Minagrion waltheri (Selys, 1876)

Vilela, Diogo Silva, Anjos-Santos, Danielle, Koroiva, Ricardo, Cordero-Rivera, Adolfo & Guillermo-Ferreira, Rhainer, 2020, Revision of the genus Minagrion Santos, 1965 (Odonata: Coenagrionidae), Zootaxa 4786 (2), pp. 176-198 : 190-192

Minagrion waltheri (Selys, 1876)

Figs. 1f (♂ hab), 2k–l (♂ and ♀ tub), 3u–x (♂ app), 4f (♂ lig.), 5j (♀ hab), 6f (♀ lob), 7e (♀ ptx), 8g–h (♂ app, lost holotype), 9g–i (♀ lost allotype), 10f (alive ♂ specimen)

Agrion (?) waltheri, Selys (1876) : 1286 (original description ♂ and ♀)

Telagrion serracipoense, Santos (1956) : 369 −374 (description ♂ and ♀)

Minagrion waltheri, Santos (1965a) : 9 (new combination);— Santos (1965b): 43 (synonymy of T. serracipoense with M. waltheri );— Lencioni (2004): 91 −92 (relationships with Telagrion );— Lencioni (2006): 173 (illustrated guide, distribution);— Garrison et al. (2010): 287, 288, 289 (synonymy list, illustrations, diagnosis);— Côrtes et al. (2011): 136 (distribution in Tocantins State);— Hämäläinen (2013): 30 (mentions the species named after Walthère de Selys Longchamps);— Machado & Bedê (2015): 294 (distributional record for Minas Gerais);— Bedê et al. (2015): 121 (distributional record for Minas Gerais);— Vilela et al. (2016): 489 (distribution in Minas Gerais State, ecological data);— Renner et al. (2017): 3 −6 (distri- bution in Rio Grande do Sul State);— Rodrigues & Roque (2017): 2 (distribution in Mato Grosso do Sul State);— Dalzochio et al. (2018): 6 (distribution in Rio Grande do Sul State).

Holotype ♂ and allotype ♀: BRAZIL, Minas Gerais State, Serra do Cipó, Municipality of Jaboticatubas , 17.i.1951, N. Santos & J. Machado leg., in MNRJ [examined]

Specimens examined. Total: 18♂♂, 12♀♀. 1♂ (Holotype), 1♀ (Allotype), 5♂♂, 5♀♀ (Paratypes), BRAZIL, Minas Gerais State, Jaboticatubas, Serra do Cipó , 17.i.1951, N.D. Santos & J.P. Machado leg., in MNRJ ; 9♂♂, 5♀♀, Minas Gerais State, São Gonçalo do Rio Preto, Rio Preto State Park , 25.x.2000, L.C. Bedê leg., in ABMM ; 1♀, Minas Gerais State, Morro do Pilar , 13.ii.1965, A. Machado & Bokemann leg., in ABMM ; 1♂, Minas Gerais State, Ouro Preto, Andorinhas Waterfall , 04.ii.1981, in ABMM ; 1♂, Paraná State, Caxambu , 19.vii.1983, Vanedeir leg., in ABMM ; 1♂, Minas Gerais State, Jaboticatubas, Km 121−122, 13.ii.1965, N. Santos & A. Machado leg., in FAAL .

Additions to the original male description. Head ( Fig. 1f ). Dorsally black, except for the small and roughly quadrangular blue post ocular spots merged with occipital bar; frons angulated; postfrons, antefrons, anteclypeus, postclypeus and labrum orange; back of head with a greenish stripe adjacent to each eye; remainder black.

Thorax ( Fig. 1f ). Anterior lobe of prothorax blue, medial lobe black with blue spots on propleuron, posterior lobe black with blue spots laterally. Pterothorax with a thick black dorsal stripe; mesepisternum with a blue longitudinal stripe; mesepimeron black; mesinfraepisternum with 1/2 upper portion black, remainder pale; metepisternum pale green, except for a blue tinge on its posterior 1/ 4 in living specimens, remainder of pterothorax pale green/yellow in living specimens, pale in fixed specimens.

Legs ( Fig. 1f ). Orange/yellow in living specimens, pale in fixed specimens; spination of the legs black.

Wings ( Fig. 1f ). Hyaline with brown parallelogram pterostigma, occupying one cell; 9 Px in HW, 10 Px in FW; CuA extending for 10 cells distal to vein descending from subnodus in FW and HW; MP not reaching wing posterior margin and merged with MP&AA in FW and HW.

Abdomen ( Fig. 1f ). Bright yellow/orange in living specimens, pale yellow in fixed specimens, except: S1 with a black spot on anterior dorsum, tubercle with digit like shape and a rounded apex; S6 gradually darkening from front to rear; S7 black, except for orange/pale coloration ventrally; dorsal S8−S9 with roughly triangular blue spots; S10 blue.

Genital ligula ( Fig. 4f ). Segment one with a pair of roughly triangular lateral sclerotized processes, similar to lobes, in the flexure; inner fold triangular in lateral view, proximal to flexure. Segment two long with an entire straight apex, with two lateral lobes.

Anal appendages ( Figs. 3 u–x, 8g–h). Dorsal plate of the cercus broad; ventrobasal portion only 1/5 of the cercus length; paraprocts small, apex acute curved upwards.

Measurements. Total 32−35; abdomen 26−29; FW 16−20; HW 15.5−16.

Additions to the original female description. Head ( Fig. 5j ). Similar to male in color pattern, except for paler colors in the non−black areas.

Thorax ( Figs. 5j , 6f , 7e , 9j ). Overall thoracic coloration similar to males, except for a thin blue stripe on mesopleural suture. Posterior lobe of prothorax trilobed in dorsal view, middle lobe the larger; lateral lobes erect, middle lobe posteriorly directed in lateral view; lateral margin of prothorax slightly widens towards the base, notopleural suture a nearly straight line.

