Oukuriella froehlichi, Fusari, Lívia Maria, Bellodi, Carolina Ferraz & Lamas, Carlos José Einicker, 2014

Fusari, Lívia Maria, Bellodi, Carolina Ferraz & Lamas, Carlos José Einicker, 2014, A new species of sponge-dwelling Oukuriella (Chironomidae) from Brazil, Zootaxa 3764 (4), pp. 418-426 : 419-421

Oukuriella froehlichi sp. n.

Type material: Holotype male, BRAZIL, São Paulo, Salesópolis, Estação Biológica de Boracéia, 23°31’55”S 45°50’45”W, 10.x.2007, adult male, light trap, leg. Froehlich, C. G. ( MZUSP). Paratypes: 2 males, with the same data as holotype ( MZUSP).

Etymology. The species is in honour of Dr. Claudio Gilberto Froehlich (FFCLRP-USP), who dedicated his life to Science and also collected all type-series.

Diagnosis. Oukuriella froehlichi sp. n. differs from other congeneric species by: male, wings with dark macula, thorax lacking scutal tubercle, legs light brown with dark brown spot, tergites II–VII with tufts of setae, lateral projections on the posterior margin of tergite IX absent, concavity width equivalent to its depth, and posterior margin of tergite IX with tufts of setae, seen in ventral view. O. froehlichi sp. n. closely resembles O. baiana Fusari, Roque et Hamada, 2013 , from which it can be distinguished by the shape of the superior volsella, and tufts of setae in the ventral margin of tergite IX.

Description. Male (n= 2–3)

Color: Thorax light brown with dark brown areas ( Fig. 1 B). Wings with dark markings, veins light brown ( Fig. 1 C). Legs light brown with dark brown rings ( Fig. 1 D). Abdomen light brown, except for third tergite, dark brown; anterior transversal band of fourth tergite dark brown ( Fig. 1 E).

Total length 2.94–3.52 mm. Wing length 2.22–2.59 mm, width 0.69–0.81 mm. Total length/wing length 1.30– 1.40. Wing length/profemur length ratio 1.5.

Head. ( Fig. 1 A) AR 0.97–1.00. Apical flagellomere 625–735 µm long. Temporals 6. Clypeus with 34–56 setae. Lengths of palpomeres 1–5 (in µm): 35–38; 37–40; 188–195; 154–162; 185–189.

Thorax. ( Fig. 1 B) Without scutal tubercle. Ac 5–10; Dc 7–14; Scts 9–13.

Wing. ( Fig. 1 C) VR 1.25–1.30. Brachiolum with 2–3 setae. R with 8–10, R1 with 16–24, R4+5 with 25–32 setae, remaining veins and cell membranes bare.

Legs. ( Fig. 1 D) Lengths (in µm) and proportions of leg segments as in Table 1 . Tibial spur lengths (in µm): fore 57–60, middle 79–85, hind 92–96.

Abdomen ( Fig. 1 E). Tergites II–VII with large tuft of setae in anterior median region, and pair of small tufts of setae on latero-median region.

Hypopygium. ( Figs. 1 F, 2 A–C) Laterosternite IX with 6–7 setae. Posterior margin of tergite IX without projections. Concavity of posterior margin of tergite IX as wide as deep. Margin of tergite in ventral view with tufts of setae ( Fig. 2 B). Phallapodeme 53–65 µm long, transverse sternapodeme 36–57 µm. Superior volsella falciform 101–110 µm long, with 11 setae. Digitus long, lacking microtrichae, with same shape of superior volsella, 104–114 µm long. Inferior volsella 150–159 µm long, with 2 basal setae, 2–4 dorsal setae and 13–15 apical setae. Gonocoxite 175–192 µm long. Gonostylus with 211–233 µm long. HR 0.82–0.83. HV 1.40–1.51.

Female and immatures. Unknown.

Phylogenetic analysis. The analyses lead to two equally parsimonious cladograms with 228 steps, consistency index (CI) of 0.38 and retention index (RI) of 0.53. Both topologies ( Figs. 3 A–B) show O. froehlichi sp. n. placed within the clade recognized as inhabitants of freshwater sponges. It was recovered as sister group of O. baiana ; (( O. baiana + O. froehlichi ) O. rimamplusa )).

In the phylogeny inferred by Fusari et al. (2013), the sponge-dwelling representatives of Oukuriella were recovered as a monophyletic clade, supported by morphological features of adult males such as presence of tufts of setae on tergites; all legs pigmented; and volsella inferior with plumose setae.

Unlike cladograms obtained in Fusari et al. (2013), there was a fluctuation in the position of O. albistyla ( Fig. 3 B) that grouped with the saproxylophilic species.

Figures

FIGURE 1. Oukuriella froehlichi sp. n., male. A – Head, B – Thorax, C – Wing, D – Legs, E – Abdomen, F – Hypopygium.

FIGURE 2. Oukuriella froehlichi sp. n., male. A – Dorsal aspect of hypopygium with gonocoxite and gonostylus on the left; B – Detail of margin of tergite IX in ventral view; C – hypopygium with tergite IX removed, left dorsal view, ventral right view.

FIGURE 3. Two cladograms obtained after implied weighting of characters, delimiting clades with supposed larval habitats. “ * ” assigns species with known larvae.

Tables

TABLE 1. Lengths (in µm) and proportions of legs of Oukuriella froehlichi sp. n., male (n = 2 – 3).

Fe	Ti	ta1	ta2	ta3
P1 1508–1737	925–1064	1535–1828	948–1109	700–762
P2 1497–1750	926–1159	714–832	362–442	245–273
P3 1558–1813	898–1059	901–1065	535–618	365–424
continued.
ta4	ta5	LR	BV	SV
P1 497–596	237–280	1.66–1.72	1.67–1.69	1.53–1.59
P2 135–156	121–122	0.72–0.77	3.63–3.77	3.39–3.50
P3 201–213	118–126	1.00–1.01	2.74–2.87	2.70–2.73