Leptoconops (Megaconops) floridensis Wirth

Santarém, Maria Clara Alves, Cremer, Marta Jussara, Vieira, Jenyffer Vierheller, Lemos, Giulia Gaglianone, Pecor, David B. & Felippe-Bauer, Maria Luiza, 2023, Redescription of Leptoconops (Leptoconops) brasiliensis (Lutz) and Leptoconops (Megaconops) floridensis Wirth (Diptera: Ceratopogonidae) with its first Brazilian record, Zootaxa 5380 (2), pp. 173-183 : 177-181

Leptoconops (Megaconops) floridensis Wirth

( Figures 3–6 )

Leptoconops (Leptoconops) floridensis Wirth, 1951: 281 (female; USA —Florida); Cavalieri & Chiossone, 1966: 56 (in key to American species).

Leptoconops (Megaconops) floridensis Wirth & Atchley, 1973: 18 (new combination; redescr. female, male; Colombia, Jamaica record); Ronderos & Spinelli, 1992: 43 (in key to Neotropical species); Borkent & Spinelli, 2000: 9 (in Catalog; distrib.); Borkent & Spinelli, 2007: 44 (in neotropical catalog); Borkent & Dominiak, 2020: 39 (in World Catalog); Spinelli et al., 2022: 488 (in key to Neotropical species).

Diagnosis. The only species of Leptoconops with the following combination of characters: antennal flagellomere 12 tapered distally, mandible without teeth, foretarsomere 3–4 with one dorsal subapical spine and spermathecae with ventral perforations, which is the diagnostic features of the subgenus L. ( Megaconops ).

Redescription. Female. Habitus as in Fig. 3 . Head ( Fig. 4A ). Dark brown. Eyes ( Figs. 4A–B ) bare, separated by a distance equal to 0.21–0.25 (0.23, n=17) of total head width, separation approximately to diameter of 7–9 ommatidial facets; vertex with 5–7 pairs of long setae, frons ( Figs. 4B , 6A ) with 2–9 mesal setae, usually distributed unequally on each side, clypeus ( Fig. 4C ) with two long mesal setae, 1–6 anterior small setae, 2–4 lateral small setae unequally distributed. Antenna ( Fig. 4A ) with pale scape, pedicel and flagellum dark brown with 12 flagellomeres, lengths of flagellomeres in proportion of 55-30-28-28-28-28-28-28-28-28-30-100 μm; last flagellomere 2.20–3.50 (2.8, n=16) longer than broad, tapered, slender distally; AR 0.63–0.81 (0.73, n=17). Palpus ( Fig. 4D ) dark brown; 1 st and 2 nd segment indistinctly separated; lengths of segments in proportion of 68 (I+II)-92-51 μm; 3 rd segment elongated, slightly swollen, with dense sensilla clustered internally for most of its length; PR 2.5–4.0 (3.5, n=17). Mandible without teeth, P/H ratio 0.58–0.69 (0.63, n=15).

Thorax. Dark brown, scutum clothed with setae, paler medially; humeral depressions with three round sensory areas in a row; prescutellar area with 1–2 median pair of tubercles; scutellum convex, paler medially, with fine long marginal hairs. Legs ( Fig. 5C ) uniformly dark brown, tibiae paler on narrow apices; tarsi ( Fig. 5D ) brown; hind tibial comb with 3 (n=17) spines; first to third from the spur measuring 57.5–72 (66, n=17) μm, 50–65 (56, n=17) μm, 25–43 (36, n=17) μm. Basitarsi with ventral spines, 5–10 on fore, 4–7 on median, 9–12 on posterior; one ventral apical spine on tarsomeres 1–4; one dorsal sub-apical spine on fore tarsomeres 3–4 ( Fig. 5D ); tarsal claws short, slightly curved, without basal spines or bristles, 0.45–0.50 (0.46, n=17) as long as 5 th tarsomeres. Wing ( Figs. 5A–B ) membrane infuscated, microtrichia abundant, stigma pale brown; longitudinal veins reaching wing margin; wing length 1.15–1.32 (1.26, n=17) mm, width 0.55–0.65 (0.61, n=17) mm; costa extending to 0.38–0.41 (0.39, n=17) of total wing length. Halter dark brown.

