Labiobaetis pindaundensis, 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 : 100-103

30. Labiobaetis pindaundensis sp. n. Figures 54, 55, 63c, 65b

Diagnosis.

Larva. Following combinations of characters: A) labrum dorsal submarginal arc of setae composed of one plus 10-12 long, simple setae; B) maxillary palp 1.6 × as long as length of galea-lacinia; C) labial palp segment III conical, slightly pointed; D) labial palp segment II with a large, lobed distomedial protuberance; E) fore femur slender, length ca. 4 × maximum width, dorsal margin with a row of ca. 27 curved, spine-like setae and with stout, pointed setae near margin.

Description.

Larva (Figs 54, 55, 63c). Body length 7.5 mm; antenna approximately 2.5 × as long as head length.

Colouration. Head, thorax and abdomen dorsally brown, head and thorax with bright median, dorsal suture, forewing pads with bright striation. Head, thorax and abdomen ventrally light brown, legs colourless, caudal filaments light brown.

Antenna with scape and pedicel sub-cylindrical, without distolateral process at scape; flagellum with lanceolate spines on apex of each segment.

Labrum (Fig. 54a). Rectangular, length 0.7 × maximum width. Distal margin with medial emargination and a small process. Dorsally with medium, fine, simple setae scattered over surface; submarginal arc of setae composed of one plus 10-12 long, simple setae. Ventrally with marginal row of setae composed of lateral and anterolateral long, feathered setae and medial long, bifid, pectinate setae; ventral surface with nine short, spine-like setae near lateral and anterolateral margin.

Right mandible (Fig. 54b, c). Incisors fused. Outer and inner sets of denticles with 4 + 3 denticles. 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. 54d, e). Incisors fused. Outer and inner sets of denticles with 4 + 3 denticles. Prostheca robust, apically with small denticles and comb-shape structure. Margin between prostheca and mola slightly convex. 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 almost straight. Basal half with fine, simple setae scattered over dorsal surface.

Hypopharynx (Fig. 54f). Lingua shorter than superlingua. Lingua longer than broad; medial tuft of stout setae present; distal half laterally expanded. Superlingua rounded; lateral margin rounded; fine, long, simple setae along distal margin.

Maxilla (Fig. 54g). 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 bipectinate, spine-like seta and seven long, simple setae. Maxillary palp 1.6 × as long as length of galea-lacinia; two segmented. Palp segment II 1.9 × length of segment I. Setae on maxillary palp fine and simple, scattered over surface of segments I and II. Apex of last segment slightly pointed, without excavation at inner distolateral margin.

Labium (Fig. 54h). Glossa basally broad, narrowing toward apex; shorter than paraglossa; inner margin with ten spine-like setae increasing in length distally; apex with three long, robust setae; outer margin with ten long, spine-like setae; ventral surface with fine, simple setae. Paraglossa sub-rectangular, curved inward; apex rounded; with three rows of long, robust, apically pectinate setae; dorsally with ten medium, simple setae; ventrally with six long, spine-like setae near inner margin. Labial palp with segment I 0.7 × length of segments II and III combined. Segment I covered with short, fine, simple setae ventrally and micropores dorsally. Segment II with a large, lobed distomedial protuberance; distomedial protuberance 0.8 × 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 slightly pointed; length 1.2 × width; ventrally covered with medium spine-like, simple setae and short, fine, simple setae.

Hind wing pads absent.

Foreleg (Fig. 55a, b). Ratio of foreleg segments 1.4:1.0:0.8:0.2. Femur. Length ca. 4 × maximum width. Dorsal margin with a row of ca. 27 curved, short, spine-like setae and with stout, pointed setae near margin; length of setae 0.14 × maximum width of femur. Apex rounded; with two pairs of curved, spine-like setae and many short, stout, pointed 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 short, curved, spine-like setae and long, fine, simple setae. Ventral margin with a row of curved, spine-like setae, apically longer, dense and bipectinate and with a tuft of long, fine, simple setae. Anterior surface scattered with many stout, lanceolate setae, partly bipectinate (difficult to see). Tibio-patellar suture present on basal 1/2. Tarsus. Dorsal margin with a row of short, curved, spine-like setae. Ventral margin with a row of curved, spine-like setae. Tarsal claw with one row of 13-14 denticles; distally pointed; with 5-6 stripes; subapical setae absent.

Tergum (Fig. 55c). 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. 55d). 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, VI and 1/2 VII combined. Gill VII as long as length of segments VIII and IX combined.

Paraproct (Fig. 55e). Distally slightly 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.

Refers to Pindaunde Creek in Papua New Guinea, where the species has been collected.

Distribution.

New Guinea.

Biological aspects.

The specimens were collected at altitudes of 1700 m, 2600 m and 2900 m a.s.l., partly in forest.

Type-material.

Holotype. Nymph (on slide, GBIFCH 00465222), Papua New Guinea, Simbu Prov., 05°49.00'S, 145°04.50'E, (GPS), Mt. Wilhelm, Pindaunde Creek, 2900 m a.s.l. (in forest), S3 (oria.4),18 Aug 1999, leg. L. Čížek. Deposited in MZL. Paratypes. 13 nymphs (1 on slide, GBIFCH 00465223, 8 in alcohol, GBIFCH 00515236, GBIFCH 00508125, deposited in MZL; 4 in alcohol, GBIFCH 00515237, deposited in ZSM), same data as holotype; 2 nymphs (1 on slide, GBIFCH 00465224, 1 in alcohol, GBIFCH 00515238, deposited in MZL), Papua New Guinea, Simbu Prov., 05°49.03'S, 145°05.27'E, Mt. Wilhelm, Pindaunde Creek, 2600 m a.s.l. (near fish farm), (9181 ft GPS), S4 (oria.5), 18 Aug 1999, L. Čížek leg.

Additional material.

10 nymphs (1 on slide, GBIFCH 00465225, 9 in alcohol, GBIFCH 00515278, deposited in MZL), Papua New Guinea, Central, Woitape, 1700 m, 01.2008, 08°31.29'S, 147°13.68'E, Posman (PNG 166).