New species of Labiobaetis Novikova & Kluge from New Guinea (Ephemeroptera, Baetidae): a never-ending story of diversity Author Kaltenbach, Thomas https://orcid.org/0000-0001-8052-0388 Museum cantonal des Sciences Naturelles, Departement de zoologie, Palais de Rumine, Place Riponne 6, CH- 1005 Lausanne, Switzerland & University of Lausanne (UNIL), Department of Ecology and Evolution, CH- 1015 Lausanne, Switzerland thomas.kaltenbach@bluewin.ch Author Vuataz, Laurent https://orcid.org/0000-0001-9193-8683 Museum cantonal des Sciences Naturelles, Departement de zoologie, Palais de Rumine, Place Riponne 6, CH- 1005 Lausanne, Switzerland & University of Lausanne (UNIL), Department of Ecology and Evolution, CH- 1015 Lausanne, Switzerland Author Gattolliat, Jean-Luc https://orcid.org/0000-0001-5873-5083 Museum cantonal des Sciences Naturelles, Departement de zoologie, Palais de Rumine, Place Riponne 6, CH- 1005 Lausanne, Switzerland & University of Lausanne (UNIL), Department of Ecology and Evolution, CH- 1015 Lausanne, Switzerland text Alpine Entomology 2023 2023-07-07 7 83 134 http://dx.doi.org/10.3897/alpento.7.106089 journal article http://dx.doi.org/10.3897/alpento.7.106089 2535-0889-7-83 EC4C4A0EA1F04555B5D4A4F18AFED1AD 1413FD1E0A7D5CB9A8D543F2604617E5 8. Labiobaetis nabire sp. nov. Figs 20 , 21 , 22 , 23 , 24 , 25 , 38 Diagnosis. Larva. Following combination of characters differentiates L. nabire sp. nov. from other species of the group Labiobaetis petersorum : A) labrum length 0.6 x maximal width (Fig. 21a ); B) both mandibles with smooth margin between prostheca and mola (Fig. 21c, e ); C) labial palp segment II with thumb-like, distomedial protuberance, distal margin of protuberance slightly concave; segment III oblong (Fig. 23d ); D) paraglossa dorsally with two long, spine-like setae near inner, distal margin (Fig. 23c ); E) tibia with row of short, stout, apically rounded setae on dorsal margin (Fig. 24e ); posterior surface without scattered, stout setae; F) claw with ca. nine denticles (Fig. 24g ); G) posterior margin of abdominal tergum IV with triangular spines, mostly slightly wider than long (Fig. 25c ); H) legs with hypodermal, oblong, orange-brown spot medially on posterior side of femur (Fig. 20a ). Description. Larva (Figs 20 - 25 ). Body length 6.3-7.2 mm. Cerci: nearly as long as body length. Paracercus: ca. 0.5 x cerci length. Antenna: approx. 2.5 x as long as head length. Figure 20. Labiobaetis nabire sp. nov., larva habitus: a. Dorsal view; b. Ventral view. Scale bars 1 mm. Figure 21. Labiobaetis nabire sp. nov., larva morphology: a. Labrum; b. Section of labrum, dorsal focus; c, d. Right mandible; e, f. Left mandible. Scale bars: 50 µm . Figure 22. Labiobaetis nabire sp. nov., larva morphology: a. Hypopharynx and superlinguae; b. Maxilla; c. Maxillary palp; d, e. Sections of maxilla. Scale bars: 50 µm . Figure 23. Labiobaetis nabire sp. nov., larva morphology: a. Labium; b. Glossa and paraglossa, ventral focus; c. Section of paraglossa, dorsal focus; d. Labial palp, ventral focus; e. Section of labial palp, dorsal focus. Scale bar: 50 µm . Figure 24. Labiobaetis nabire sp. nov., larva morphology: a. Fore leg; b. Fore femur, dorsal margin; c. Fore femur, ventral margin; d. Fore femur, apex, posterior side; e. Fore tibia, dorsal margin; f. Fore tarsus, dorsal margin; g. Fore claw; h. Tip of fore claw. Scale bars: 50 µm . Figure 25. Labiobaetis nabire sp. nov., larva morphology: a. Base of antenna; b. Antenna; c. Abdominal tergum IV; d. Tergalius IV; e. Anal margin of tergalius IV; f. Paraproct. Scale bars: 50 µm . Cuticular colouration (Fig. 20a, b ). Head, thorax and abdomen dorsally grey-brown, with pattern as in Fig. 20a . Abdominal terga VI, IX and partly X brighter; I-IX laterally with bright marks. Thorax and abdomen ventrally off-white. Legs with different shades of grey and brown as in Fig. 20b ; femur with elongate proxomedial and distodorsal blanks. Caudalii grey-brown. Hypodermal colouration . Antenna with dark brown dots in middle part of flagellum (Fig. 25b ). Abdominal intersegmental membranes in distal part of abdomen with dark brown anterior margins (Fig. 20a ). Femora on posterior side with medial, oblong, orange-brown spots (Fig. 20a ). Antenna (Fig. 25a, b ) with scape and pedicel sub-cylindrical, without distolateral process at scape. Labrum (Fig. 21a, b ). Sub-rectangular, length 0.6 x maximum width. Distal margin with medial emargination and small process. Dorsally with medium, fine, simple setae scattered over surface; submarginal arc of setae composed of ca. eight long, simple setae. Ventrally with marginal row of setae composed of anterolateral long, feathered setae and medial long, bifid setae. Right mandible (Fig. 21c, d ). Incisor and kinetodontium fused. Incisor with three denticles, outer denticle blade-like enlarged; kinetodontium with four denticles, inner margin of innermost denticle with row of thin setae. Prostheca robust, apically denticulate. Margin between prostheca and mola straight, smooth, without denticles. Tuft of setae at apex of mola present. Left mandible (Fig. 21e, f ). Incisor and kinetodontium fused. Incisor with four