Dasineura microstachysae Carvalho-Fernandes & Maia, 2025

Carvalho-Fernandes, Valéria Cid Maia and Sheila Patrícia, 2025, Two new species of Dasineura (Diptera: Cecidomyiidae) from the Neotropics and new morphological data on Dasineura tavaresi, Zoologia (e 24033) 42, pp. 1-16 : 7-12

Dasineura microstachysae Carvalho-Fernandes & Maia , sp. nov.

Figs 4–6

https://zoobank.org/ 79B5A987-8756-4FD8-BA74-84976D924AD1

Diagnosis. Male with 15 flagellomeres, female with 14–15 flagellomeres and 8 th tergite longitudinally divided; pupa with dorsal spines on the second to eighth abdominal segments; larval spatula without prominent teeth.

Male ( Figs 4A – 6A ): Body: 2.20–2.50 mm long. Head globoid, 0.30–0.32 mm long, 0.30–0.32 mm wide; eye facets circular, closely appressed, except laterally and at vertex; antenna ( Fig. 4A): scape wider apically than basally, 0.05–0.06 mm long, 0.06–0.07 mm wide, pedicel globoid, 0.04–0.05 mm long, 0.05 mm wide, 15 flagellomeres, 1 st and 2 nd flagellomeres fused, 0.18–0.19 mm long, 3rd–9 th flagellomeres 0.10 mm long, 10 th –15 th progressively shorter, 10 th and 11 th flagellomeres 0.09–0.10 mm long, 12 th and 13 th flagellomeres 0.07–0.09 mm long, 14 th flagellomere 0.07–0.08 mm long, 15 th flagellomere 0.06–0.07 mm long, 2 nd –14 th flagellomeres each consisting of node and neck, nodes cylindrical, setulose, necks elongate, bare, 15 th flagellomere conical, with apical process in two specimens; circumfila composed of two horizontal rings connected by two longitudinal bands ( Fig. 4B), proportion node/neck: 2/1, last flagellomere with short apical process; mouth parts: labrum long-attenuate, with three pairs of setae; hypopharynx of the same shape of labrum, with long lateral setulae anteriorly directed, 0.09–0.11 mm long; palpus four-segmented, 1 st segment globoid or cilindrical, shorter than others, 0.03 mm long, 2 nd 3 rd and 4 th segments cylindrical and progressively longer, 2 nd segment 0.04–0.05 mm long, 3 rd segment 0.05–0.06 mm long, 4 th segment 0.05–0.07 mm long; labella pointed distally, 0.05–0.06 mm long, with lateral and mesal setae. Thorax: scutum with two dorsocentral rows of setae, lateral row of setae on each side, scales intermixed; scutellum with setae only in the basal half; anepimeron with a longitudinal row of setae and some scales, other pleura bare; wing 1.62–1.70 mm long, 0.75–0.85 mm wide, C with break at juncture with R 5, Rs reduced to bend on R 5, Cu forked ( Fig. 4C); tarsal claws one-toothed, curved beyond midlength, empodia about as long as claws ( Fig. 4D). Abdomen ( Fig. 4E): Sclerites with basal pair of trichoid sensillae; 1 st –6 th tergites rectangular with scattered scales, few lateral setae, posterior row of setae; 7 th –8 th tergites band-like, 7 th tergite with few lateral, pair of trichoid sensillae and no caudal setae, 8 th tergite with only trichoid sensillae as vestiture; 2 nd –6 th sternites rectangular, with scattered scales, mesal and posterior row of setae, few lateral setae, 7 th and 8 th sternites with setae of posterior row more abundant than in the others sternites, few lateral setae. Male terminalia ( Figs 4F, 5A): gonocoxite cylindrical, setose and setulose; gonostylus claviform, larger basally and tapering towards apex, setulose in the basal half, striated in the distal half, with scattered short setae, and apical claw; cerci entirely setulose, lobes wide, rounded, with several apical setae; hypoproct entirely setulose, bilobed, lobes slender, acute, incision straight between them, two setae on each lobe; parameres slightly shorter than aedeagus, entirely setulose, with setose papillae on each lobe apically; aedeagus cylindrical, slightly truncate at apex.

