Megaloprepus caerulatus Drury, 1782

Feindt, Wiebke & Hadrys, Heike, 2022, The damselfly genus Megaloprepus (Odonata: Pseudostigmatidae): Revalidation and delimitation of species-level taxa including the description of one new species, Zootaxa 5115 (4), pp. 487-510 : 498-500

Megaloprepus caerulatus Drury, 1782

( Figures 5 , 6 , 7 , 8 , 9 )

Libellula caerulata Drury 1782: 75 , Plate 50, Fig. 1 (first species report and illustration of a male specimen).

Megaloprepus caerulatus Rambur, 1842: 290–291 (transfer to Megaloprepus and description of diagnostic characters); Selys 1860: 12–13 (species description and diagnostic characters); Selys 1886: 6–7 (remarks to the species description 1860); Calvert 1901 –1908: 51–53, 417 (description); Ris 1916: 64–69, 189 (description of male and female, diagnostic characters); Ramírez 1997: 6 (description and illustration of the larvae); Hedström & Sahlén 2001: 1037–1056, Figs. 2 , 6a–b , 12a–b, 17a–b (description); Hedström & Sahlén 2003: 9 (extended description of the larvae); Heckman 2008: 201–203, Fig. 3.1 .210 (key to the genus); Garrison et al. 2010: 394, Figs. 2544, 2546, 2572–2576, Map 106 (description).

Holotype. Unknown.

Specimens examined. (81 specimens).

1♂ 1♀ (RBINS: E. Selys Longchamps ) ; 1♂, San Carlos (RBINS: E. Selys Longchamps).— Central America : 2♂♂ 1♀, leg. Weicht (RBINS: E. Selys Longchamps).— Nicaragua, Indio Maíz Biological Reserve, Refugio Bartola : 3♂♂ 3♀♀, N 10°58’30.78” W 84°20’06.00”, 77–110 m, xi. and xii. 2011, leg. W. Feindt. — Costa Rica, Conservation area Tortuguero, Tortuguero National Park : 1♀, vii. 1968 (AMNH); Estación Cuatro Esquinas: 1♂ 1♀, N 10°32’22.38” W 83°30’23.33”, 10 m, iii. 1989, leg. R. Aguilar (INBio: INBIOCRI000686309) and iv. 1989, leg. R. Delgado (INBio: INBIOCRI000575917); Conservation area Cordillera Volcánica Central, Puerto Viejo de Sarapiqui, Biological Research Station La Selva : 5♂♂ 1♀, N 10°25’19.74” W 84°00’35.22”, 61–97 m, xii. 2011 and iv. 2012, leg. W. Feindt; Selva Verde Lodge: 1♀, N 10°26’30.22” W 84°1’30.56”, 62 m, 1991 (AMNH); Braulio Carrillo National Park, Estación Magsaysay : 2♂♂, N 10°24’04.52” W 84°02’57.53”, 200 m, i. 1991, leg. A. Fernandez (INBio: INBIOCRI000218397, INBIOCRI000218396); 1♂ 1♀, N 10°24’07.78” W 84°03’00.82”, 160 m, iii. 1991, leg. M.A. Zumbado (INBio: INBIOCRI001112977, INBIOCRI001112978); Estación Cuarillo: 1♀, leg. A. Chacón (INBio: INBIOCRI001101165); Hitoy Cerere, Cuenca del Estrella : 1♂, N 9°40’15.73” W 83°01’34.16”, 250 m, x. 2000, leg. L. Chavarría (INBio: INB0004284813). Cairo: 1♂, N 10°5’8.06” W 83°31’42.11”, 304 m, i. 1931 (AMNH).— Panama : 4♂♂ 4♀♀ (RBINS: E. Selys Longchamps); Barro Colorado Nature Monument, Barro Colorado Island : 11♂♂ 4♀♀, N 9°9’41.41” –9°9’15.48” W 79°50’30.97” –79°51’3.11”, 140–180 m, xi. 1929 (AMNH), i. and xi. 1929, leg. C.H. Curran (AMNH), ii. and iii. 1936, leg. W.J. Gertsch (AMNH), ii. and iii. 1936, leg. F.E. Lutz (AMNH), xi. 1930, leg. E.I. Huntington (AMNH), xi. 1930, leg. Donato (AMNH: F30III2D), iii. 1933 (AMNH: F330313C).— Colombia : 9♂♂ 1♀, 1934, leg. F. Ovalle (AMNH: Ac 33501) ; 1♂ 1♀, 1934 (AMNH: Ac 4639); Bogota : 11♂♂ 3♀♀ (RBINS: E. Selys Longchamps); Caldas, Norcasia, Finca Germánica : 1♀, N 5°34’1.2” W 75°39’32.4”, 800 m, v. 2015, leg. P. Cardozo (ANDES-E: 21017).— Ecuador, Esmeraldas : 1♂ 2♀♀, (RBINS: E. Selys Longchamps ) .

