Labiobaetis elisae, Kaltenbach, Thomas & Gattolliat, Jean-Luc, 2018

Kaltenbach, Thomas & Gattolliat, Jean-Luc, 2018, The incredible diversity of Labiobaetis Novikova & Kluge in New Guinea revealed by integrative taxonomy (Ephemeroptera, Baetidae), ZooKeys 804, pp. 1-136 : 91-95

27. Labiobaetis elisae sp. n. Figures 50, 51, 63b, 64a

Diagnosis.

Larva. Following combination of characters: A) labrum dorsal submarginal arc of setae composed of one plus 11-13 long, simple setae; B) labrum dorsally with many medium, fine, simple setae, mainly arranged in one band; C) labial palp segment III with emargination at distal margin; D) maxillary palp shorter than galea-lacinia; E) fore femur broad, length ca. 2 × maximum width, dorsal margin with an irregular row of more than 40 curved, spine-like setae and some curved, spine like setae near margin.

Description.

Larva (Figs 50, 51, 63b). Body length 9.6 mm.

Colouration. Head, thorax and abdomen dorsally brown, abdominal terga I and X lighter. Head and thorax with bright median, dorsal suture, forewing pads with bright striation. Thorax and abdomen ventrally light brown, femur with brown dorsal margin, legs otherwise light brown, caudal filaments light brown.

Antenna with scape and pedicel sub-cylindrical, without distolateral process at scape; flagellum with broad, apically blunt spines and fine, simple setae on apex of each segment.

Labrum (Fig. 50a). Rectangular, length 0.6 × maximum width. Distal margin with medial emargination and a small process. Dorsally with many medium to long, fine, simple setae, mainly arranged in one band; submarginal arc of setae composed of one plus 11-13 long, simple setae. Lateral margin with few long, fine, simple setae. Ventrally with marginal row of setae composed of lateral and anterolateral long, feathered setae and medial long, bifid setae; ventral surface with eight short, spine-like setae near lateral and anterolateral margin.

Right mandible (Fig. 50b, c). Incisors fused. Outer and inner sets of denticles with 4 + 3 denticles plus one small intermediate denticle. Inner margin of innermost denticle with a row of thin setae. Prostheca robust, apically denticulate. Margin between prostheca and mola slightly convex. Tuft of setae at apex of mola present.

Left mandible (Fig. 50d, e). Incisors fused. Outer and inner sets of denticles with 3 + 4 denticles. Prostheca robust, apically with small denticles and comb-shape structure. Margin between prostheca and mola slightly convex, with minute denticles toward subtriangular process. Subtriangular process long and slender, above level of area between prostheca and mola. Denticles of mola apically constricted. Tuft of setae at apex of mola present.

Both mandibles with lateral margins slightly convex. Basal half with fine, simple setae scattered over dorsal surface.

Hypopharynx (Fig. 50f). Lingua longer than superlingua. Lingua about as broad as long; medial tuft of stout setae present; distal half not expanded. Superlingua rounded; lateral margin rounded; fine, long, simple setae along distal margin and short, simple setae in distal part.

Maxilla (Fig. 50g). Galea-lacinia with two simple, robust apical setae under crown. 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 spine-like seta and six long, simple setae. Maxillary palp shorter than length of galea-lacinia; two segmented. Palp segment II somewhat shorter than segment I. Setae on maxillary palp fine and simple, scattered over surface of segments I and II. Palp segment III about as long as segment II. Apex of last segment rounded, without excavation at inner distolateral margin.

Labium (Fig. 50h). Glossa basally broad, narrowing toward apex; shorter than paraglossa; inner margin with six spine-like setae increasing in length distally; apex with three long, robust, pectinate setae and one short, robust seta; outer margin with six long spine-like setae increasing in length distally; ventral surface with short, simple setae. Paraglossa sub-rectangular, curved inward; apex rounded; with three rows of long, robust, apically pectinate setae; dorsally with nine medium, simple setae; ventrally with three long, spine-like setae near inner margin. Labial palp with segment I 0.8 × length of segments II and III combined. Segment I dorsally covered with micropores and ventrally with fine, simple setae along margins. Segment II with a short, thumb-like distomedial protuberance; distomedial protuberance 0.2 × width of base of segment III; inner and outer margin both with short, fine, simple setae; dorsally with row of five long, spine-like, simple setae. Segment III conical; apex with emargination; ventrally covered with short, fine, simple setae.

Hind wing pads absent.

Foreleg (Fig. 51 a–c). Ratio of foreleg segments 1.2:1.0:0.5:0.2. Femur. Length ca. 2 × maximum width. Dorsal margin with an irregular row of more than 40 curved, spine-like setae and some curved, spine-like setae and fine, simple setae near margin; length of setae 0.1 × maximum width of femur. Apex rounded; with one pair of curved, spine-like setae and many short, stout, apically rounded setae. Many stout, lanceolate, setae and a few fine, simple setae along ventral margin; femoral patch poorly developed. Tibia. Dorsal margin with a row of fine, simple setae and a row of stout, lanceolate setae along margin. Ventral margin with a row of short, curved, spine-like setae and a tuft of long, fine, simple setae on apex. Anterior surface scattered with stout, lanceolate, apically rounded setae and fine, simple setae. Tibio-patellar suture present on basal 2/3. Tarsus. Dorsal margin with a row of short, spine-like setae and a row of long, fine, simple setae on and near margin, especially on apex. Ventral margin with a row of curved, spine-like setae. Tarsal claw with one row of 11-12 denticles; tapering distally; with 4-6 stripes; subapical setae absent.

Tergum (Fig. 51d). Surface with irregular rows of U-shaped scale bases and scattered fine, simple setae, scales short and apically rounded. Posterior margin of tergum IV with rounded spines, wider than long.

Gills (Fig. 51e). Present on segments II - VII. Margin with small denticles intercalating long, fine, simple setae. Tracheae extending from main trunk to inner and outer margins. Gill IV as long as length of segments V and 1/2 VI combined. Gill VII little longer than length of segment VIII.

Paraproct (Fig. 51f). Distally expanded, with many marginal, stout spines. Surface with U-shaped scale bases and scattered fine, simple setae. Postero-lateral extension (cercotractor) with small marginal spines.

Etymology.

Dedicated to Elisa Gattolliat, the daughter of one of the authors.

Distribution.

New Guinea.

Biological aspects.

The specimens were collected in altitudes of 1200 m and 1400 m a.s.l.

Type-material.

Holotype. Nymph (on slide, GBIFCH 00465219), Papua New Guinea, Western Highlands, Kundum, 1400 m, 03 Mar 2007, 05°16.10'S, 144°27.87'E, Kinibel (PNG142). Deposited in ZSM. Paratypes. 31 nymphs (1 on slide, GBIFCH 00465220, 20 in alcohol, GBIFCH 00515221; 10 in alcohol, GBIFCH 00515222, deposited in ZSM), same data as holotype; 1 nymph (on slide, GBIFCH 00465221, remaining parts in alcohol, GBIFCH 00515287, deposited in MZL), Papua New Guinea, Madang, Simbai area, 1200 m, 10 Mar 2007, 05°13.39'S, 144°37.29'E, Kinibel (PNG 152); 1 nymph (on slide, GBIFCH 00465231, deposited in MZL), Papua New Guinea, Eastern Highlands, Bena, 1393 m, 20 Oct 2002, 06°11.02'S, 145°26.41'E, grassland river, K. Sagata leg.