denticles, outer denticle blade-like enlarged; kinetodontium with three denticles. Prostheca robust, apicolaterally with small denticles and comb-shaped structure. Margin between prostheca and mola straight, smooth, without denticles. Subtriangular process above level of area between prostheca and mola. Tuft of setae at apex of mola present. Both mandibles with lateral margins almost straight. Hypopharynx and superlinguae (Fig. 22a ). Lingua longer than superlinguae. Lingua longer than broad; medial tuft of stout setae well developed, distolaterally with two additional tufts of setae; distal half laterally not expanded. Superlinguae distolaterally protruding; lateral margins rounded; fine, long, simple setae along distal margin. Maxilla (Fig. 22b-e ). Galea-lacinia ventrally with two simple, apical setae below canines. Inner dorsal row of setae with three denti-setae, distal denti-seta tooth-like, middle and proximal denti-setae slender, bifid and pectinate. Medially with one feathered spine-like seta and ca. eight long, simple setae. Maxillary palp approx. as long as length of galea-lacinia; 2-segmented; palp segment II approx. as long as segment I, and narrower; setae on maxillary palp fine, simple, scattered over surface of segments I and II; apex of last segment without distolateral excavation, apically pointed, constricted. Labium (Fig. 23a-e ). Glossa basally broad, narrowing toward apex; much shorter than paraglossa; inner margin with ca. seven spine-like seta; apex with three long, robust, apically pectinate setae; outer margin with ca. six spine-like setae; ventral surface with fine, simple, scattered setae. Paraglossa sub-rectangular, slightly curved inward; apex rounded; with three rows of long, robust, distally pectinate setae in apical area; dorsally with two long, spine-like setae near inner margin. Labial palp with segment I approx. as long as length of segments II and III combined. Segment II with thumb-like, distomedial protuberance; distal margin of protuberance slightly concave; distomedial protuberance 0.5 x width of base of segment III; ventral surface with short, fine, simple setae; dorsally with row of ca. five spine-like setae near outer margin. Segment III oblong; length approx. width; ventrally covered with short, spine-like, simple setae and short, fine, simple setae. Hind protoptera absent. Legs (Fig. 24a-h ). Ratio of foreleg segments 1.3:1.0:0.6:0.2. Femur . Fore femur length ca. 2.5 x maximum width, middle and hind femur slightly less wide. Dorsal margin with row of ca. 25 short to medium, curved, spine-like, apically rounded setae; length of setae 0.13 x maximum width of femur. Apex rounded, with many short, stout, apically rounded setae. Apex on posterior side with short, stout, apically rounded setae on fore and middle leg, absent on hind leg. Stout, lanceolate, pointed setae scattered along ventral margin; femoral patch rudimentary on fore and middle leg, reduced on hind leg. Tibia . Dorsal margin with row of short, stout, apically rounded setae. Ventral margin with row of short, curved, spine-like setae, on apex a tuft of fine, simple setae. Anterior surface with short, stout, lanceolate, pointed setae along patellatibial suture. Posterior surface with very few stout setae. Patellatibial suture present on basal 2/3 area. Tarsus . Dorsal margin with row of short, apically rounded setae. Ventral margin with row of curved, spine-like setae increasing in length distally. Claw with one row of ca. nine denticles; distally pointed; with long, fine, transparent subapical seta on posterior side. Abdominal terga (Fig. 25c ). Surface with irregular rows of U-shaped scale bases. Posterior margin of terga: I smooth, without spines; II-III with poorly developed spines; IV-V with triangular spines, mostly slightly wider than long; VI-IX with triangular spines, longer than wide. Abdominal sterna . Posterior margin of sterna: I-VI smooth, without spines; VII-IX with small, triangular spines. Tergalii (Fig. 25d, e ). Present on segments II-VII. Margin with small denticles intercalating fine, simple setae. Anal margin with both short and long, fine setae. Tracheae extending from main trunk to inner and outer margins. Tergalius IV as long as length of segments V, VI and 1/3 VII combined. Tergalius VII as long as length of segments VIII and 1/3 IX combined. Paraproct (Fig. 25f ). Distally not expanded, with ca. 33 stout, marginal spines. Surface scattered with U-shaped scale bases. Cercotractor with numerous small, marginal spines. Etymology. Referring to the type locality in Nabire Regency, Central Papua Prov, Indonesia. Distribution. Indonesia, Central Papua Prov. (Fig. 38a ). Biological aspects. The specimens were collected at an altitude of 774 m, together with Labiobaetis papuaensis Kaltenbach & Gattolliat, 2018. Type material. Holotype . INDONESIA • larva; Papua Prov., Road Nabire-Enarotali KM 55; 03°29'48"S , 135°43'53"E ; 774 m; 22.x.2011; leg. M. Balke; (PAP09); on slide; GBIFCH00980888; ZSM. Paratypes . INDONESIA • 11 larvae; same data as holotype; 3 on slides; GBIFCH00592568, GBIFCH00592569, GBIFCH00980889; MZL; 8 in alcohol; GBIFCH00975588, GBIFCH00975615; MZL.