Female ( Fig. 5B–E): Body: 2.20–2.50 mm long. Head globoid, 0.32–0.35 mm long, 0.32–0.36 mm wide; antennae ( Fig. 5B) with 14–15 flagellomeres progressively shorter, flagellomeres setulose, with very short necks (in two specimens last flagellomere longer than the preceding one), scape trapezoid, 0.04–0.06 mm long, 0.05–0.065 mm wide, pedicel globoid, 0.04–0.05 mm long, 0.05–0.055 mm wide, 1 st and 2 nd flagellomeres fused, 0.14–0.15 mm long, 3 rd and 4 th flagellomeres 0.06–0.07 mm long, 5 th –9 th flagellomeres 0.06–0.065 mm long, 10 th and 11 th flagellomeres 0.06 mm long, 12 th flagellomere 0.05–0.06 mm long, 13 th –14 th flagellomeres 0.045–0.07 mm long, 15 th flagellomere 0.04–0.05 mm long; circumfila as in Fig. 5C, mouth parts: hypopharynx 0.09–0.10 mm; palpus: 1 st segment 0.03–0.05 mm long, 2 nd segment 0.03–0.06 mm long, as long or longer than 1 st segment, 3 rd segment 0.04–0.06 mm long, as long or longer than 2 nd segment, 4 th segment 0.07–0.09 mm long and thinner than the others; labella 0.05–0.07 mm long. Thorax: wing 1.30–1.60 mm long, 0.60–0.65 mm wide. Abdomen ( Fig. 5D): sclerites with basal pair of trichoid sensillae; 1 st –6 th tergites rectangular with scattered scales, posterior row of setae, 7 st tergite X-shaped with scattered scales, posterior row of setae, setae more abundant than on the preceding tergites, 8 th tergite divided into two longitudinal sclerites, with only trichoid sensillae as vestiture ( Fig. 5E); 2 nd –7 th sternites rectangular, with mesal band and posterior row of setae, few lateral setae, 8 th sternite not developed. Ovipositor ( Fig. 5E) long, protractile; cerci large, fused, entirely setulose, with thick sensory hairs apically; hypoproct small, delicate, bilobed in ventral view, with pair of setae apically.

Pupa ( Figs 5F – 6B ): Body ( Fig. 5F): 2.20–2.55 mm long. Head ( Fig. 6A ): apical seta 0.15–0.17 mm long, antennal horns absent, frons of each side with two frontal and three lateral papillae, one of each set setose, remaining asetose. Thorax: Integument smooth, prothoracic spiracle well developed, strongly sclerotized, conical, 0.13–0.16 mm long, with trachea ending at apex ( Fig. 6B ). Abdomen: Segments 2–8 with transverse rows of dorsal spines restricted to the central area of the basal third ( Fig. 5G).

Larva of 3 rd instar ( Fig. 6C–E ): White, body: 1.75–2.40 mm long. Head ( Fig. 6C ): proportion head capsule/posterolateral apodemes: 2.5/1. Thorax: Prothoracic spatula 0.12–0.13 mm long, strongly sclerotized, anterior margin with no teeth ( Fig. 6D ) or microserrated in some specimens ( Fig. 6E ), stalk moderately developed, proportion between teeth and stalk two groups of three lateral papillae on each side, two with setae and one asetose in each group ( Fig. 6D ). Integument grainy ventrolaterally, ventral spiculae on the central area of each thoracic segment and 1 st to 7 th abdominal segments. Terminal segment with four pairs of papillae, all with setae of similar length.

Gall ( Fig. 6F ). Leaf marginal roll, green, glabrous. The gall is occupied by a single gall-inducing larva.

