Papuanatula ( Fijifiliola ) aji, Kaltenbach, 2025

Kaltenbach, Thomas, 2025, Mayflies of the Fiji Islands (Ephemeroptera), ZooKeys 1259, pp. 205-276 : 205-276

Papuanatula ( Fijifiliola) aji sp. nov.

Figs 6 , 7 , 8

Material examined.

Holotype. FIJI • larva; Viti Levu , Ba Prov. , Ba Riv., Qerelevu, near Outback Hotel; 17 ° 37 ' 35 " S, 177 ° 45 ' 04 " E; 20 m; 21. x. 2024; leg. T. Kaltenbach; on slide; GBIFCH 00975845; MZL . Paratypes. • 25 larvae; same data as holotype; 3 on slides; GBIFCH 00975846, GBIFCH 00975847, GBIFCH 01581944; 22 in alcohol; GBIFCH 01581941, GBIFCH 01581942, GBIFCH 01581943; MZL • 32 larvae; Viti Levu , Ba Prov. , Ba Riv. , Qerelevu, near Outback Hotel; 17 ° 37 ' 35 " S, 177 ° 45 ' 04 " E; 20 m; 22. x. 2024; leg. T. Kaltenbach; in alcohol; GBIFCH 01581960, GBIFCH 01581961, GBIFCH 01581962, GBIFCH 01581963, GBIFCH 01582031; MZL • 22 larvae; Viti Levu , Ba Prov., creek, near Outback Hotel; 17 ° 38 ' 12 " S, 177 ° 45 ' 29 " E; 157 m; 25. x. 2024; leg. T. Kaltenbach; in alcohol; GBIFCH 01581912, GBIFCH 01581916, GBIFCH 01581917, GBIFCH 01581918; MZL • 13 larvae; Vanua Levu , Cacaudrove Prov. , tributary to Sekawa Riv., near Nakawaga; 16 ° 39 ' 55 " S, 179 ° 20 ' 03 " E; 32 m; 29. x. 2024; leg. T. Kaltenbach; in alcohol; GBIFCH 01581954, GBIFCH 01582016, GBIFCH 01582017; MZL • 4 larvae; Vanua Levu , Cacaudrove Prov. , Sekawa Riv., many filamentous algae; near Nakawaga; 16 ° 39 ' 54 " S, 179 ° 20 ' 01 " E; 32 m; 29. x. 2024; leg. T. Kaltenbach; in alcohol; GBIFCH 01581909, GBIFCH 01581910; MZL • 14 larvae; Vanua Levu , Cacaudrove Prov. , Seaqaqa Riv., bridge near Saivou village; 16 ° 36 ' 25 " S, 179 ° 08 ' 46 " E; 80 m; 05. xi. 2024; leg. T. Kaltenbach; in alcohol; GBIFCH 01581900, GBIFCH 01581984, GBIFCH 01581985, GBIFCH 01581986, GBIFCH 01581987; MZL • 42 larvae; Viti Levu , Ba Prov. , Sabeto Riv., near Sabeto; 17 ° 43 ' 09 " S, 177 ° 31 ' 21 " E; 30 m; 17. xi. 2024; leg. T. Kaltenbach; in alcohol; GBIFCH 01581971, GBIFCH 01581973, GBIFCH 01581974, GBIFCH 01581975, GBIFCH 01581976, GBIFCH 01581977, GBIFCH 01581978, GBIFCH 01582027, GBIFCH 01582028; MZL • 1 larva; Viti Levu , Ba Prov. , near Abaca village , Savuione Riv., close below Savuione waterfall; 17 ° 40 ' 26 " S, 177 ° 33 ' 06 " E; 690 m; 24. x. 2024; leg. T. Kaltenbach; in alcohol; GBIFCH 01581939; MZL • 16 larvae; Viti Levu , Ba Prov. , near Abaca village, Savuione Riv.; 17 ° 40 ' 07 " S, 177 ° 32 ' 31 " E; 510 m; 24. x. 2024; leg. T. Kaltenbach; 1 on slide; GBIFCH 01581928; 15 in alcohol; GBIFCH 01581924, GBIFCH 01581926, GBIFCH 01581927, GBIFCH 01582018, GBIFCH 01582021, GBIFCH 01582022, GBIFCH 01582023, GBIFCH 01582024, GBIFCH 01582025; MZL .

Diagnosis.

Larva. Following combination of characters distinguishes P. aji sp. nov. from other species of Fijifiliola subgen. nov.: fore protoptera posteromedially with minute spine (Fig. 7 k ); labrum without small process in distomedial emargination; labial palp segment III conical, pointed; abdominal tergum I grey, II, III, VII, and VIII blackish, IV – VI, IX, and X yellowish grey with blackish markings as in Fig. 6 a, b ; femur anteriorly with dark brown hypodermal streak in mediobasal blank (usually developed on fore femur, less on middle femur and absent on hind femur); femur anteriorly with large grey-brown marking in distomedial area, yellowish in subdistal area; paracercus with eight segments.

Description.

Larva (Figs 6 – 8 ). Body length 2.8–3.5 mm, cerci ~ 1.5 × body length.

Colouration (Figs 6 a – c , 8 f ). Head and thorax dorsally dark grey with indistinct pattern, fore protoptera grey with dark grey margins. Abdominal tergum I grey, II, III, VII, and VIII blackish, IV – VI, IX, and X yellowish grey with blackish markings as in Fig. 6 a, b . Thorax and abdomen ventrally grey to reddish grey, sternites VII and VIII darker. Legs grey; femur on anterior side apically, distomedially, and basally dark grey, basal area with large blank and hypodermal streak inside (developed on fore femur, poorly developed on middle femur, absent on hind femur), subdistal area yellowish; femur of all legs on posterior side with brown streak in distomedial area along outer margin. Caudalii grey.

