Anacroneuria flintorum Froehlich, 2002

Almeida, Lucas Henrique De, Gonçalves, Maísa De Carvalho, Novaes, Marcos Carneiro, Paresqui, Rayner Constantino & Bispo, Pitágoras Da Conceição, 2018, Anacroneuria flintorum Froehlich 2002 (Plecoptera: Perlidae): Notes, distribution, and life stages association using molecular tools, Zootaxa 4370 (4), pp. 409-420 : 411-415

Anacroneuria flintorum Froehlich, 2002

Anacroneuria flintorum Froehlich, 2002: 93 ; Bispo & Froehlich, 2004: 99; De Ribeiro & Froehlich, 2007: 55; Froehlich, 2010: 56; Baldin et al., 2013: 394; Gonçalves et al., 2017: 146.

Material examined. BR, SP: Iporanga, Gruta da Tapagem, 15.xi.1991, 1 male; PEI, Rio do Carmo , 19.ii.1992, 1 male; PEI, Rio do Carmo, 16.ii.1993, 2 males; PEI, Rio Poços Altos, 10.xi.1993, CGF & HP col., 2 males; PETAR, Rio Betari, Bairro da Serra, 20.viii.1996, light trap, ASM col., 1 male; PEI, Córrego Lajeado , 24.ii.1999, 2 males; PEI, Córrego Lajeado, 17.ix.1999, 1 male; PEI, Ribeirão Água Comprida, 27.x.1999, 3 males; PEI, Rio do Carmo , 28.x.1999, 1 male; PEI, Ribeirão Água Comprida, 23.xi.1999, 7 males; PEI, Ribeirão Água Comprida, 06.i.2000, 8 males; PEI, Rio Poços Altos, 01.ii.2000, 2 males; PEI, Rio do Carmo, 25.iii.2000, 1 male; PEI, Ribeirão Água Comprida, 24°17’38”S, 48°25’04”W, 30.x.2002, ASM col., 1 male; PECB, Rio Taquaral , 09.ix.2006, 1 male; PEI, Córrego Roda D’Água, 13.xii.2014, light trap, PCB col., 1 female; PEI, Rio do Carmo, bridge, 24°18’15”S, 48°24’31”W, 14.xii.2014, light trap, PCB col., 1 male and 1 female; PEI, Córrego do Mirante , 15.xii.2014, light trap, PCB col., 1 female; PEI, Rio do Carmo, bridge, 24°18’15”S, 48°24’31”W, 08.ii.2017, light trap, LHA et al. col., 1 male; PEI, Ribeirão Bocaina, bridge, 24°16’13”S, 48°27’09”W, 12.ii.2017, light trap, LHA et al. col., 1 male; PETAR Núcleo Santana, Riacho Furnas, 24°32’03”S, 48°42’02”W, 14.ii.2017, light trap, LHA et al. col., 2 males; PETAR Núcleo Santana, Rio Roncador , 24°32’00”S, 48°42’06”W, 15.ii.2017, light pan trap, LHA et al. col., 1 male; PECB, Braço do Rio Taquaral , 24°03’31”S, 47°59’41”W, 05.ii.2017, D-net, LHA et al. col., 1 nymph; PECB, Ribeirão de Pedras, 24°03’40”S, 47°59’51”W, 06.ii.2017, D-net, LHA et al. col., 1 nymph; PECJ, Córrego Campo do Meio 22°41’28”S, 45°28’26”W, 28.i.2009, light trap, 2 males. BR, ES: Caparaó, Rio Santa Marta, 18.ii.2016, FFST col., 3 females and 7 nymph; Caparaó, Pedra Menina, Base, 14-15.ii.2016, FFST col., 2 females; Caparaó, Pedra Menina, Base, 15-16.ii.2016, FFST col., 6 females and 1 male. BR, MG: Araponga , Serra do Brigadeiro , Vale das Luas, 14.i.2014, FFST col. 1 nymph. BR, SC: Chapadão , 28#12’09”S, 49#23’14”W, 15.ii.2013, light trap, L.C. Pinho, A.P. Amaral, M.C. Novaes col., 1 male; Orleans, Rio da Serra, 28°12’43”S, 49#27’28”W, 16.ii.2013, light trap, L.C. Pinho, A.P. Amaral, M.C. Novaes col., 1 male.

Description and association of nymph. Molecular association. We associated adults with nymphs of A. flintorum (including teneral adults) from the states of Espírito Santo and São Paulo. The COI divergences ranged from 0–0.9% for specimens from the São Paulo State and from 0–0.7% from Espírito Santo State. Intraspecific divergences ranged from 0–3.9%, probably due the geographic variation. For all species studied, interspecific divergences ranged from 12.4%, between A. flintorum (PLE481a) and A. sp. 2 (PPI15) to 20.6% between A. flintorum (PLE479a) and A. debilis ( Pictet, 1841) (PLE480b). A dendrogram and the matrix with pair divergence between specimens based on COI sequences are presented in Fig. 1 and Table 2.

