Phytobia dalensi Boucher 2025, n. sp.
Creators: name: Marc, Stéphanie Boucher
name: Pollet, Marc
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Agromyzidae
Phytobia
Phytobia dalensi

description: Phytobia dalensi Boucher, n. sp.
(Figs 14; 15)
urn:lsid:zoobank.org:act: 71404E3D-F260-4C95-BD87-57AF6FDEA619
TYPE MATERIAL. — Holotype. Guyane • ♂; Mitaraka, sampling site: MIT-E-savane roche 2; 02°13’59.8”N, 54°27’46.5”W; 471 m; open/ partially opened areas; 13-20.VIII.2015; MT (6 m); Pierre-Henri Dalens leg.; sample code: MITARAKA/230, sorted by M. Pollet; MNHN.
ETYMOLOGY. — The species name is a patronym in honour of Pierre-Henri Dalens, president of the Société entomologique Antilles-Guyane (SEAG) who participated to phases two and three of the expedition and collected most of the Agromyzidae of Mitaraka with a 6 m long Malaise trap on one of the savane roches.
DIAGNOSIS. — This species differs from all other Neotropical species of Phytobia by the combination of the following characters: wing hyaline; 3+ 0 dc with anterior postsutural dc strongly reduced; frons yellowish brown; anepisternum completely brown; mesonotum mostly black, with posterolateral corner narrowly yellow; femora yellow, with mid and hind femur narrowly brown apically; abdomen mostly yellow with black spots centrally and laterally on hind tergites; male distiphallus consisting of two tubules that are approximately 1.5 × length of mesophallus.
DISTRIBUTION. — French Guiana.
HOST. — Unknown.
DESCRIPTION
Male
Orbital plate not projecting in front of eye in profile; frons width including orbital plates 0.35 mm at midpoint; orbital plate 0.2 × width of frons at midpoint; lunule small, collapsed inside; ocellar triangle extended anteriorly to level of anterior ors; two reclinate ors and two ori: upper ori reclinate or lateroclinate and lower ori inclinate (Fig. 14B); orbital setulae reclinate, in one row, except for 1-2 extra setulae; first flagellomere small, rounded apically with short pubescence; arista long with distinct pubescence; gena narrow, at midpoint about 0.05 × maximum eye height (Fig. 14B); clypeus medium width, with upper margin rounded; small epistoma present (Fig. 14D); 3+ 0 dc with only two posterior ones well-developed (Fig. 14F), anterior postsutural dc reduced, about 0.33 × length of second dc; prsc present; acrostichal setulae numerous, in about 8-9 rows; mid tibia with two posterolateral setae; wing length approximately 2.2 mm (wing slightly bent); last section of M 4 0.6 × length of penultimate section; vein R 4+5 ending close to wing tip; distal margin of R 1 expanded near junction (Fig. 14E).
Colour
Frons mat, yellowish-brown (Fig. 14C); orbital plate and ocellar triangle subshining, darker brown except for orbital plate yellowish at level of ori and below; antennae yellowish, first flagellomere slightly infuscated with brown (Figs 14B, D); clypeus and palp yellowish brown; face yellowish (Fig. 14D); mesonotum shiny brown, with the posterolateral corner possibly narrowly yellow (difficult to see due to the collapsed thorax) (Fig. 14F); scutellum brown; postpronotum yellow with small brown spot; notopleuron yellow; other pleura completely brown; fore leg including coxa and trochanter yellow, tarsi slightly darker yellowish brown; mid and hind femora yellow with apex narrowly brown (Fig. 14A); mid coxa brownish; mid and hind tibia and tarsi brown; halter yellow; calypter and margin yellow; fringe brown. Abdomen yellow with dark brown spots medially on tergites 3-6 in addition to lateral brown spots on tergites 5-6 similar to P. corona Boucher, n. sp. (Fig. 12F).
Male genitalia
Distiphallus (Fig. 15B, arrow a) separated into two tubules (Fig. 15A) that are approximately 1.5 × longer than mesophallus (Fig. 15B, arrow b); hypandrium without distal apodeme, conspicuously constricted near midpoint (Fig. 15C); surstylus, typical of the Phytobia unica group (see above), with multiple spines (Fig. 15D); ejaculatory apodeme with short stalk and medium size blade (Fig. 15E).
REMARKS
This new species belongs to the Phytobia unica group (Boucher 2010) and is externally most similar to P. mentula Sasakawa, 1992 described from Peru (Sasakawa 1992a). The male phallus of these two species, however, is distinctly different. Phytobia dalensi Boucher, n. sp., was previously identified as morphospecies Phytobia Mit- 4 in Boucher & Pollet (2021).
description: Published as part of Marc, Stéphanie Boucher & Pollet, Marc, 2025, New species and new records of leaf-miner flies (Diptera, Agromyzidae) from rainforest and inselberg at Mitaraka (French Guiana), pp. 13-42 in Zoosystema 47 (2) on page 33, DOI: 10.5252/zoosystema2025v47a2, http://zenodo.org/record/14670952