Platybaetis bishopi Müller-Liebenau, 1980

Sutthinun, Chanaporn, Gattolliat, Jean-Luc & Boonsoong, Boonsatien, 2018, A new species of Platybaetis Müller-Liebenau, 1980 (Ephemeroptera: Baetidae) from Thailand, with description of the imago of Platybaetis bishopi Müller-Liebenau, 1980, Zootaxa 4378 (1), pp. 85-97 : 86-89

Platybaetis bishopi Müller-Liebenau, 1980

( Figs.1–2 , 5–10 , 11, 12 , 15 , 17, 19 , 26 , 33–34 )

Material examined: THAILAND: Borwee resort, Suan Phueng district , Ratchaburi province, 13° 28’ 42” N 99° 14’ 54” E, alt. 178 m, 15-XI-2014, C. Sutthinun leg.: 9 L, 2 last instar L on microscope slides, 1 male I (reared) , 2 female I (reared) ( ZMKU). Huai Borklung, Suan Phueng district , Ratchaburi province, 13° 31’ 27” N 99° 14’ 39” E, alt. 170 m, 15-XI-2014 , C. Sutthinun leg. ( ZMKU): 1 L and 1 last instar L on microscope slides. Borwee waterfall, 13° 28’ 33” N 99° 14’ 27” E, alt. 209 m, 29-XI-2014 , C. Sutthinun leg. ( ZMKU): 6 L; 2 mature L (GBIFCH00238460, MZL) and 2 L on microscope slides (GBIFCH00585173, GBIFCH00585174, MZL). Klong Lum Pi Naa, Yan Ta Khao district , Trang province, 07° 28’ 54.7” N 99° 47’ 18.0” E, alt. 43 m, 18-V-2017 , C. Sutthinun leg. ( ZMKU): 9 L. Ton Sa Tor waterfall, Pa Bon district , Phatthalung province, 07° 11’ 72.3” N 100° 04’ 29.2” E, alt, 101 m, 12-III-2016 , B. Boonsoong leg. ( ZMKU): 12 L ( ZMKU). Ton Phrae Thong waterfall, Srinagarindra district, Phatthalung province , 07° 29’ 13.7” N 99° 53’ 59.0” E, alt. 90 m., 17-V-2017 , C. Sutthinun leg. ( ZMKU): 6 L. Khao Khram waterfall, Srinagarindra district , Phatthalung province, 07° 51’ 84.6” N 99° 87’ 35.3” E, alt. 87 m, 19-V-2017 , C. Sutthinun leg. ( ZMKU): 11 L. Klong Tha Di 1, Lan Saka district , Nakhon Si Thammarat province, 08° 27’ 03.3” N 99° 44’ 48.9” E, alt. 236 m, 15-V-2017 , C. Sutthinun leg. ( ZMKU): 14 L. Klong Tha Di 2, Lan Saka district , Nakhon Si Thammarat province, 08° 27’ 21.7” N 99° 44’ 37.2” E, alt. 238 m, 15-V-2017 , C. Sutthinun leg. ( ZMKU): 3 L. Ton Nga Chang waterfall, Hat Yai district , Songkhla province, 06° 56’ 94.0” N 100° 14’ 10.2” E alt 119 m, 12-III-2016 , B. Boonsoong leg. ( ZMKU): 14 L. Boripat waterfall, Rattaphum district , Songkhla province, 06° 59’ 70.2” N 100° 09’ 05.6” E alt 171 m, 12-III-2016 , B. Boonsoong leg. (ZMKU): 16 L.

Larva. ( Figs. 5–10 ) See Müller-Liebenau (1980a). EXcept shape of the labrum with a shallow indentation in the middle of fore margin in the original description ( Müller-Liebenau 1980a, Fig. 1a ), while labrum of our specimens with a more straight margin and more eXpanded laterally ( Fig. 5 ). Claw with one row of ca 8–9 teeth increasing in size towards apeX ( Fig. 26 ), in contrast to the figure in the original description, where two most apical teeth are drawn as much bigger than others ( Müller-Liebenau 1980a, Fig. 2b ).

Male imago. ( Fig. 11 , 15 , 17,19 )

Measurement. Body 6.3 mm; forewing 6.2 mm.

Head. Whitish; scape and pedicel apeX dark brown, flagellum medium brown to colourless. Facetted surface of turbinate eyes orange, lateral face reddish apically.

