Bungona (Chopralla) bintang Gattolliat & Marle

Marle, Pierre, Salles, Frederico F. & Gattolliat, Jean-Luc, 2016, Two new species of Bungona Harker, 1957 (Ephemeroptera: Baetidae) from Borneo, Indonesia, Zootaxa 4088 (2), pp. 221-235 : 227-232

Bungona (Chopralla) bintang Gattolliat & Marle n.sp.

Figures 19–36

Material examined. Holotype: B0521C ( GBIFCH00238399 ): ♂ larva; Indonesia; East Kalimantan; Seturan (2001-bloc 57); Bas. Malinau; Riv. Tamalang (Seturan tributary ); Long/Lat 116°30'29''E / 2°59'50''N; 150 m.a.s.l.; 19.vii.2000. ( MZL). Coll. P. Derleth. Paratypes: B0521C GBIFCH00238421) 2 ♂ larvae, 6 ♀ larvae same data as holotype (in LIPI). B0713A (GBIFCH00238387) + B0713P (GBIFCH00238388): 2 ♂ larvae; Indonesia; East Kalimantan; Seturan (2000-bloc 44-45); Bas. Malinau; Riv. Wok (Sungai Guang) (Seturan tributary); Long / Lat 116°33'11''E / 2°59'12''N; 205 m. a.s.l.; 05.iv.2001. ( MZL). B0433D (GBIFCH00238389) + B0433P (GBIFCH00238402): 1 ♂ larva, 3 ♀ larvae; Indonesia; East Kalimantan; Langap Sud (1995); Bas. Malinau; Riv. Ngayo (Rian tributary); Long / Lat 116°30'58''E / 3°04'56''N; 160 m. a.s.l.; 14.iv.2001. ( MZL). B0711P (GBIFCH00238390): 1 ♀ larva; Indonesia; East Kalimantan; Seturan (2000-bloc 44-45); Bas. Malinau; Riv. Wok (Sungai Guang) (Seturan tributary); Long / Lat 116°33'11''E / 2°59'12''N; 205 m. a.s.l.; 17.vi.2000. ( MZL). B0513C (GBIFCH00238391): 1 ♀ larva; Indonesia; East Kalimantan; Seturan (2001-bloc 57); Bas. Malinau; Riv. Tamalang (Seturan tributary); Long / Lat 116°30'29''E / 2°59'22''N; 160 m. a.s.l.; 10.iv.2001. ( MZL). B0431P (GBIFCH00238403): 1 ♂ larva, 1 ♀ larva; Indonesia; East Kalimantan; Seturan camp; Bas. Malinau; Riv. Seturan; Long / Lat 116°30'36''E / 3°00'20''N; 140 m. a.s.l.; 13.vii.2000. ( MZL). B0521A (GBIFCH00238407) + B0521B (GBIFCH00238409), B0521P(GBIFCH00238401): 1 ♂ larva, 2 ♀ larvae; Indonesia; East Kalimantan; Seturan (2001-bloc 57); Bas. Malinau; Riv. Tamalang (Seturan tributary); Long / Lat 116°30'29''E / 2°59'50''N; 150 m. a.s.l.; 19.vii.2000. ( MZL). B0531A(GBIFCH00238424) + B0531D (GBIFCH00238400): 2 ♀ larvae; Indonesia; East Kalimantan; Seturan (2001-bloc 57); Bas. Malinau; Riv. Tamalang (Seturan tributary); Long / Lat 116°30'46''E / 2°59'22''N; 155 m. a.s.l.; 08.viii.2000. ( MZL). B0813A (GBIFCH00238412) + B0813P (GBIFCH00238392): 2 ♀ larvae; Indonesia; East Kalimantan; Seturan (2000-bloc 43); Bas. Malinau; Riv. Temalat (Sungai Guang) (Seturan tributary); Long / Lat 116°33'29''E / 2°59'29''N; 230 m. a.s.l.; 16.iv.2001. ( MZL). B0811P (GBIFCH00238414): 1 ♂ larva, 1 ♀ larva; Indonesia; East Kalimantan; Seturan (2000-bloc 43); Bas. Malinau; Riv. Temalat (Sungai Guang) (Seturan tributary); Long / Lat 116°33'29''E / 2°59'29''N; 230 m. a.s.l.; 18.vi.2000. ( MZL). B1113A (GBIFCH00238404): 1 ♀ larva; Indonesia; East Kalimantan; Seturan (1999-bloc 27); Bas. Malinau; Riv. Seturan; Long / Lat 116°30'31''E / 3°00'57''N; 235 m. a.s.l.; 26.iii.2001. ( MZL). B1011P2 (GBIFCH00238405): 1 ♀ larva; Indonesia; East Kalimantan; Seturan (1998-bloc 32-33); Bas. Malinau; Riv. Rian; Long / Lat 116°32'16''E / 3°00'57''N; 250 m. a.s.l.; 0 3.08.2000. ( MZL). B1313A (GBIFCH00238410) + B1313B (GBIFCH00238408) + B1313P (GBIFCH00238393): 12 ♂ larvae, 5 ♀ larvae; Indonesia; East Kalimantan; Seturan (unexploited); Bas. Malinau; Riv. Seturan; Long / Lat 116°30'48''E / 3°00'05''N, 235 m. a.s.l.; 28.iii.2001. ( MZL). B0511C (GBIFCH00238416): 1 ♂ larva; Indonesia; East Kalimantan; Seturan (2001-bloc 57); Bas. Malinau; Riv. Tamalang (Seturan tributary); Long / Lat 116°30'29''E / 2°59'22''N; 225 m. a.s.l.; 18.vii.2000. ( MZL). B0541P (GBIFCH00238419): 4 ♂ larvae, 3 ♀ larvae; Indonesia; East Kalimantan; Seturan (2001-bloc 57); Bas. Malinau; Riv. Tamalang (Seturan tributary); Long / Lat 116°30'46''E / 2°59'22''N; 135 m. a.s.l.; 19.viii.2000. ( MZL). B1211B (GBIFCH00238396): 1 ♂ larva, 3 ♀ larvae; Indonesia; East Kalimantan; Langap Sud (1999-bloc 24); Bas. Malinau; Riv. Rian; Long / Lat 116°31'05''E / 3°01'40''N; 135 m. a.s.l.; 11.vii.2000. ( MZL). B0113C (GBIFCH00238397): 3 ♀ larvae; Indonesia; East Kalimantan; Langap Sud (1997-bloc 6); Bas. Malinau; Riv. Belakau (Rian tributary); Long / Lat 116°30'26''E / 3°04'04''N; 100 m. a.s.l.; 20.iv.2001. ( MZL). B0533C (GBIFCH00238386): 1 ♂ larva, 3 ♀ larvae; Indonesia; East Kalimantan; Seturan (2001-bloc 57); Bas. Malinau; Riv. Tamalang (Seturan tributary); Long / Lat 116°30'46''E / 2°59'22''N; 135 m. a.s.l.; 11.iv.2001. ( MZL). B0511P: 2 ♂ larvae; Indonesia; East Kalimantan; Seturan (2001-bloc 57); Bas. Malinau; Riv. Tamalang (Seturan tributary); Long / Lat 116°30'29''E / 2°59'22''N; 225 m. a.s.l.; 18.vii.2000. ( CZNC). All. Coll. P. Derleth.