Legs ( Fig. 5j ). Pale in fixed specimens; spination similar to the males.

Wings ( Fig. 5j ). Hyaline with light brown parallelogram pterostigma, occupying one cell; 9 Px in HW, 10 Px in FW; CuA extending for 9 cells distal to vein descending from subnodus in FW and HW; MP not reaching wing posterior margin and merged to MP&AA in FW and HW.

Abdomen ( Figs. 2l , 5j , 9 k–l). Similar to males in coloration, except for the blue areas smaller, replaced with black. Tubercle digit-like, smaller than in males, with a rounded apex. Ovipositor surpasses the S10 for a distance shorter than this segment, not reaching the cercus level.

Measurements. Total 32−35; abdomen 26−29; FW 18; HW 16.5−18.

Diagnosis. Males and females of M. waltheri share with M. mecistogastrum a digit-like tubercle with a rounded apex, but are easily distinguished from the latter species by large size difference, male cercus morphology and female prothoracic morphology. Minagrion waltheri differs from its other congeners in the following combination of characters: male cercus with a large and broad dorsal plate, thinner in all other species; a very small ventrobasal portion, occupying 1/5 of cercus length, on remaining species occupying at least 1/2 of cercus; genital ligula with lateral lobes on segment two; female posterior lobe of prothorax trilobed, middle one largest (only shared with M. mecistogastrum ), and notopleural suture nearly a straight line (only shared with M. ribeiroi ).

Distribution. Unlike other species of Minagrion , M. waltheri has a wide distribution in Brazil and is the only species in the genus recorded in four of the five Brazilian regions: North, Center–West, Southeast and South.

Figures

FIGURE 1. Male habitus: (a) caldense, São Roque de Minas, at ECOEVO; (b) caldense, Poços de Caldas, at FAAL; (c) canaanense, Santa Tereza, at FAAL; (d) mecistogastrum, Salesópolis, at FAAL; (e) ribeiroi, Recreio dos Bandeirantes PARATYPE, at FAAL; (f) waltheri, São Gonçalo do Rio Preto, at ABMM.

FIGURE 2. S1 tubercle; (a) ♂ caldense, Poços de Caldas, at FAAL; (b) ♂ caldense, São Roque de Minas, at LESTES; (c) ♀ caldense ALLOTYPE, Poços de Caldas, at MNRJ; (d) ♀ caldense, SCNP, at ECOEVO; (e) ♂ canaanense, Santa Tereza, at FAAL; (f) ♀ canaanense ALLOTYPE, Santa Tereza, at MNRJ; (g) ♂ mecistogastrum, Salesópolis, at FAAL; (h) ♀ mecistogastrum, Salesópolis, at FAAL; (i) ♂ ribeiroi, Recreio dos Bandeirantes PARATYPE, at FAAL; (j) ♀ ribeiroi, Salesópolis, at FAAL; (k) ♂ waltheri, São Gonçalo do Rio Preto, at ABMM; (l) ♀ waltheri, São Gonçalo do Rio Preto, at ABMM.

FIGURE 3. Male anal appendages; (a–d) ♂ caldense, Poços de Caldas, at FAAL; (e–h) ♂ caldense, São Roque de Minas, at LESTES; (i–l) ♂ canaanense, Santa Tereza, at FAAL; (m–p) ♂ mecistogastrum, Salesópolis, at FAAL; (q–t) ♂ ribeiroi, Recreio dos Bandeirantes PARATYPE, at FAAL; (u–x) ♂ waltheri, Jaboticatubas, at FAAL.

FIGURE 4. Male genital ligula; (a) caldense, Poços de Caldas PARATYPE, at MNRJ probably lost; (b) caldense, SCNP PARA- TYPE of M. franciscoi, at ABMM; (c) canaanense, Santa Tereza, at RWG; (d) mecistogastrum, Cachoeira de Macacu, at RWG; (e) ribeiroi, Recreio dos Bandeirantes, at RWG; (f) waltheri, São Gonçalo do Rio Preto, at ABMM.

FIGURE 5. Female habitus; (a–c) juvenile caldense, SCNP, at LESTES; (d–f) mature caldense, SCNP, at LESTES; (g) caldense, Poços de Caldas PARATYPE, at ABMM; (h) mecistogastrum, Salesópolis, at FAAL; (i) ribeiroi Salesópolis, at FAAL; (j) waltheri, São Gonçalo do Rio Preto, at ABMM.

FIGURE 6. Female posterior lobe of prothorax; (a) caldense, Poços de Caldas ALLOTYPE, at MNRJ; (b) caldense, SCNP, at ECOEVO; (c) canaanense, Santa Tereza ALLOTYPE, at MNRJ; (d) mecistogastrum, Salesópolis, at FAAL; (e) ribeiroi, Salesópolis, at FAAL; (f) waltheri, São Gonçalo do Rio Preto, at ABMM.

FIGURE 7. Female prothorax in lateral view; (a) caldense, Poços de Caldas PARATYPE, at ABMM; (b) canaanense, Santa Tereza ALLOTYPE, at MNRJ; (c) mecistogastrum, Salesópolis, at FAAL; (d) ribeiroi, Salesópolis, at FAAL; (e) waltheri, São Gonçalo do Rio Preto, at ABMM.

FIGURE 9. Female structures of Minagrion allotypes probably lost during the fire at MNRJ in 2018; (a–c) caldense, Poços de Caldas; (d–f) canaanense, Santa Tereza; (g–i) ribeiroi (Telagrion ribeiroi), Recreio dos Bandeirantes; (j–l) waltheri (Telagrion serracipoense), Jaboticatubas.