ThoraX. Light brown, with a few small diffusive yellowish striped on median suture. Pronotum with a pair of black stripes. Anteronotal protuberance flattened and not prominent. All legs pale whitish. Foreleg femora with brownish macula; middle and hind legs femora with oval shaped brownish mark; tarsi blackish. Proportions of forelegs: tibia 1.6 of femur length; tarsus shorter than tibia. Proportions of middle and hind legs: tibia 1.3–1.4 of femur length; tarsus 2.5 times shorter than tibia. Forewing ( Figs. 11 , 15 ) with a dark brown and orange base; longitudinal veins colorless eXtensively bordered with dark brown in proXimal fourth; other parts of membrane colorless; cross-veins thickened and blackish. Two marginal intercalaries in every space between main veins, equal or slightly longer than distance between surrounding veins; pterostigma with 4–5 oblique cross-veins. Hindwing absent.

Abdomen. Abdominal terga ( Fig. 17 ) and sterna translucent, eXcept terga VIII–X white. Terga III–VII with a pair of orange brown stripes on each side; tergum V with thin stripes; tergum IX with round brownish maculae medially. Cerci colourless.

Genitalia colourless ( Fig. 19 ), with 3-segmented gonopods, limit between first and second segments barely visible. Unistyliger with a pointed apophysis at apeX of inner margin; first segment stout, without setae; second segment with subparallel margins widened apically; third segment short, oval.

Female imago. ( Fig. 12 )

Measurement. Body 5.7–7.1 mm; forewing 6.4–7.1 mm.

Head. Yellowish. Antenna with scape and pedicel medium to dark brown, flagellum medium brown to ecru.

ThoraX. Similar to male imago eXcept greyish, with a few diffusive blackish maculae on medioscutum. Foreleg femora with large, diffusive, brownish macula; middle and hind legs femora with oval shaped brownish marked. Proportions of forelegs: tibia 1.2 of femur length; tarsus shorter than tibia. Proportions of middle and hind legs: tibia 1.2 of femur length; tarsus 2.6–3.0 times shorter than tibia. Tarsus of middle and hind legs with 2 apical spines (on 1st+2nd and on 3rd tarsomeres). Forewing as in male eXcept diffusive, blackish macula stretched from stigmatic area to apeX.

Abdomen. Abdominal terga and sterna greyish brown. Terga III, IV, VI and VII with pair of dark brown stripes on each side; tergum V with thin stripes nearly absent; tergum VIII with no marks; tergum IX with or without a group of brownish points medially. ApeX of sternum IX yellowish, with deep V-shape median insertion. Cerci colourless.

Figures

FIGURES 1–4. Female mature larva (1) and male mature larva (in alcohol) (2) of P. bishopi Müller-Liebenau, 1980 (Ratchaburi province), dorsal view; female immature larva (3) and male immature larva (in alcohol) (4) of P. nayokensis sp. nov. (Nakhon Nayok province), dorsal view.

FIGURES5–10. P.bishopi Müller-Liebenau, 1980, larva.(5) labrum,ventral view; (6) canine and molar area of left mandible, dorsal view; (7) canine and molar area of right mandible, dorsal view; (8) labium, ventral view (arrow = clavate bristle); (9) tergum IV–VI; (10) distal margin of tergite V. Scale = 100 µm.

FIGURES 11–14. Male imago (11) and female imago (12) of P.bishopi Müller-Liebenau, 1980 (Ratchaburi province), dorsal view; male imago (13) and female imago (14) of P. nayokensis sp. nov. (Nakhon Nayok province), dorsal view.

FIGURES 15–16. Forewing (15) of P. bishopi Müller-Liebenau, 1980 male imago (Ratchaburi province), dorsal view; (16) forewing of P.nayokensis sp. nov. male imago (Nakhon Nayok province), dorsal view.Scale bar = 0.5 mm.

FIGURES 17–20. Abdominal pattern (17) of P. bishopi Müller-Liebenau, 1980 male imago (Ratchaburi province), dorsal view; (18) abdominal pattern of P. nayokensis sp. nov. male imago (Nakhon Nayok province), dorsal view; (19) genitalia of P. bishopi Müller-Liebenau, 1980 male imago (Ratchaburi province), ventral view; (20) genitalia of P. nayokensis sp. nov. male imago (Nakhon Nayok province), ventral view.Scale bar = 0.5 mm (17–18), 0.2 mm (19–20).

FIGURES 21–26. P. nayokensis sp. nov., larva. (21) labrum, dorsal view; (22) labrum, ventral view; (23) glossa and paraglossa, dorsal view; (24) glossa and paraglossa, ventral view; (25) foreleg claw; (26) foreleg claw of P. bishopi Müller- Liebenau, 1980. Scale bar = 0.2 mm (21–24), 0.1 mm (25–26).

FIGURES 33–36. Larva (33, arrow) and habitat (34) of P. bishopi Müller-Liebenau, 1980 (Ratchaburi province); larva (35, arrow) and habitat (36) of P. nayokensis sp. nov. (Nakhon Nayok province).