Material examined. Holotype ♂, Brazil, RJ, Arraial do Cabo , Parque Estadual da Costa do Sol , 01.VI.2012, S.P.C. Fernandes col. ( MNRJ-ENT1-70176 ); paratypes: same data, 2♂ (1♂, MNRJ-ENT1-70178 ; 1♂, MHNCE-ENT1-1997 ); 6♀ (1♀, MNRJ-ENT1-70186 ; 1♀, MNRJ-ENT1-70187 ; 1♀, MNRJ-ENT1-70188 ; 1♀, MNRJ-ENT1-70189 ; 1♀, MHNCE-ENT1-1998 ; 1♀, MHNCE-ENT1-1999 ), 4 pupal exuviae ( MNRJ-ENT1-70191 ); same locality, 08.VI.2021, S. Ascendino col., 3♂ (1♂, MHNCE-ENT1-1996 ; 1♂, MNRJ-ENT1-70177 ; 1♂, MNRJ-ENT1-70179 ); 2♀ (1♀, MNRJ-ENT1-70180 ; 1♀, MNRJ-ENT1-70181 ); 1 larva of 3 rd instar ( MNRJ-ENT1-70175 ); Carapebus, Parque Nacional da Restinga de Jurubatiba, 26.IX.1998, V. Maia col., 1 pupal exuvia ( MNRJ-ENT1-70183 ); 28.XI.1998, same collector, 9 larvae of 3 rd instar (5 larvae, MNRJ-ENT1-70185 ; 4 larvae, MNRJ-ENT1-70184 ); Maricá, APA de Maricá, 01.VII.2021, Maia & Gomes col., 2♀ (1♀, MNRJ-ENT1-70192 ; 1♀, MNRJ-ENT1-70193 ), 3 pupal exuviae (1 pupal exuvia, MNRJ-ENT1-70190 ; 2 pupal exuviae, MNRJ-ENT1-70195 ), 2 larvae of 3 rd instar ( MNRJ-ENT1-70194 ); same locality and collectors, 31.VII.2021, 4 pupal exuviae ( MHNCE-ENT1-1995 ); same locality, 30.VII.2019, V. Maia col., 1♂ ( MNRJ-ENT1-70182 ).

Additional material. Brazil, RJ, Arraial do Cabo , Parque Estadual da Costa do Sol, 01. VI.2012, S.P.C. Fernandes col., 2♂ (1♂, MNRJ-ENT1-69156 ; 1♂ MNRJ-ENT1-69160 ), 3♀ (1♀, MNRJ-ENT1-69157 ; 1♀, 1♀, MNRJ-ENT1-69158 ; 1♀, MNRJ-ENT1-69159 ) ; Maricá , APA de Maricá, 01.VII.2021, Maia & Gomes col., 3♀ (1♀, MNRJ-ENT1-70170 ; 1♀, MNRJ-ENT1-70171 ; 1♀, MNRJ-ENT1-70172 ) ; same locality and collectors, 25. V.2021, 2♂ ( MNRJ-ENT1-70167 , MNRJ- - ENT1-70168 ), 1 pupal exuvia ( MNRJ-ENT1-70169 ) ; same locality, Maia & Azevedo col., 18. VI.2002, 1 pupal exuvia and two wings ( MNRJ-ENT1-70166 ) ; Oliveira & Maia col., 11. V.2005, 1♀ ( MNRJ-ENT1-70165 ) ; 11. V.2005, V. Maia col., 1 pupal exuvia ( MNRJ-ENT1-70164 ) ; 08.VII.2004, V. Maia col., 1 pupa ( MNRJ-ENT1-70163 ) ; Maricá , Itaipuaçu, 10.VII.1998, V. Maia col., 2♂ (1♂, MNRJ-ENT1-70173 ; 1♂, MNRJ-ENT1-70174 ) .

Geographical distribution. Brazil, Rio de Janeiro, São João da Barra, Carapebus, Arraial do Cabo, Araruama, Saquarema, Maricá.

Etymology. The word “ microstachysae ” refers to the genus of the host plant.

C

Remarks. Dasineura capsicicola , sp. nov., D. microstachysae , sp. nov., D. couepiae , D. gigantea , and D. marginalis are the only species from Brazil with female 8 th tergite longitudinally divided. In the other species, the female 8 th tergite is entire. It is clear that the genus needs to be revised. Several species were described when the genus comprised all Oligotrophini species with four-segmented palpus, fused female cerci, toothed tarsal claws, and R 5 shorter than wing length. Thus, the current diagnostic combination of characters is not found in all described species. Furthermore, Oligotrophini are not more accepted as a tribe, and Dasineura has been placed in the tribe Dasineurini . Comparing the two new species of Dasineura to D. couepiae , D. gigantea and D. marginalis , we can realize that pupa of Dasineura capsicicola has the longest cephalic seta and prothoracic spiracle, and the larval spatula lacks lateral projection, while Dasineura microstachysae is unique in having prothoracic spatula with no prominent teeth. Furthermore, only pupae of both new species have abdominal dorsal spines.

Figures

Figure 6. Dasineura microstachysae sp. nov. (A,B) pupa: (A) head, ventral view, (B) prothoracic spiracle, (C–E) larva of third instar: (C) head, ventral view, (D–E) prothoracic spatula, ventral view, (D) spatula with smooth anterior margin and associated papillae, (E) spatula with microserrated anterior margin, (F) gall, general aspect.