Other material examined (8 specimens): Costa Rica, Conservation area Cordillera Volcánica Central , Biological Research Station La Selva : 3♀♀, N 10°5’8.06” W 83°31’42.11”, 304 m, vi. 2003, leg. R. Vargas (UCMS) and N 10º25’48.43” W 84º0’44.66”, 63 m, i. 1998 and i. 1999, leg. R. Vargas and D. Wagner (UCMS) ; Braulio Carrillo National Park : 1♂, N 10º16’50.28” W 84º6’12.35”, 1050 m, iii. 2001, leg. D. Brenes (UCMS) ; Rio Cantarana : 2♀♀, N 10º21’40.14” W 84º3’19.62”, 324 m, iii. 2004, leg. E. Lopez (UCMS) ; El Ceibo Ranger Station: 1♂, N 10º18’1.42” W 84º5’38.37”, 760 m, ii. 2003, leg. S. Gaimari (UCMS) ; Rio Bijagual: 1♀ (UCMS), N 10º19’32.32” W 84º5’22.92”, 507 m, iii. 2001, leg. E. Corrales (UCMS) .

Note. Analyzed specimens that do not already belong to a collection will stay at the ITZ-Division of Ecology and Evolution, University of Veterinary Medicine Hanover, Germany. The section ‘ other material ’ includes adult samples from the Biological Collection at the University of Connecticut, Storrs, USA.

Mature male. Head. Labium yellow becoming dark brown at anterior margin. Mandible base greenish turning into black towards anterior margin. Gena greenish yellow. Labrum, anteclypeus, postclypeus and frons shining black. Antennae black with a dark yellow ring around base. Vertex and rear of head black, ocelli dark yellow to light brown. Eyes bicolored, dorsal dark green turning almost black and ventral green forming a line with gena.

Thorax ( Fig. 5 ). Prothorax black. Anterior lobe at both sides with additional small oval yellow spots, disposed transversally, and a bigger rhombic central mark. Posterior lobe on both sides with yellow to green comma-shaped spots and a small central yellow isosceles triangle. Both anterior and posterior lobes smoothly rounded, distal margin of posterior lobe slightly turned upward. Propleuron slightly convex and mostly green coloration, distal margins broadly light yellow ( Fig. 5a, b ). Pterothorax black with yellow antehumeral stripe covering 80% of its total length, appearing interrupted at distal-dorsal end of mesinfraepisternum; outer ends of mesostigmal plates pointed, with dark yellow spots; short yellow stripe at proximal end of mesepisternum close to humeral suture; yellow stripe covering metepisternum also includes lower ventral portion of mesepimeron and metastigma at its lower border, decreases in width towards wing bases between FW and HW; metepimerum yellow with a smaller green stripe. Venter yellow with pruinescence continuing to entire coxae. Coxae yellow-green with small, light brown-black markings. Remaining internal and dorsal side of legs black, inner surface of femora green, external side of tibiae dark yellow. Tarsi, spines, and claws entirely black. Two rows of spines on femora and tibiae, centrally directed.

Wings ( Fig. 6 ). Wings stalked, long and very broad, wingtips smoothly rounded (greatest surface); mostly hyaline except a broad, dark metallic blue band crossing last third of all four wings. Milky-white coloration at wingtips minimized to two cell rows between blue band and pseudostigma at anterior wing margin and one distal of blue band at posterior wing margin, barely visible. Pseudostigma dark blue, extends between five and six cells in FW, four and five cells in HW. Area basal of CuA very broad, CuA forks 3–5 (rarely six) times, and secondary branching very common. MP forks distant from wing margin: number of cells between bifurcation and wing margin 9–19 in HW, 8–15 in FW (N = 30). Wings dimorphic, males with an additional matte milky-white band proximal to blue band, more than half width of blue band.

Abdomen. Abdomen slender and elongate, black with slightly metallic brown to bluish sheen as ground color. S1–4 with light green to yellow as follows: in S1 and S2 entire lateral terga; S3 with 80% and S4 with 25% of ventral parts of tergites dark yellow, expanding in width to posterior parts of segments.

