Macuxi tunamore, Cruz & Salles & Hamada & Cão, 2020

Cruz, Paulo Vilela, Salles, Frederico Falcão, Hamada, Neusa & Cão, Jesine Netto Fal-, 2020, New genus and species of Baetidae (Insecta: Ephemeroptera) from Brazil, Zootaxa 4729 (1), pp. 127-137 : 129-135

publication ID	https://doi.org/ 10.11646/zootaxa.4729.1.9
publication LSID	lsid:zoobank.org:pub:D8F8621B-4DF9-4216-A2DB-8177851B9B2B
DOI	https://doi.org/10.5281/zenodo.5920955
persistent identifier	https://treatment.plazi.org/id/03C75211-D972-FFD3-FF18-026EFCA5F9C9
treatment provided by	Plazi
scientific name	Macuxi tunamore
status	sp. nov.

Treatment

Macuxi tunamore sp. nov.

Gen. A: Falcão et al. (2011), Cruz et al. (2018a)

Diagnoses. Male imago. Female imago. Mature Nymph. As this genus remains monospecific, we expect that the following characteristics may prove to be of importance for specific diagnoses. Therefore, those characteristics used in the generic section can also be used for specific identification.

Descriptions. Male Imago. Length: Body 2.4 mm (n=1). Head ( Fig. 2A View FIGURE 2 ) black. Turbinate portion of compound eyes brown. Scape, pedicel and flagellum light brown. Thorax ( Figs 2A and 2B View FIGURE 2 ) black. Legs whitish. Forewing with whitish veins; stigmatic area with three cross veins not reaching subcostal vein; marginal intercalary veins paired, absent between IMP1 and A. Hind wing absent. Abdomen ( Figs 2A and 2B View FIGURE 2 ) with terga and sterna I–VI white, VII–X brown; tracheation black. Caudal filaments lost. Genitalia ( Figs 2G and 2H View FIGURE 2 ) with forceps black. Posterior margin of styliger projected ventrally.

Female imago. Length: Body 2.3mm (n=1). Head ( Fig. 2D View FIGURE 2 ) light brown. Scape, pedicel and flagellum light brown. Eyes black. Thorax ( Fig 2D View FIGURE 2 ) light brown. Legs whitish. Forewing with whitish veins; stigmatic area with three cross veins not reaching subcostal vein; marginal intercalary veins paired, absent between IMP1 and A. Hind wing absent. Abdomen ( Figs 2C and 2D View FIGURE 2 ) light yellow, terga VII – X light brown. Terga and sterna with darker longitudinal marks in all segments.

Mature nymph. Length: body: 2.1 – 2.5 mm; cerci: 1.0 mm. (n=2). Head. Coloration: whitish, turbinate portion of male compound eye dark orange. Antenna ( Fig. 4A View FIGURE 4 ) with spines and fine, simple setae on apex of each segment. Lateral branch of epicranial suture curved. Labrum ( Fig. 4B View FIGURE 4 ) with length about 0.6x maximum width. Right mandible ( Fig. 4C View FIGURE 4 ) with incisors 4 + 3 denticles, prostheca robust with two pectinate lobes, margin between prostheca and mola convex without setae. Left mandible ( Fig. 4D View FIGURE 4 ) with incisors 4 + 3 denticles, prostheca robust, bifurcated at middle, both lobes pectinated, margin between prostheca and mola straight without setae Hypopharynx ( Fig. 4E View FIGURE 4 ). Lingua subequal in length than superlingua, with medial lobe, distal margin with short, fine and simple setae; superlingua rounded with short, fine and simple setae scattered over distal margin. Maxilla ( Fig. 4F View FIGURE 4 ). Maxillary palp long, 1.5x length of galea-lacinia, palp article II 0.7x length of article I, apex of article II with small lobe; maxillary palp with few fine and simple setae over surface. Labium ( Fig. 4G View FIGURE 4 ). Glossa inner margin with one row of small stout setae, apex with four long, stout and pectinate setae, ventral surface with one row of fine and simple setae. Paraglossa not curved inward and truncated at apex; ventral surface with simple and fine setae; apex with two rows of long, stout and pectinate setae, dorsal surface with two longitudinal rows of long and stout setae. Labial palp with article I as long as articles II and III combined; article II with dorsal and ventral surface covered with simple, fine and long setae; article III with one small lobe at apex. Thorax. Coloration ( Figs 3 View FIGURE 3 A–3H). Male with thorax dark brown, usually with apical half of forewing pads white; female with thorax whitish, covered with light brown pigmentation, usually with apical half of forewing pads grey. Legs ( Figs 5A and 5B View FIGURE 5 ). Forefemur. Surface with pores; dorsal and ventral margin with one row of short spine-like setae; length of setae about 0.3x maximum width of femur; ventral and dorsal margins with row of blunt and concave setae, apex of setae pectinate. Foretibia. Ventral margin with few short and stout setae. Foretarsus. Dorsal margin with few fine and simple setae; ventral margin with two rows of short and stout setae. Tarsal claw 0.3x the length of tarsi. Middle and hind legs similar to foreleg. Abdomen. Coloration ( Figs 3 View FIGURE 3 A–H). Usually abdominal terga II to VII with one medial mark on anterior margin, and with lateral margins light brown, abdominal terga IX and IX darker, light brown or black; abdominal sterna I to VII with light brown lateral margins. Terga surface creased. Posterior margin without spines. Gills ( Fig. 5C View FIGURE 5 ). Lamella white, tracheae hyaline, ribs fused. Paraproct ( Fig. 5D View FIGURE 5 ) with about eight marginal spines, postero-lateral extension with minute marginal spines. Paracercus ( Fig. 5E View FIGURE 5 ) without spines. Cerci ( Fig. 5F View FIGURE 5 ) with posterior margin without spines, apex of lateral margins with spines on each article.

Comments. Nymphs were collected in fine gravel, sand and clay substrate, where the water flow is low ( Figs 1A and 1B View FIGURE 1 ). Based on substrate characteristics, this new taxon can be classified as psammophilous. Mayflies in this habitat category are considered to have low dispersion capacity and populations with small number of specimens ( McCafferty 1991, Lillie 1995, Glazaczow 1997, Jacobus 2013). Cruz & De-Souza (2014) pointed that these characteristics makes each population unique. Therefore, even when the sampled area, body size and habitat preference allows obtaining very few specimens, the samples should be studied.

Etymology. The species name comes from the combination of the Macuxi words tuna and more, which means “water child”. Macuxi is one of the most spoken languages of Roraima and has been recognize as an official language in some districts. The name is in apposition.

Material examined. Holotype: Male imago with correspondent nymphal exuviae, BRAZIL, Roraima, Caroebe, River Caroebe , vicinal 05, 00°54’47.3”N / 59°34’19.9”W, 24.03.2012, Cruz P. V., Hamada, N., Dantas, G., Boldrini, R. cols., INPA GoogleMaps . Paratypes: One female imago with correspondent nymphal exuviae and four nymphs, same data as holotype. Other material: One nymph on slide, BRAZIL, Roraima, Caroebe, River Caroebe, vicinal 05, 00°54’47.3”N / 59°34’19.9”W, 19.03.2013, Cruz P. V. col., INPA.