Papuanatula (Papuanatula) epibessa Kaltenbach, Kluge & Gattolliat, 2025, sp. nov.
Creators: name: Kaltenbach, Thomas
name: Kluge, Nikita J.
name: Gattolliat, Jean-Luc
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Ephemeroptera
Baetidae
Papuanatula
Papuanatula epibessa

description: Papuanatula (Papuanatula) epibessa sp. nov.
Figs 48, 49, 50, 51, 52, 53, 54
Etymology.
The species name epibessa refers to the morphological similarity with P. bessa.
Material examined.
Holotype. Papua New Guinea • larva; Simbu Prov., Mt. Wilhelm, Pindaunde Creek, in forest, S 3 (oria 4); 05°49'S, 145°04'30"E; 2900 m; 18. viii. 1999; leg. L. Čížek; on slide; GBIFCH 01221766; MZL. Paratypes. 31 larvae; same data as holotype; in alcohol; GBIFCH 00976020, GBIFCH 00976121; MZL • 93 larvae; Simbu Prov., Mt. Wilhelm, Pindaunde Creek, near fish farm, S 4 (oria 5); 05°49'02"S, 145°05'16"E; 2600 m; 18. viii. 1999; leg. L. Čížek; 3 on slides; GBIFCH 01221759, GBIFCH 01221761, GBIFCH 01221767; MZL; 90 in alcohol; GBIFCH 00976021, GBIFCH 00976023, GBIFCH 00976024, GBIFCH 00976126; MZL • 18 larvae; Simbu Prov., Mt. Wilhelm, Pindaunde Creek, S 2 (oria 2); 05°48'03"S, 145°04'09"E; 3210 m; 17. viii. 1999; leg. L. Čížek; 1 on slide; GBIFCH 01221762; 17 in alcohol; GBIFCH 00976124; MZL.
Diagnosis.
Larva. The following combination of characters distinguishes P. epibessa sp. nov. from other species of Papuanatula s. str.: body dorsally with irregular row of long, fine, simple setae along midline; metanotum and abdominal terga I – III with medioposterior, broad, paired humps, poorly developed on terga I – III; femur yellow brown, basally with wedge-shaped blank; paracercus with 6–8 segments; claw with 1–3 posterior setae.
Description.
Larva (Figs 48 – 54). Body length 4.1–5.5 mm, cerci much longer than body length (~ 1.7 ×).
Cuticular coloration (Figs 48 a – c, 49 a) Head, thorax and abdomen dorsally yellow brown to brown, thorax with complex markings. Abdominal terga II – V with brown markings along anterior margin, tergum III additionally with mediolateral, brown markings. Femur yellow brown, basally with wedge-shaped blank. Tibia pale yellow brown; tarsus yellow brown. Cerci pale yellow brown.
Hypodermal coloration (Figs 48 a, 49 a) Abdominal terga with narrow, dark brown, transverse bands along posterior margin.
Head. Dorsally with irregular row of long, fine, simple setae along midline. Antenna (Fig. 51 e). Length ~ 1.5 × head length. Developing turbinate eyes in last instar male larva (Fig. 51 e) rather small, ovoid, with big distance to each other. Labrum (Fig. 50 a, b). Length 0.5 × maximum width, laterally convex. Dorsal, sub-marginal arc with ~ 35 feathered setae. Right mandible (Fig. 50 d, e). Margin between prostheca and mola with few denticles close to prostheca. Otherwise, as typical for subgenus. Left mandible (Fig. 50 f, g). Margin between prostheca and mola smooth, with few denticles close to prostheca. Otherwise, as typical for subgenus. Hypopharynx (Fig. 50 c). As typical for genus. Maxilla (Fig. 51 c, d). Maxillary palp subequal in length to galea-lacinia; palp segment II approximately as long as segment I. Otherwise, as typical for genus. Labium (Fig. 51 a, b). As typical for the genus. Paraglossa dorsally with 2 spine-like setae near inner, distolateral margin. Labial palp with segment I approximately as long as segments II and III combined. Segment II with minute distomedial protuberance, dorsally with row of five or six spine-like setae near outer, distolateral margin. Segment III conical, pointed; 0.8 × length of segment II; inner dorsal margin with few feathered setae.
Thorax. Sterna. With small protuberances on sides of prosternum and close to openings of mesothoracic and metathoracic sternal apodemes (as Fig. 108 a). Terga (Figs 48 b, 53 a) with irregular row of long, fine, simple setae along midline. Metanotum with medioposterior broad, paired humps, without hind protoptera or their vestiges. Legs (Fig. 52 a – h). Ratio of leg segments: fore leg 0.8: 1.0: 0.3: 0.1, middle leg 0.9: 1.0: 0.3: 0.1 and hind leg 1.0: 1.0: 0.3: 0.1. Femur. Length ~ 4 × maximum width. Posterior side of apex with row of robust setae (contrary to fine, simple setae as it is usually the case in Papuanatula s. str.). Tarsus. Inner margin distally sometimes with two long setae (Fig. 52 g). Claw with one row of 6–8 (9) denticles and 1–3 posterior setae.
Abdomen. Terga (Figs 48 b, 53 a, b, 54 a, b) with irregular row of long, fine, simple setae along midline. Terga I – III with poorly developed, medioposterior, broad, paired humps. Terga II – IV protruding slightly medially on posterior margin. Posterior margin of terga: I smooth, without denticles; II – IX with triangular, apically rounded denticles, partly with minute, pointed denticles in between. Surface with scattered small, ovoid, striated scales with slightly serrate margin. Tergalii (Fig. 53 e, f). Ovoid, tracheation poorly developed or absent; margins smooth, with short, fine, simple setae. Paraproct (Fig. 53 g). Posterior margin with prolongation and row of minute denticles. Caudalii (Fig. 53 c, d). Cerci in middle part with one to maximally five swimming setae per segment, initially increasing and then again decreasing toward distal part; sometimes total loss or maximally one swimming seta per segment. Paracercus with 6–8 segments.
Pose of subimaginal gonostyli under larval cuticle. Unknown.
Subimago. Unknown.
Imago. Unknown.
Egg. Unknown.
Distribution.
New Guinea (Fig. 146).
description: Published as part of Kaltenbach, Thomas, Kluge, Nikita J. & Gattolliat, Jean-Luc, 2025, Redescription of Papuanatula Lugo-Ortiz & McCafferty (Ephemeroptera, Baetidae), with description of a new subgenus and 20 new species, pp. 159-347 in ZooKeys 1227 on pages 159-347, DOI: 10.3897/zookeys.1227.138100