Nonnullidens kaltenbachi, Sartori & Salles, 2025

Sartori, Michel & Salles, Frederico F., 2025, The Leptophlebiidae of New Guinea (Ephemeroptera, Choroterpinae, Thraulini), ZooKeys 1245, pp. 41-175 : 41-175

Nonnullidens kaltenbachi sp. nov.

Figs 47 , 48

Material examined.

Holotype. • Papua New Guinea, one nymph on slide, Madang Province, Highway near Madang , ford, 80 m, 2–3.XII.2006, 05°24.405'S, 145°38.213'E, Binatang Boys col [PNG 117], GBIFCH 01223143 , some gills and legs in ethanol, GBIFCH 01523465 ( ZSM) . Paratype. • Papua New Guinea, one nymph on slide, GBIFCH 01223144 , Madang Province, Keki, Adalbert Mts , 400 m, 22.XI.2006, 04°43.058'S, 145°24.437'E, Binatang Boys col [PNG 119] ( MZL) .

Diagnosis.

Nymph. Labrum emargination narrow and very deep with flat denticles; femora pale brown with two transverse dark brown bands in middle and at apex; central area of upper surface of femora with very few long and pointed setae; posterior margin of abdominal segments IX with minute denticles; posterolateral expansions on the abdomen present on segments VIII – IX.

Colouration.

Forefemur yellowish, washed with greyish brown in distal half, mid- and hind femur yellowish with a brownish band and in the middle and at apex. Tibia yellowish. Tarsi yellowish.

Description.

Head. Labrum cordiform (Fig. 47 A ). Ratio labrum width / clypeus width 1.03–1.07. Ratio labrum width / insertion width 1.40–1.42. Medial emargination deep, narrow with flat denticles. Proximal row of setae present, simple, shifted to distal margin. Number of setae on proximal row ~ 69–75. Distal row of setae present, simple. Median part of labrum in ventral view with scattered thin setae (Fig. 47 B ). Mandibles. Outer margin with row of setae on distal 1 / 2. Ending of the row near incisor. Right mandible with 4–6 setae below the mola (Fig. 47 C ). Maxillae. Posterior margin of cardo with few hair-like setae, together with one stout and long seta in submarginal position. Proximo-lateral margin of stipes with a bunch of six stout setae increasing in size distally, most distal much longer than the others. Apical-ventral row with 23–26 pectinate setae. Maxillary palp segment II 0.79–0.84 as long as segment I. Maxillary palp segment III 0.61 as long as segment I (Fig. 47 D ). Stout setae on outer margin of segment I absent. Segment II inner margin with one stout seta. Segment II outer margin without or with up to two stout setae. Segment III inner margin without or with up to three stout setae, dorsal surface half covered with setae. Segment III 1.25–1.50 × as long as base width. Labium. Labial palp segment II 0.68–0.86 as long as segment I. Labial palp segment III 0.58–0.66 as long as segment I (Fig. 47 E ). Segment I inner margin with 6–10 stout setae outer margin with 9–13 stout setae. Segment II outer margin with two or three stout setae, dorsal face with two or three stout setae. Segment III 2.71–2.75 × as long as base width. Hypopharynx. Apex of superlingua truncate (Fig. 47 F ).

Thorax. Dorsal margin of femur with a row of long, pointed setae; irregular submarginal row of long, pointed setae as long as those on the dorsal margin; ventral margin with short, pointed setae and an irregular submarginal row of longer and blunt setae (Fig. 48 A – B ); central area of upper surface with very few long, pointed setae (Fig. 48 C ). Fore tibia with several rows of long simple or feathered setae on ventral margin, dorsal margin with few hair-like setae; middle tibia with one row of short, simple, pointed setae, and an irregular submarginal row of long, pointed setae on ventral margin, dorsal margin with numerous hair-like setae; hind tibia with a row of short simple setae on ventral margin and a submarginal row of long, simple, pointed setae, outer margin with long and short pointed setae and numerous hair-like setae. Tarsal claw hooked with three denticles progressively larger apically (Fig. 48 D ).

Abdomen. Gill I with both lamellae. Gills II – VII with dorsal and ventral lamellae, ventral lamella smaller. Gill I with five filaments on dorsal lamella and a single filament on ventral lamella (Fig. 48 E ), gills II – VI with seven or eight filaments on dorsal lamella and three or four filaments on ventral lamella (Fig. 48 F ), gill VII with seven filaments on dorsal lamella and two filaments on ventral lamella (Fig. 48 G ). Posterior margin of terga IX with minute denticles. Posterior margin of terga V – VIII without denticles. Posterolateral projections present on segments VIII – IX.

Derivatio nominis.

This species is dedicated to Dr Thomas Kaltenbach (Naturéum, Lausanne) who revealed the megadiversity of the mayfly genus Labiobaetis in New Guinea.

Figures

Figure 47. Nonnullidens kaltenbachi sp. nov. nymphal mouthparts. A. Labrum, dorsal view; B. Emargination of the labrum; C. Right mandible; D. Maxilla; E. Labium; F. Superlingua of hypopharynx. Scale bars: 200 µm (A, C – E); 50 µm (B); 100 µm (F).

Figure 48. Nonnullidens kaltenbachi sp. nov. thorax and abdomen. A. Fore femur; B. Hind femur; C. Setae on dorsal surface of fore femur; D. Claw; E. Gill I; F. Gill IV; G. Gill VII. Scale bars: 200 µm (A, B); 50 µm (C, D).