Head. Antenna (Fig. 8 j ). Length ~ 1.5 × head length. As typical for subgenus.

Labrum (Fig. 7 a, b ). Length 0.6 × maximum width. Distomedial emargination without protuberance. Otherwise, as typical for subgenus.

Right mandible (Fig. 7 f ). Margin between prostheca and mola straight, smooth. Otherwise, as typical for subgenus.

Left mandible (Fig. 7 e ). Margin between prostheca and mola straight, smooth. Otherwise, as typical for subgenus.

Hypopharynx and superlinguae (Fig. 7 d ). As typical for subgenus.

Maxilla (Fig. 7 g ). Maxillary palp approx. as long as galea-lacinia; palp segment II ~ 1.4 × longer than segment I. Otherwise, as typical for subgenus.

Labium (Fig. 7 c ). Paraglossa with two spine-like setae on inner, distolateral margin. Labial palp with segment I subequal in length to segments II and III combined. Segment II dorsally with row of five spine-like setae near outer, distolateral margin. Segment III conical, pointed, 0.6 × length of segment II. Otherwise, as typical for subgenus.

Legs (Fig. 8 a – e ). Ratio of leg segments: fore leg 1.0: 1.0: 0.4: 0.2, middle leg 1.1: 1.0: 0.4: 0.2 and hind leg 1.1: 1.0: 0.4: 0.2. Femur. Length ~ 3 × maximum width. Tibia. With one row of short, blunt setae parallel to row of long, fine, simple setae. Claw with one row of 11–14 denticles; one posterior seta. Otherwise, as typical for subgenus.

Abdomen. Terga (Fig. 8 f, g ). Posterior margin of terga: I smooth, without denticles; II – IX with short, triangular, mostly split denticles.

Tergalii (Fig. 8 i ). Elongate oval, rather narrow; tracheation mainly limited to main trunk; margin smooth, with short, fine, simple setae.

Paraproct (Fig. 8 h ). Posterior margin with prolongation, with split denticles in distal part.

Caudalii (Fig. 7 h, i ). Cerci without swimming setae. Paracercus with 7–10 segments.

Pose of subimaginal gonostyli under larval cuticle (Fig. 7 j ). As typical for subgenus. Segment III conical.

Subimago. Unknown.

Imago. Unknown.

Egg. Unknown.

Biological aspects.

By far the most widespread and most frequent Papuanatula species of Fiji. Larvae usually living in run or riffles of medium fast flowing lowland rivers, sometimes in fast flowing, turbulent mountain rivers (Figs 36 b – e , 37 a, b , 38 a – c ). Occurs in more pristine rivers as well as in rivers influenced by human activities.

Etymology.

The species is dedicated to AJ, the owner of the Outback Hotel, where the type locality is located. He and his family provided great support during our stay and on collection excursions.

Distribution.

Fiji: Viti Levu, Vanua Levu (Fig. 39 b ).

Figures

Figure 6. Papuanatula (Fijifiliola) aji sp. nov., larva, habitus. a. dorsal view; b. Lateral view; c. Ventral view. Scale bars: 1 mm.

Figure 7. Papuanatula (Fijifiliola) aji sp. nov., larva. a, b. Labrum; c. Labium; d. Hypopharynx and superlinguae; e. Left mandible; f. Right mandible; g. Maxilla; h. Paracercus; i. Cercus; j. Male mature larva, developing subimaginal gonostylus; k. Fore protoptera, protuberance. Scale bars: 20 µm (a, c – h). 10 µm (b, i – k).

Figure 8. Papuanatula (Fijifiliola) aji sp. nov., larva. a. Hind leg; b. Femur, outer margin; c. Tibia; d. Tarsus, outer margin; e. Tarsus, claw; f. Abdomen; g. Abdominal terga; h. Paraproct; i. Tergalius IV; j. Head. Scale bars: 100 µm (f, j). 50 µm (a); 10 µm (b – e, g – i).

Figure 36. Habitats. a. Overview map; b, c. Ba River near Outback Hotel (locations A, B; lowland river); d. Savuione River, close to beyond the Savuione waterfall, near Abaca village (location C; mountain river); e. Savuione River, downstream of the waterfall, near Abaca village (location C 1; mountain river). For characteristics of locations see Table 3.

Figure 37. Habitats. a. Creek near Outback Hotel (location D 1); b. Sabeto River, near Sabeto (location I; lowland river); c. Biausevu River, near Biausevu (location G); d. Waisila creek, Colo-I-Suva Forest Park (location H). Characteristics of locations see Table 3.

Figure 38. Habitats. a. Tributary to Sekawa River, near Nakawaga (location E; clean lowland river); b. Sekawa River near Nakawaga (location E 1; lowland river, disturbed by human activities; many filamentous green algae); c. Seaqaqa River, bridge near Saivou (location F). Characteristics of locations see Table 3.

Figure 39. Distribution of described species. a. Baetis procul sp. nov. (locations B, I); b. Papuanatula (Fijifiliola) aji sp. nov. (locations A, B, C, C 1, D, E, E 1, F, I); c. Papuanatula (Fijifiliola) aurantica sp. nov. (location G); d. Papuanatula (Fijifiliola) bula sp. nov. (locations D, D 1, G, H); e. Papuanatula (Fijifiliola) claudia sp. nov., Papuanatula (Fijifiliola) flowersi sp. nov. (locations C, C 1); f. Papuanatula (Fijifiliola) crussetae sp. nov. (location C).