Diagnosis. Larvae: A) Dorsal margin of femora with eight to eleven long, clavate setae ( Fig. 31 a); B) Few short spine-like setae between prostheca and mola of right mandible ( Fig. 22 a); C) Right prostheca bifid ( Fig. 22 b); D) Thick maxillary palp, apically pointed, slightly shorter than galea-lacinia ( Fig. 24 ); E) Segment III of labial palp subrectangular and globular, with the distal margin almost straight ( Fig. 25 ); F) Thorax and abdomen with very distinctive dark brown pattern ( Fig. 19 ); G) Hindwing pads absent; H) Spines present on posterior margins of tergites VIII to X; I) Spines present on posterior margins of sternites V to IX; J) Scales lanceolate on surface of abdominal tergites ( Fig. 26 ).

Description. Larvae: Measurements. Length (mm). Body: 3.3–3.9; cerci: 0.8–1.1; terminal filament: 0.8–1.1; antenna: 0.5.

Colouration ( Fig. 19 ): General colouration brown. Head uniformly brown; turbinate eyes brown. Pronotum with M-shaped pattern; mesonotum with complex but consistent pattern, similar to lyre or trident; metanotum with pattern similar to abdominal tergites. Legs light yellow, except for brown stripes at apices of femur and tibia. Abdominal tergites brown with specific pattern composed of two lateral yellowish spots and one smaller, central yellowish spot, except tergites VII and VIII light yellow. Cerci whitish at base and light brown at apex, with one brown stripe every five segments.

Head. Antenna. Scape and pedicel sub-cylindrical.

Labrum ( Fig. 20 ). Length about 0.6 × maximum width. Distal margin rounded and with shallow medial emargination; dorsally with two long, central, stout setae and submedian arc composed of nine stout setae; few short setae scattered on dorsal face. Distal margin with row of multifid (disto-laterally) and bifid (disto-medially) setae. Ventral surface laterally with three short, stout setae.

Hypopharynx ( Fig. 21 ). Lingua slightly longer than superlingua. Distal margin trilobed; covered with short, fine, simple setae. Superlingua subtriangular; fine, simple setae scattered over distal margin.

Right mandible ( Fig. 22 a). Two incisor sets partially fused, inner and outer sets with 3 + 3 denticles respectively, one additional reduced denticle on lateral margin of outer incisor. Prostheca slender, bifurcated ( Fig. 22 b). Margin between prostheca and mola straight with seven spine-like setae. Apex of mola with two setae.

Left mandible ( Fig. 23 ). Two incisor sets almost completely fused, inner and outer set of incisors with 3 + 3 denticles respectively, one additional reduced denticle on lateral margin of distal incisor. Prostheca robust, with denticles and comb-shaped structure. Margin between prostheca and mola almost straight. Triangular process next to mola slender with slightly concave margin, pointing upwards. Denticles of mola not constricted. Tuft of setae at apex of mola absent.

Maxilla ( Fig. 24 ). Apex of lacinia with row of setae with two denti-setae, five long and simple setae and six shorter spine-like setae; outer base of denticles with two simple setae. Maxillary palp 2-segmented, shorter than galealacinia; palp segment II 2.0 × length of segment I; medium, fine, simple setae scattered over surface of maxillary palp; segment II enlarged and apically pointed.

Labium ( Fig. 25 ). Glossae slightly longer than paraglossae; inner margin with five stout setae increasing in length apically; apex with two clavate setae; outer margin with three or four stout setae. Paraglossae: apex with stout setae and one short clavate seta; outer margin with row of about ten long, stout setae. Labial palp with segment I 0.8 × length of segments II & III combined; segment I covered with micropores; segment II slightly projected apically; one row of three spine-like setae ventrally; segment III globular; covered with short and long stout simple setae scattered over ventral surface.

Thorax. Hindwing pads absent.

Legs ( Figs. 31 a, 31b, 32, 33, 34). Femur. Length about 3.5 × maximum width; dorsally with row of 8–11 clavate setae and two clavate setae at apex ( Fig. 31 b); length of setae about 0.3 × maximum width of femur ( Fig. 31 a); ventrally with scattered short stout setae, arc of long and tubular setae present ( Fig. 33 , but not illustrated on Fig. 31 a). Tibia. Dorsally bare except for two small setae at base and one seta at apex; ventrally with one row of about seven short, stout setae and two clavate setae at apex; lateral face with few short, stout setae, tibio-patellar suture present with arc of long and tubular setae. Tarsus. Dorsally with short, minute setae scarce; arc of long, tubular setae; ventrally with one row of about five minute setae and one single longer seta at apex. Tarsal claw with two rows of three or four broad and flattened denticles, apically with two or three furrows ( Figs. 32 , 34 ); subapical setae present but only visible by SEM ( Fig. 34 ).

Abdomen. Tergites. Surface with lanceolate scales and scale bases ( Figs. 26 , 35 ); posterior margins with free lanceolate scales ( Fig. 26 ); spines present on distal margins of segments VIII–X; disto-lateral spines present on segments V–X ( Fig. 27 ).

