Tricorythopsis similis, De Oliveira & Do Nascimento & Couceiro, 2021

De Oliveira, Laura A., Do Nascimento, Jeane M. C. & Couceiro, Sheyla R. M., 2021, A new species of Tricorythopsis Traver, 1958 (Ephemeroptera: Leptohyphidae) from Pará state, Brazil, Zootaxa 5023 (1), pp. 131-141 : 132-135

publication ID

https://doi.org/10.11646/zootaxa.5023.1.8

publication LSID

lsid:zoobank.org:pub:80DA6665-6702-41DC-8C14-1AED9266D46C

DOI

https://doi.org/10.5281/zenodo.5225585

persistent identifier

https://treatment.plazi.org/id/3123879E-FFBD-A559-FF16-955952E8F97D

treatment provided by

Plazi

scientific name

Tricorythopsis similis
status

sp. nov.

Tricorythopsis similis sp. nov.

( Figs 2–5 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 )

Diagnosis. Nymph: 1) maxillary palp 1-segmented ( Fig. 4E View FIGURE 4 ); 2) segment II of labial palpi shorter than segment I and longer than segment III ( Fig. 4F View FIGURE 4 ); 3) femora and tibiae with margins covered by long and pectinate setae ( Figs 5A–D View FIGURE 5 ); 4) tarsal claws with 4 to 5 marginal denticles and 4+2 very small, submarginal denticles ( Fig. 5E View FIGURE 5 ); 5) abdominal terga III–VII with acute, serrated tubercles medially located on posterior margins ( Figs 2A–C View FIGURE 2 , 3C View FIGURE 3 ); 6) transversal line of operculate gill absent ( Fig. 3D View FIGURE 3 ).

Mature nymph. Length: body, 2.3 mm; antenna, 0.7 mm; mesonotum, 0.8 mm; caudal filaments broken. Body robust, base of the abdomen wider than the apex ( Fig. 2A View FIGURE 2 ). General coloration yellowish brown, with blackish and purplish marks irregularly distributed. Head. Yellowish brown, with few, blackish marks irregularly distributed. Tubercles absent. Eyes and ocelli blackish ( Figs 2A–B View FIGURE 2 ; 3A View FIGURE 3 ). Antennae: scape and pedicel whitish yellow, flagellomeres grayish translucent on basal half and whitish translucent on distal half. Mouthparts yellowish translucent ( Figs 3B View FIGURE 3 ; 4A–G View FIGURE 4 ). Labrum broad, with shallow anteromedial emargination; with pores distributed on basal 1/4 ( Fig. 4A View FIGURE 4 ). Hypopharynx as in Figure 4B View FIGURE 4 . Mandible: basal half with purplish marks irregularly distributed; incisors and molars dark brown ( Figs 4C–D View FIGURE 4 ); basal 3/5 with spaced pores. Maxilla with pectinate setae at the apex; palp 1-segmented, approximately 2.5 times longer than wide, with a terminal seta ( Fig. 4E View FIGURE 4 ). Labium with spaced pores; glossa not fused, with filiform setae; paraglossa with filiform setae; segment II of labial palp shorter than segment I and longer than segment III ( Fig. 4F View FIGURE 4 ); lateral margin of submentum with short, filiform setae ( Fig. 4F View FIGURE 4 ). Thorax. Yellowish brown, with blackish marks irregularly distributed and with purplish marks near medial line ( Figs 2A–B View FIGURE 2 ; 3A View FIGURE 3 ). Pronotum without tubercles; anterolateral corner projected and rounded ( Fig. 3A View FIGURE 3 ). Mesonotum with a pair of small anterolateral tubercles; with a pair of slightly developed submedial humps near apex of forewing pads ( Fig. 3A View FIGURE 3 ). Developing wings with dark gray veins; internal margin blackish basally. Legs. General coloration yellowish white, with purplish and grayish marks; dorsal surface of femora with circular, whitish marks irregularly distributed ( Figs 5A–D View FIGURE 5 ). Coxae projections absent. Femora almost 1.5 times longer than wide. Femora and tibiae with margins covered by long and pectinate setae. Fore femur with a transversal row of long, pectinate setae on submedial region of the dorsal surface. Tarsal claws ( Fig. 5E View FIGURE 5 ) almost entirely yellowish white, except by apical region yellowish brown; with 4 to 5 marginal denticles and 4+2 very small, submarginal denticles; with apical seta. Abdomen. Terga yellowish brown, with blackish marks; segments VII–IX with a paired sublateral, transversal, blackish strip ( Figs 2A–C View FIGURE 2 ; 3C View FIGURE 3 ). Sterna whitish yellow. Segments III–IX with lateral margins expanded; segments VI–IX with posterolateral projections bordered with thin setae (projection less developed on segment VI) ( Figs 2C View FIGURE 2 ; 3C View FIGURE 3 ). Terga III–VII with acute, serrated tubercles medially located on posterior margins; tubercle slightly shorter on tergum III ( Figs 2A–C View FIGURE 2 ; 3C View FIGURE 3 ). Gills. Operculate gills yellowish brown, with purplish or grayish marks; oval, almost 1.4 times longer than wide; reaching the segment VII ( Figs 2A–C View FIGURE 2 ; 3C–D View FIGURE 3 ). Ventral lamellae without fringed lobes, without ridges. Transversal line of operculate gill absent. Caudal filaments yellowish brown, with short setae at segment joints.

Adults. Unknown

Etymology. The specific epithet is a Latin word meaning alike. It is in reference to the general similarity of this species and T. rondoniensis .

Habitat. Nymphs of Tricorythopsis similis sp. nov. were collected in two slow-flowing rivers (with width varying to 6–12 m) and associated to marginal vegetation in sections exposed to sunlight ( Figs 1D–E View FIGURE 1 ).

Material examined. HOLOTYPE. Mature nymph, Brazil, Pará state, Santarém, Ponte do Juá stream, 02°26’41”S; 54°47’21”W; 06.xii.2019, Santos SE col. ( INPA-EPH 028 ) GoogleMaps . PARATYPE. Nymph (parts on slide), Brazil, Pará, Mojuí dos Campos, Mojuí dos Caboclos stream , 02°42’03”S; 54°41’01”W, 05.vii.2020, Oliveira LA col. ( INPA-EPH 029 ) GoogleMaps .