Abdomen. Brown. Genital lamellae ( Fig. 5E ) brown, long, narrow, about 3.15–4.69 (3.73, n=17) longer than broad, 2.5–4.0 (3.3, n=17) longer than 9 th sternite. Sternite 8 ( Fig. 5F ) with deep caudomedian excavation, the margin bearing dense fine hairs and two longer hairs laterally; sternite 9 ( Figs. 5G , 6B ) with deep, subrectangular excavation which distinct gonopore. Spermathecae ( Fig. 5G ) two, ovoid, subequal, measuring 52.5–42.5 (48.2, n=17) by 47.5–35 (39.6, n=17) μm and 50–37.5 (44.5, n=17) by 45–32.5 (36.5, n=17) μm, with ventral hyaline perforations; sclerotized necks with 5–7 (6, n=13) μm.

Male. See Wirth & Atchley (1973).

Material examined. Holotype female, slide mounted, labeled “ Santa Rosa Island , Escambia Co., Florida, UNITED STATES, 7 June 1949, light trap ( USNMENT01239517 ); 234 females “ São Francisco do Sul , Santa Catarina, BRAZIL, biting birds, equipe PMP-BS col.(NEW RECORD): “ Baía Babitonga , 31.I.2021 ”, 3 females [1 slide mounted ( CCER#3849 ); 2 in glycerol ( CCER#3858 )]; “ Capri , 20.XII.2020, 47 females [1 slide mounted ( CCER#3845 ), 46 in glycerol ( CCER#3861 )], “ 28.I.2021 ”, 11 females [2 slide mounted ( CCER#3838-3839 ), 9 in glycerol ( CCER#3857 )], “ 14.XII.2021 ”, 4 females [1 slide mounted ( CCER#3848 ), 3 in glycerol ( CCER#3866 )], “ 12.II.2022 ”, 2 females [in glycerol ( CCER#3870 )], “ 13.II.2022 ”, 7 females [in glycerol ( CCER#3871 )], “ 25. II.2022 ”, 3 females [in glycerol ( CCER#3872 )], “ 03.III.2022 ”, 3 females [in glycerol ( CCER#3873 )]; “ Enseada , 01.I.2021 ”, 2 females [1 slide mounted ( CCER#3850 ), 1 in glycerol ( CCER#3863 )], “ 04.II.2021 ”, 1 female [slide mounted ( CCER#3836 )], “ 28.XII.2021 ”, 7 females [1 slide mounted ( CCER#3847 ), 6 in glycerol ( CCER#3865 )], “ 20.XII.2022 ”, 4 females [in glycerol ( CCER#3875 )]; “ Ervino , “ 23.I.2023 ”, 2 females [in glycerol ( CCER#3877 )]; “ Forte , 27.XII.2020 ”, 9 females [2 slide mounted ( CCER#3843-3844 ), 7 in glycerol ( CCER#3862 )], “ 12.XII.2022 ”, 3 females [in glycerol ( CCER#3874 )], “ 29.XII.2022 ”, 119 females [2 slide mounted ( CCER#3851-3852 ), 117 in glycerol ( CCER#3876 )]; Praia Grande, “ 02.XII.2021 ”, 1 female [in glycerol ( CCER#3868 )]; “ Prainha , 20.I.2022 ”, 1 female [in glycerol ( CCER#3869 )]; “ Rio Monte de Trigo , 06.II.2021 ”, 1female [slide mounted ( CCER#3837 )]; “ Ubatuba , 06.I.2021 ”, 1 female [in glycerol ( CCER#3864 )], “ 14.XII.2021 ”, 3 females [1 slide mounted ( CCER#3840 ), 2 in glycerol ( CCER#3867 )]; 10 females “Itapoá, Santa Catarina, BRAZIL, biting birds, equipe PMP-BS col.” ( NEW RECORD): “ Pontal , 04.II.2021 ”, 9 females [2 slide mounted ( CCER#3841-3842 ), 7 in glycerol ( CCER#3859- 3860 )]; “ Barra do Saí , 26.XII.2021 ”, 1 female [slide mounted ( CCER#3846 )].

