Cloeodes xyrognathos Salles, Massariol & Angeli

Salles, F. F., Massariol, F. C., Angeli, K. B., Lima, M. M., Gattolliat, L. & Sartori, M., 2015, Revealing the diversity of Cloeodes Traver, 1938 (Ephemeroptera: Baetidae) in the Neotropics: description of eleven new species from Brazilian mountain ranges, Zootaxa 4020 (1), pp. 1-50 : 40-46

Cloeodes xyrognathos Salles, Massariol & Angeli , sp. nov.

Figures 3 d, 5c, 5d, 27, 28, 29, 30.

Diagnoses. NYMPH. A) Large body size (> 7.0 mm); B) Body color pattern with distinct darker marks on abdominal terga ( Fig. 3 d); C) Labrum, medially, with many setae ( Fig. 27 a); D) Incisors blade-like ( Figs. 27 b, 27c); E) Maxillary palp as long as length of galea-lacinia ( Fig. 27 d); F) Inner margin of labial palp segment III subequal to outer margin ( Fig. 27 e); G) Distal projection of fore femur short (not exceeding apex of femur, Figs. 28 a, 28b); H) Gills with medial rib ( Fig. 28 e). MALE IMAGO. A) Intercalary veins on fore wing approximately 0.6, 0.9 × the width of corresponding space ( Fig. 29 a); B) Hind wing present, with three longitudinal veins ( Figs. 29 b, 29c); C) Terga yellowish washed heavily with brown ( Fig. 5 c).

Nymph. Lengths. Body: 8.0– 8.5 mm; cerci: 4–4.5 mm; terminal filament: 3.0 mm.

Coloration ( Fig. 3 d). General coloration yellowish-white washed with brown to dark brown. Head with frons with area between antennal sockets yellowish. Thorax yellowish-brown with brownish marks. Fore leg, outer margin of femur and tibia washed with brown; tarsus profusely washed with brown. Abdomen with one lighter medial longitudinal stripe; segments I, II, VI and X profusely washed with brown; sterna yellowish white. Caudal filaments yellowish-brown with apex brown. Males lighter than female.

Head. Labrum ( Fig. 27 a). Trapezoidal; length about 0.5 × maximum width; dorsal arc with 18 continuous long setae; ventrally with 12–14 spine-like setae near lateral margin.

Mandibles ( Figs. 27 b, 27c). Margin between prostheca and mola with short spine-like setae. Incisors bladelike; denticles of mola constricted at base (as in fig. 6f).

Maxilla ( Fig. 27 d). Medially with 1 spine-like seta + 8 apically pointed setae. Maxillary palp reaching apex of galea-lacinia; palp segment II 1.1 × length of segment I.

Labium ( Fig. 27 e). Base of glossa expanded (reaching at least half of paraglossa); inner and outer margin respectively with around 20 and 12 spine-like setae increasing in length apically; ventral surface scattered with few short setae at base. Paraglossa dorsally with arc of 3 setae close to inner margin; ventrally with arc of 8–10 setae close to inner margin. Labial palp with segment I 1.2 × length of segments II and III combined; segment II dorsally with oblique row of 8 setae; segment III with distal margin slightly truncate; inner margin subequal to outer margin; ventrally covered with around 45 long setae ( Fig. 27 e); setae on inner margin serrate.

Thorax. Hind wing pad. Present.

Fore leg ( Fig. 28 a). Ratio 1.5:1(1.0 mm): 0.9: 0.2. Femur. Length about 4.2 × maximum width; outer margin with row of 14–17 clavate setae (length of setae about 0.09 × maximum width of femur); submarginal setae absent; anterior surface and inner margin with around 30 spine-like setae; posterior surface with around 20 scattered serrated setae near inner margin; distal projection short, not exceeding apex of femur ( Fig. 28 b), apically with 4 clavate setae. Tibia. Outer margin with few simple setae; inner margin with two serrate setae on apex; subtending bristle clavate, serrated, extending apex of tibia ( Fig. 28 c). Tarsus. Inner margin with row of 27+1 spine-like setae. Tarsal claw. 0.2 × length of tarsus.

Mid and hind legs. Similar to fore leg, except for the lower number of setae on anterior surface of femur and type of setae on inner apex of tibia (simple instead of serrate).

Abdomen. Terga ( Fig. 28 d). With spines present on posterior margin of segments III–X; larger spines on posterior margin 2.0 × longer than wide.

Sterna . With spines present on posterior margin of segments IV–IX.

Gills ( Fig. 28 e). Outer margin serrated on distal 1/4; inner margin slightly serrated; medial rib present (weak); tracheae extending from main trunk to inner and outer margins. Gill I subequal in length to segment II, oval. Gill IV little longer than length of segments V and VI combined, asymmetric, broad at middle. Gill VII little longer than length of segment VIII.

Paraproct ( Fig. 28 f). With around 18 spines.

Cercus . Without large spines.

Terminal filament. Without large spines.

Male imago. Lengths. Body: 7.6 mm; fore wing: 8.3 mm; hind wing: 1.3 mm; tibia I: 2.6 mm; tibia II: 1.4 mm; tibia III: 1.3 mm; caudal filaments: broken.