Description of nymph. General color dark brown in dorsal view and light yellow in ventral view. Head dark brown with light yellow areas near post-frontal suture, occiput and frontoclypeal region; M-line complete, with well-defined limits; eyes and ocelli black; ocelli with a translucent layer ( Fig. 2A ); clypeus dark brown; labrum light yellow; maxillae light yellow with lacinia light brown and galea brown; mandible black with median region dark brown with f5 pointed teeth on distal margin, decreasing in size toward base, but teeth 3 and 4 similar in size ( Figs. 3A, 3B and 3C ). Pronotum dark brown with thin median line and scattered rugosities light yellow ( Fig. 2A ). Wing pad light with contour partially dark brown ( Fig. 2C ). Leg brown, forefemur with a central pale line without setae and with lateral surface covered by sparse bristles, in dorsal view; forefemur anteriorly and posteriorly with higher density of thick bristles, and posteriorly with fringe of hairs; tibia anteriorly with sparse thick bristles, and posteriorly with a row of thick bristles and a well-developed band of hairs ( Figure 3D ). Abdomen dark brown, almost black, with a drop-shaped light spot in the last segment ( Fig. 2B ). Cerci brown with thick bristles; segments differ in shape and size from base to apex ( Fig. 3E ). Thoracic gills ( Fig. 2D ): ASC1, AT2, AT3 and PT3.

Measurements (n=4): head width 3-5 mm; head length 2-3 mm; antennae length 7-8 mm; pronotum width 3-3.5 mm; pronotum length 1.5- 2 mm; cercal length 9-12 mm; total length 10-15mm.

Adult morphological variation. Examination of specimens from different regions of Atlantic Forest (states of Espírito Santo, Minas Gerais, Santa Catarina, and São Paulo) indicated morphological variation. Forewing length of male adults of A. flintorum range from 10 to 15.2 mm (specimens studied herein and Bispo & Froehlich, 2004; Froehlich, 2010, and Baldin et al., 2013). The dorsal color pattern of head of adult of A. flintorum can be variable, even within the same population ( Bispo & Froehlich, 2004). In addition, it is possible to observe that the dark brown color of recently collected specimens can become ochraceous when preserved in 80% and 100% ethanol for an extended period of time ( Fig. 4 ). Therefore, it is difficult to identify the species by color pattern alone. For identification, it is essential to study the male penial armature, which in A. flintorum is elongated, tapering progressively from base to the apex and has hooks well separated from distal vesicles ( Froehlich, 2002; Bispo & Froehlich, 2004). However, the keel of penial armature may diverge in specimens from the same population and in different populations. In dorsal view, the keel varies from rounded (male specimens from Rio de Janeiro State), pointed (male specimens from PECJ), to convergent or parallel lines (male specimens from PEI). The specimens collected farther north of the species distribution (e. g. ES, RJ and North of SP) have penial armature more robust than specimens from further south (e.g. South of SP and SC).

Teneral adult specimens. Teneral specimens of A. flintorum studied are generally brown in color with pale areas along the body; head and pronotum brown with a pale outline. In these specimens, the pronotum does not have lateral folds at the edges, wings are totally pale and the thoracic segments present remnants of gills ( Figure 5D, 5E and 5F ). A similar pattern to A. flintorum is also present in A. debilis ( Almeida & Duarte, 2017) suggesting that several species may be similar when teneral. Therefore, species described as having pale areas on the head and pronotum and milky wings (e.g. A. petersi Froehlich, 2002 ) may have been based on teneral specimens, requiring caution for use in identifications.

Remarks. The nymph of A. flintorum has a different pattern than the other known Anacroneuria nymphs described from Brazil ( Righi-Cavallaro & Lecci, 2010; Avelino-Capistrano et al., 2011a; Novaes et al., 2012; Righi-Cavallaro & Froehlich, 2013; Ribeiro & Gorayeb, 2014; Gonçalves et al., 2017). The color pattern of the head and the drop-shaped light spot in the last abdominal segment are apparently characteristic for this species. In addition to description of the nymph, we present new species records from the states of Minas Gerais and Santa Catarina. Anacroneuria flintorum has been collected from streams from protected areas of the Atlantic Forest ( Fig. 6 ). In general, these streams are pristine and have fast currents and rocky substrates, and undisturbed channels and banks. This suggests that A. flintorum may be a sensitive taxon to environmental disturbances.

Figures

FIGURE 1. Neighbor-joining tree for cytochrome c oxidase subunit I (COI) sequences (433 bp) from Anacroneuria flintorum Froehlich and related stoneflies from Espírito Santo and São Paulo States, Brazil, modeled by Kimura-2-parameter (K2P).

FIGURE 2. Nymph of Anacroneuria flintorum: head and pronotum (A), abdominal segments and cercus (B), mesonotum and metanotum in dorsal view (C) and ventral view (D).Scale:1 mm.

FIGURE 3. Nymph of Anacroneuria flintorum: labium (A), right mandible (B), right maxilla (C), pronotum left leg, dorsal view (D); cerci inproximal,medial anddistal view (E).Scales:0.5mm for A, B and C; 0.5 mm for D; 0.5mm and 0.25 mm for E, respectively.

FIGURE 4. Males from ES (A), SC (B), PECJ (C) and Paranapiacaba mountains (D and E). Male collected in 2014 (D) and male collected in 1999 (E) not preserved in alcohol.

FIGURE 5. Fully developed specimen: head and pronotum (A), pronotum and mesonotum in lateral view (B) and mesonotum and forewings (C). Teneral specimen: head and pronotum (D), pronotum and mesonotum in lateral view (E), mesonotum and forewings (F). Lateral folds pointed in B and remnants of gills in thoracicsegments in E. Scale:1 mm.

FIGURE 6. Records of Anacroneuria flintorum Froehlich 2002.