Distribution. United States (Florida), Jamaica (?), Colombia, Brazil (Santa Catarina).

Taxonomic discussion. Leptoconops (Megaconops) floridensis Wirth is the unique species described for this subgenus worldwide. Wirth & Atchley (1973) described L. ( Megaconops ) based on this species and remarked that it is similar to Leptoconops (sensu stricto), but females differ in the leg and antennal proportions, claw structure and setation of the frons. In fact, we observe that in L. (M.) floridensis femora and tibiae legs are stout, the flagellomere 12 is tapered and slender distally, and the tarsal claws lack basal spines or bristles, while in the Leptoconops subgenus the femora and tibiae are slender, the flagellomere 12 is usually blunt or conical and the claws present a basal bristle. However, the frons setation is too variable in our L. (M.) floridensis specimens and we cannot differ it from other species within the L. ( Leptoconops ). Wirth & Atchley (1973), in their redescription, indicated that frons present four to five pairs of fine setae, despite the drawing show four setae on left and five on right side. In really, we can see the drawing pattern in the holotype specimen ( Fig. 4B ), with a total of nine mesal setae. Here, we analyze more specimens, and we can see that the unequal distribution on each side is usual, with the frons presenting 2–9 mesal setae ( Fig. 6A ). In the description of L. (M.) floridensis ( Wirth 1951) and in its subsequent redescription ( Wirth & Atchley 1973), the authors state that the tarsomeres are unarmed. In contrast, we observe that the tarsomeres present spines, primarily the basitarsi, but they are more hyaline and slenderer than commonly seen in other species from the genus. Also, we can see a strong subapical dorsal spine in the fore tarsomeres 3 and 4, which is a unique characteristic of this species. Considering this, we suggest that frons setation is not a good feature to identify L. (M.) floridensis and consequently the subgenus Megaconops . In addition, the mandible lacking any teeth, the fore tarsomeres 3–4 with a dorsal subapical spine and the spermathecae with ventral perforations are unusual characteristics and unique within all Leptoconops species and can be more accurate to identify this species.

Leptoconops (M.) floridensis was described by Wirth (1951) to Santa Rosa Island, Escambia County, Florida, United States. Posteriorly Wirth & Atchley (1973) found it in Seahorse key, Levy County, and in a mangrove area in Colombia, in both places they were biting humans. The authors also describe a single male specimen from Jamaica which they presumed on general characters of size, coloration, and close similarity in external features to be L. (M.) floridensis , but they emphasize that additional collecting was necessary to prove it. Considering this, we maintain the record for Jamaica with a question mark.

Herein, we found the species in the estuary and on sandy beaches, also a coastal area, in Santa Catarina, Brazil, biting birds. It is the first record of this subgenus in Brazil. As any male specimens were found, we did not add any characteristic to its first description made by Wirth & Atchley (1973).

Figures

FIGURE 3. Adult female specimens of Leptoconops (Megaconops) floridensis Wirth from Santa Catarina (Brazil), dorsal and lateral view.

FIGURE 4. Leptoconops (Megaconops) floridensis Wirth, female. A. head, anterior view, B. frons setae, anterior view; C. clypeus setae, anterior view; D. third palpal segments, lateral view; ventral view in detail. Figures B, D from type specimen, other figures from additional material from Santa Catarina (Brazil).

FIGURE 5. Leptoconops (Megaconops) floridensis Wirth, female. A. wing; B. wing in phase contrast microscopy; C. fore-, mid-, hind legs (left to right), lateral view; D. fore-, mid-, hind tarsomeres (bottom to top); dorsal spines from tarsomeres 3 and 4 in detail; E. apex of abdomen, ventral view; F. Sternite 8, ventral view; G. Spermathecae and sternite 9, ventral view. Figures from additional material from Santa Catarina (Brazil).

FIGURE 6. Leptoconops (Megaconops) floridensis Wirth, female. A. Frons setation drawing from different specimens; B. Drawing from apex of abdomen showing the sternite 9 excavation and spermatheca.