Coloration ( Fig. 5 c). Head yellowish washed with brown. Turbinate portion of compound eyes orange dorsally, stalk dark orange ( Fig. 5 c). Antenna translucent brown. Pro, meso and metanotum dark brown except for scutellum, lighter. Leg I: yellowish, femur with subapical orange band. Fore wing hyaline. Longitudinal and cross veins brown. Hind wing hyaline, veins light brown. Terga. Yellowish washed heavily with brown. Segment I dark brown. Segment II −VIII with dark brown marks medially and posterolaterally. Segments IX −X brown. Sterna . Yellowish washed brown, darker on lateral margins and with unpigmented area around sigilla. Forceps brown, lighter toward apex.

Head. Dorsal portion of turbinate eyes oblong; length 1.6 × width; stalk height 0.5 × width of dorsal portion; inner margins parallel, close to each other.

Thorax. Anteronotal protuberance rounded.

Metascutellar protuberance poorly developed, almost imperceptible.

Legs. Leg I: tibia 1.4 × length of femur; tarsi 1.4 × length of femur. Legs II and III: tibia 0.9 × length of femur; tarsi 0.5 × length of femur.

Fore wing ( Fig. 29 a) with stigmatic area with 6 cross veins touching Sc and 2 veins not touching Sc. Marginal intercalaries paired, except between veins R1-R2 and ICu1-ICu2 and ICu2-CuP, single and between veins Sc-R1 and CuP-A absent; length of each intercalary vein 0.9 and 0.6 × distance between adjacent longitudinal veins; length of fore wing about 2.5 × width.

Hind wing ( Figs. 29 b, 29c) present, with 3 complete longitudinal veins; costal process hooked, broad, located on basal third.

Abdomen. Genitalia ( Fig. 29 d). Forceps segment I sub-rectangular; 0.5 × length of segment II; wider than segment II, margins parallel. Forceps segment III oval, 1.5 × as long as wide; 0.2 × length of segments I and II combined. Posterior margin of subgenital plate rounded.

Female imago. Lengths. Body: 7.0 mm; fore wing: broken; hind wing: broken; tibia II: 1.2 mm; tibia III: 1.3 mm; caudal filaments: broken.

Coloration ( Fig. 5 d). Similar to male imago, except for: lighter general coloration; presence of a longitudinal brownish stripe on mesoscutum; wing membrane translucent brown, cross veins darker.

Leg II: tibia 0.8 × length of femur; tarsi 0.5 × length of femur. Leg III: tibia 0.9 × length of femur; tarsi 0.5 × length of femur.

Fore wing with stigmatic area with 6 cross veins touching Sc and 2 veins not touching Sc. Marginal intercalaries paired, except between veins ICu1-ICu2 single and between veins Sc-R1 and ICu2-A absent; intercalating one long/one short, one short/one long; length of each intercalary vein 1.0 and 0.6 × distance between adjacent longitudinal veins.

Hind wing present; with 3 complete longitudinal veins; costal process hooked, located on basal third.

Etymology. From the Greek words xyro, blade-like, and gnatho, jaw. An allusion to the shape of mandibular incisors.

Distribution ( Fig. 30 ). Southern Brazil, Santa Catarina State, Serra Geral.

Ontogenetic stage association. Rearing.

Type-material. HOLOTYPE. Male imago (with corresponding nymphal exuvia), wings and exuvia on two slides, one with dissected exuvia, one with wings, BRAZIL, Santa Catarina, Urubici, Cachoeira Véu de noiva, Perto do Morro da Aeronáutica, S 28°04’34.5” W 49°31’06.9”, 1346 m.a.s.l., 02/x/2011, Boldrini R, col. (CZNC). PARATYPES. 25 nymphs (one on slide), female imago with corresponding wings and nymphal exuvia (on slides) and male imago with corresponding nymphal exuvia, same data as holotype (10 CZNC, 10 INPA, 5 MZL).

Figures

FIGURE 3. Habitus, nymphs. a. Cloeodes melanotarsus (d. v.). b. Cloeodes melanotarsus (v. v.). c. Cloeodes tracheatus. d. Cloeodes xyrognathos.

FIGURE 5. Habitus, imagos. a. Cloeodes amantykyra, male (l. v.). b. Cloeodes amantykyra, male, head (d. v.). c. Cloeodes xyrognathos, male (d. v.). d. Cloeodes xyrognathos, female (d. v.).

FIGURE 27. Cloeodes xyrognathos, nymph. a. Labrum (d. v.). b. Right mandible (d. v.). c. Left mandible (d. v.). d. Maxilla (v. v.). e. Labium (v. v.).

FIGURE 28. Cloeodes xyrognathos, nymph. a. Fore leg, anterior surface. b. Fore femur, apex projection. c. Apex of fore tibia. d. Posterior margin of segment IV. e. Gill IV. f. Paraproct (v. v.).

FIGURE 29. Cloeodes xyrognathos, male imago. a. Fore wing. b. Hind wing. d. Hind wing, enlarged. d. Genitalia.

FIGURE 30. Political map of South America (showing Brazilian states) with details of the distribution of the new species of Cloeodes according to the altitude (white, from 0 to 400 m. a. s. l.; light gray from 400 to 800 m. a. s. l.; dark gray from 800 to 1200 m. a. s. l.; and black, above 1200 m. a. s. l.).