anteriorly, and hind coxa anterolaterally. Trochanters light brown. Fore leg light brown with yellow basal portion of femur. Mid leg uniformly light brown. Fore and mid tibiae swollen apically; fore tibia with a patch of elongated setae on bulge. Hind leg light brown with yellow basal and medial portion of femur; hind tibia strongly swollen apically, bulge with a patch ca. 20–30 thickened setae, with a longitudinal cleft on inner portion and a simple apical spur. Claws pectinate with basal combs. Foretarsal claw: inner claw with four ventral teeth, and outer claw with three ventral teeth, and basal comb with elongate teeth on both claws. Mesotarsal claw: inner claw with three ventral teeth and basal comb with elongate teeth; and outer claw with two ventral teeth, one small dorsal tooth, and basal comb smaller than basal comb of inner claw. Metatarsal claw: equal claws, two small lateral teeth, two dorsal teeth, and basal comb without elongate teeth. Wing ( Fig. 5E ) (n = 3; length: 2.5 mm; width: 1 mm) with membrane hyaline. Wing veins light brown and setose. Vein Sc ends basal or near to Rs origin. Vein R 2+3 curved, branched and with the origin basal or near to crossvein r-m origin. Vein M 1+2 bifurcated, M bifurcation ends near to R 2+3 branch origin. Crossvein m-m weak and basal to the crossvein r-m terminus. False vein distinct and parallel to CuA, reaching ca. the basal 1/3 of CuA. Vein CuP ends apical relative to Rs origin. Length ratios R 2+3 /R 3, M 1+2 /M 2 = 0.55, and 1.50, respectively. Halter yellow. Abdomen uniformly yellow. Terminalia ( Fig. 6A–C ) uniformly light brown. Tergite IX with pronounced convex posterior margin with scattered elongate setae. Sternite IX with posterior margin with concave area, lateral margin with three elongate setae, and posterolateral portion with a small process curved. Tergite X wider than long, with distinct lateral projection extending from the middle portion of the central plate to the anterior portion, membranous central plate with anterior portion more sclerotized and projected medially (not fused in the middle), and latero-medial portion with 5–6 short setae ( Fig. 5D ). Gonocoxite subcylindrical, wider than long, with gonocoxal apodeme elongated and its ventral portion with scattered setae ( Fig. 5G ). Apical gonocoxal lobe prominent with robust basal portion, 0.5x length of gonostylus (dorsal view), stem curved in the middle and one elongated seta in middle and basal portions, and apex curved with 2–3 small apical setae; basal gonocoxal lobe absent ( Fig. 5G ). Gonostylus cylindrical and subtly curved, setose, scattered sensilla on the external margin, 1–2 elongated setae in the subapical portion, and tapered apical portion with one stout seta ( Fig. 5G ). Parameres sinuous in dorsal view, anterior portion with a lateral projection with sharp apex (more easily seen in lateral view) ( Fig. 5E ). Aedeagus narrow, anterior portion bifurcated, posterior portion tapered with a small lateral projection ( Fig. 5F ).

Female and immatures. Unknown.

Distribution and bionomics. This species is only known from Brazil, Santa Catarina, Grão Pará (type locality) ( Fig. 10 ).

Remarks. Dixella jailtoi has a gonostylus similar to those of five species from Central America: Dixella maculata Chaverri & Borkent, 2007 , Dixella shannoni ( Lane, 1942) , Dixella fernandezae Chaverri & Borkent, 2007 , Dixella jironi Chaverri & Borkent, 2007 , Dixella woodi Chaverri & Borkent, 2007 ( Chaverri & Borkent 2007). These similar species typically have a more tapered gonostylus when compared to Dixella jailtoni . This new species is easily distinguished from these species by a unique light brown spot on the katepisternum ( Fig. 5D ), while D. maculata , D. fernandezae and D. woodi exhibit a uniform pattern (without spot), and D. jironi and D. shannoni have distinct bands.

Etymology. The specific epithet name is honor to Jailto Machado, grandfather of PLS.

Figures

FIGURE 5. Dixella jailtoi sp. nov., male: (A)—Habitus; (B)—Head and thorax, dorsal view; (C)—Antenna; (D)—Head and thorax, lateral view; (E)—Wing. Scale bar: (A) 0.7 mm, (B–C) 0.2 mm, (D–E) 0.3 mm.

FIGURE 6. Dixella jailtoi sp. nov., male terminalia: (A)—Dorsal view; (B)—Ventral view; (C)—Lateral view; (D)—Tergite X, dorsal view; (E)—Paramere, lateral view; (F)—Aedeagus, dorsal view; (G)—Gonocoxite and gonostylus, dorsal view. Scale bar: (A–C) 0.1 mm, (D) 0.05 mm, (E–G) 0.03 mm. Abbreviations: ap lob = apical gonocoxal lobe; gon ap = gonocoxal apodeme; goncx = gonocoxite; gonst = gonostylus.

FIGURE 10. Distribution map of Dixella species in Santa Catarina state, Brazil.