Genital ligula ( Fig. 7 ). Second segment with a very prominent inner fold, containing sclerotized hair-like structures on both sides. Lateral lamina of distal s2 starts at sides of inner fold, widely framing distal half of s2 and forming apical lobe. Filamentous whip-like distal segment slightly thickened proximally, containing ventrally directed flattened oval process close to base.

Caudal appendages ( Fig. 8 ). Appendages small. Cercus nearly hairless, black, biramous, both ends acute in lateral view, dorsal branch slightly hairy, directed dorso-distal, inner branches point parallel aligned to ventral, hidden between paraprocts base. Paraproct longer than cercus, slightly hairy, light brown to yellow, laterally viewed shape of a triangle with a steeply, acuminate dark brown-black tip directing dorso-distal. Paraprocts in lateral view roughly triangular with A and B slightly convex and sub-equal, D = 66% of L – L’ length.

Measurements. ♂ AL 60.5–104.0, mean: 84.0±6.7, FWL 43.0–87.1, mean: 69.0±7.9 (N = 102). ♀ AL 61.0– 97.1, mean: 76.9± 7.8, FWL 50.8–81.2, mean: 65.1± 6.9 (N = 32). Wings: width/length ratio FW 0.25±0.01, HW 0.25±0.01 (N = 30); blue band width at the costa FW 18.5±2.8, HW 17.9±2.8 (N = 30); ratio width of blue stripe/ wing length FW 0.25±0.02, HW 0.25±0.03 (N = 30).

Remarks. Megaloprepus caerulatus shows the largest size variation in abdominal length and wing length, mostly studied and observed on Barro Colorado Island, Panama. The yellow antehumeral stripe sometimes covers almost the whole pterothorax. The pruinescence on the ventral side of the thorax and the entire coxae can also include the femora. A few males have additional bluish green coloration on the black labrum in transition to the anteclypeus. Paraprocts sometimes very hairy and in one specimen A appeared straight (N = 10).

In females the proximal white band is not present, but they have very bright, shining white dots at the wingtips in the emarginations of the blue band (at the costa between the blue band and the pseudostigma as well as on the posterior side of the wing distal to the blue band).

Range. The known distribution of M. caerulatus covers southern Central America (Southern Caribbean coast of Nicaragua (Indio Maíz Biological Reserve), the Caribbean slope of Costa Rica (National Park Tortuguero, Biological Research Station La Selva, Hitoy-Cerere Biological Reserve) and Barro Colorado Island in Panama) and South America (Northern part of Colombia at the Caribbean side, and on the Pacific side of the Andes ranging from Colombia to Peru (West of the Andes)).

Figures

FIGURE 1. Geographic origin of the material included in this study. Each species is displayed using different colorations.

FIGURE 2. Megaloprepus diaboli sp. nov. color patterns: (a) lateral view of prothorax, pterothorax including mesostigmal plates, wing base and coxa; (b) dorsal view of prothorax. al: prothorax anterior lobe. pl: prothorax posterior lobe. mp: mesostigmal plates. cx1–3: coxae.

FIGURE 3. Megaloprepus latipennis color patterns: (a) lateral view of prothorax, pterothorax including mesostigmal plates, wing base and coxa; (b) dorsal view of prothorax. al: prothorax anterior lobe. pl: prothorax posterior lobe. mp: mesostigmal plates. cx1–3: coxae.

FIGURE 5. Megaloprepus caerulatus color patterns: (a) lateral view of prothorax, pterothorax including mesostigmal plates, wing base and coxa; (b) dorsal view of prothorax. al: prothorax anterior lobe. pl: prothorax posterior lobe. mp: mesostigmal plates. cx1–3: coxae.

FIGURE 6. Left hindwings of the four Megaloprepus species. The metallic blue wing band proximal of the pseudostigma was integrated to visualize its variation, whereas the additional matte white band of M. caerulatus could not be pictured (but see Fig. 9). The scale bar indicates 1 cm.

FIGURE 7. Ventral and lateral views of the genital ligula of the four Megaloprepus species. M. caerulatus, M. latipennis and M. brevistigma show significant differences in the inner process of the third segment (s3), M. diaboli sp. nov. constitutes an intermediate position. The scale bar indicates 100 μm.

FIGURE 8. Lateral views of the male caudal appendices. The scale bar indicates 0.1 cm.

FIGURE 9. Megaloprepus caerulatus in copulation wheel on Barro Colorado Island (Panama) highlighting the sexual dimorphism.