Sternites. Rows of insertions of setae present on sternites V and VI, poorly visible on adjacent segments; long setae only visible at SEM. Lanceolate scales and scale bases on distal halves of segments I–X; with spines on posterior margins of segments V–IX.

Gills ( Fig. 28 ). Present on segments I–VII. Slender and elongate. Inner and outer margins smooth, only slightly serrated apically. Tracheation well-marked but poorly branched. Gill I about ½ length of gill IV.

Paraproct ( Fig. 29 ). With nine marginal spines, increasing in length. Surface with scale or scale bases. Postero-lateral extension with minute marginal spines.

Caudal filaments. Posterior margins of segments each with two long spines and five or six long, lanceolate scales ( Figs. 30 , 36 ).

Imagos: Unknown.

Etymology. The Indonesian word “ Bintang ” means “Star” in both the astronomical and figurative senses.

Discussion

Bungona (Chopralla) bintang possesses all the characters of the genus Bungona ( Salles et al. 2016) . The presence of two rows of flat denticles on the tarsal claws ( Fig. 32 ) and the peculiar body pattern, especially on the pronotum ( Fig. 19 ), clearly indicate that the species belongs to the subgenus Chopralla .

Including the new species described herein, Chopralla encompasses seven formally described species and Genus No. 2 sp. 1, sensu Müller-Liebenau, 1984. Four named species ( B. (C.) colorata , B. (C.) pusilla , B. (C.) ceylonensis , B. (C.) liebenauae ), and Genus No. 2 sp. 1, possess minute but visible hindwing pads, while B. (C.) fusina , B. (C.) similis and B. (C.) bintang have no hindwing pads ( Müller-Liebenau 1983; Müller-Liebenau 1984; Tong & Dudgeon 2003; Soldán et al. 1987).

The three species without hindwing pads can be distinguished by the number of tergites with spines on the posterior margins: V–X for B. (C.) fusina , IX–X for B. (C.) similis , and VIII–IX for B. (C.) bintang (Table 1). Additional features may be used, especially features of the maxillary palp, which is relatively thin in B. (C.) fusina and B. (C.) similis , while it is thicker in B. (C.) bintang ; B. (C.) fusina apparently does not possess stout setae between the prostheca and mola, while they are present in the two other species ( Müller-Liebenau 1983; Müller- Liebenau 1984; Tong & Dudgeon 2003; Soldán et al. 1987).

Bungona (C.) liebenauae and Genus No. 2 sp. 1 are the unique species of the subgenus, having a right prostheca not bifid and not plumose ( Soldán et al. 1987; Müller-Liebenau 1984). This character clearly indicates that B. (C.) liebenauae and Genus No. 2 sp. 1 have an isolated position within the subgenus ( Soldán et al. 1987).

B. (C.) bintang cannot be included in the identification key of Soldán et al. (1987), as none of the combination of characters in couplets 7–10 correspond (hindwing pads absent—couplet 10; with denticles on tarsal claw and contrasting colour pattern—couplet 7).

Figures

FIGURE 19. Male larvae of Bungona (Chopralla) bintang n. sp., dorsal view.

FIGURES 20 – 25. Larval structures of Bungona (Chopralla) bintang n. sp. (20) Labrum (left: ventral view; right: dorsal view). (21) Hypopharynx. (22 a) Right mandible. (22 b) Right prostheca. (23) Left mandible. (24) Right maxilla. (25) Labium (left: ventral view; right: dorsal view).

FIGURES 26 – 32. Larval structures of Bungona (Chopralla) bintang n. sp. (26) Distal margin of abdominal tergite IV. (27) Disto-lateral spines on segment IV. (28) Gill IV. (29) Paraproct. (30) Segment of cercus. (31 a) Foreleg. (31 b) Apex of forefemur. (32) Fore tarsal claw.

FIGURES 33 – 36. Larval structures of Bungona (Chopralla) bintang n. sp., Scanning Electron Micrographs. (33) Forefemur. (34) Apex of fore tarsal claw. (35) Surface of tergite IV. (35) Detail of cercus.