Labiobaetis simbuensis, Kaltenbach & Vuataz & Gattolliat, 2023

Kaltenbach, Thomas, Vuataz, Laurent & Gattolliat, Jean-Luc, 2023, New species of Labiobaetis Novikova & Kluge from New Guinea (Ephemeroptera, Baetidae): a never-ending story of diversity, Alpine Entomology 7, pp. 83-134 : 83

publication ID	https://dx.doi.org/10.3897/alpento.7.106089
publication LSID	lsid:zoobank.org:pub:EC4C4A0E-A1F0-4555-B5D4-A4F18AFED1AD
persistent identifier	https://treatment.plazi.org/id/B1E53880-E581-4F58-863F-32CA0910B01A
taxon LSID	lsid:zoobank.org:act:B1E53880-E581-4F58-863F-32CA0910B01A
treatment provided by	Alpine Entomology by Pensoft
scientific name	Labiobaetis simbuensis
status	sp. nov.

Treatment

9. Labiobaetis simbuensis sp. nov.

Figs 26 View Figure 26 , 27 View Figure 27 , 28 View Figure 28 , 29 View Figure 29 , 30 View Figure 30 , 31 View Figure 31 , 38 View Figure 38

Diagnosis.

Larva. Following combination of characters differentiates L. simbuensis sp. nov. from other species of the group Labiobaetis petersorum : A) labrum length 0.6 × maximal width (Fig. 27a View Figure 27 ); B) both mandibles with row of minute denticles on margin between prostheca and mola (Fig. 27d, e, g View Figure 27 h); C) labial palp segment II with small, thumb-like, hooked distomedial protuberance; segment III oblong (Fig. 29d View Figure 29 ); D) paraglossa dorsally with three long, spine-like setae near inner, distal margin (Fig. 29c View Figure 29 ); E) tibia with row of short, spine-like setae on dorsal margin (Fig. 30a, e View Figure 30 ); posterior surface of tibia without scattered, stout setae; F) claw with ca. nine denticles (Fig. 30i View Figure 30 ); G) posterior margin of abdominal tergum IV with triangular or rounded spines, wider than long (Fig. 31c View Figure 31 ).

Description.

Larva (Figs 26 View Figure 26 - 31 View Figure 31 ). Body length 4.7-6.1 mm. Caudalii: broken. Antenna: broken.

Cuticular colouration (Fig. 26a, b View Figure 26 ). Head, thorax and abdomen dorsally light brown. Head, thorax and abdomen ventrally beige. Legs light brown. Caudalii beige.

Hypodermal colouration. Antenna without dark brown dots on flagellum (Fig. 31b View Figure 31 ).

Antenna (Fig. 31a, b View Figure 31 ) with scape and pedicel sub-cylindrical, without distolateral process at scape.

Labrum (Fig. 27a, b View Figure 27 ). Sub-rectangular, length 0.6 × 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. seven long, simple setae. Ventrally with marginal row of setae composed of anterolateral long, feathered setae and medial long, bifid setae.

Right mandible (Fig. 27c, d View Figure 27 ). Incisor and kinetodontium fused. Incisor with three denticles, outer denticle blade-like enlarged; kinetodontium with three denticles, inner margin of innermost denticle with row of thin setae. Prostheca robust, apically denticulate. Margin between prostheca and mola straight, with row of minute denticles. Tuft of setae at apex of mola present.

Left mandible (Fig. 27f-i View Figure 27 ). Incisor and kinetodontium fused. Incisor with three 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, with row of minute 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. 28a View Figure 28 ). Lingua much 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 slightly protruding; lateral margins rounded; fine, long, simple setae along distal margin.

Maxilla (Fig. 28b-d View Figure 28 ). 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. seven long, simple setae. Maxillary palp slightly longer than length of galea-lacinia; 2-segmented; palp segment II 1.5 × as long as segment I, slightly 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. 29a-e View Figure 29 ). Glossa basally broad, narrowing toward apex; much shorter than paraglossa; inner margin with ca. eight spine-like seta; apex with three long, robust, apically pectinate setae; outer margin with ca. four 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 three 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 small, thumb-like, hooked distomedial protuberance; distomedial protuberance 0.3 × 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. 30a-i View Figure 30 ). Ratio of foreleg segments 1.5:1.0:0.6:0.2. Femur. Fore femur very wide, length ca. 2.2 × maximum width, middle and hind femur less wide. Dorsal margin with row of ca. 26 long, curved, spine-like setae, and some short spine-like setae in between; length of setae 0.17 × maximum width of femur. Apex rounded, with medium, spine-like, pointed setae. Apex on posterior side with short, stout, pointed setae on fore and middle leg, absent on hind leg. Stout, lanceolate, pointed setae scattered along ventral margin; femoral patch absent on fore leg, rudimentary on middle leg and hind leg. Tibia. Dorsal margin with row of short, spine-like, pointed 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 without stout setae. Patellatibial suture present on basal 2/3 area. Tarsus. Dorsal margin with one or few short, stout 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. 31c View Figure 31 ). Surface with irregular rows of U-shaped scale bases. Posterior margin of terga: I-II smooth, without spines; III-V with triangular or rounded spines, wider than long; VI-IX with triangular spines, mostly wider than long.

Abdominal sterna. Unknown.

Tergalii (Fig. 31d, e View Figure 31 ). 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.

Paraproct (Fig. 31f View Figure 31 ). Distally not expanded, with ca. 35 stout, marginal spines. Surface scattered with U-shaped scale bases. Cercotractor with numerous small, marginal spines.

Etymology.

Referring to the type locality in Simbu Prov., Papua New Guinea.

Distribution.

Papua New Guinea, Simbu Prov. (Fig. 38a View Figure 38 ).

Biological aspects.

The specimens were collected at an altitude of 2350 m, together with Labiobaetis wilhelmensis Kaltenbach & Gattolliat, 2018 and Labiobaetis gladius Kaltenbach & Gattolliat, 2018.

Type material.

Holotype. PAPUA NEW GUINEA • larva; Simbu Prov., Mt. Wilhelm, Pindaunde Creek, S5, oria. 6; 05°49'57"S, 145°06'08" E; 2350 m; 18.viii.1999; leg. L. Cizek; on slide; GBIFCH00592493; MZL. Paratype. PAPUA NEW GUINEA • 1 larva; same data as holotype; on slide; GBIFCH00975591; MZL.