Labiobaetis papuaensis, 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 : 26-28

7. Labiobaetis papuaensis sp. n. Figures 14, 15, 59b, 64a

Diagnosis.

Larva. Following combination of characters: A) labrum dorsal submarginal arc of setae composed of 14-17 feathered setae, B) labial palp segment II with a large, lobed distomedial protuberance; C) labial palp segment III slightly pentagonal, apically slightly pointed; D) fore femur very slender, length ca. 5 × maximum width, dorsal margin with a row of ca. 13 robust, slightly spatulate, apically blunt setae; E) tibia dorsal margin with a row of stout, lanceolate, apically rounded setae.

Description.

Larva (Figs 14, 15, 59b). Body length 5.4 mm.

Colouration. Head, thorax and abdomen dorsally brown, with bright pattern as in Fig. 59b. Head and thorax with bright median, dorsal suture, forewing pads with bright striation. Head, thorax and abdomen ventrally light brown, legs and caudal filaments light brown, femur dorsal margin brown.

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

Labrum (Fig. 14a, b). 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 14-17 long, feathered setae. Ventrally with marginal row of setae composed of lateral and anterolateral long, feathered setae and medial long, bifid, pectinate setae; ventral surface with eight short, spine-like setae near lateral and anterolateral margin.

Right mandible (Fig. 14c, d). 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. 14e, f). Incisors fused. Outer and inner sets of denticles with 4 + 4 denticles. Prostheca robust, apically denticulate. Margin between prostheca and mola straight, with minute denticles towards 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 almost straight. Basal half with fine, simple setae scattered over dorsal surface.

Hypopharynx . Unknown.

Maxilla (Fig. 14g). 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 four long, simple setae. Maxillary palp about as long as length of galea-lacinia; two segmented. Palp segment II 1.8 × length of segment I. Setae on maxillary palp fine and simple, scattered over surface of segment II. Apex of last segment rounded, with an excavation at inner distolateral margin.

Labium (Fig. 14h). Glossa basally broad, narrowing toward apex; shorter than paraglossa; inner margin with nine spine-like setae increasing in length distally; apex with three long, robust, pectinate setae; outer margin with seven spine-like setae increasing in length distally; ventral surface with short, fine, simple setae. Paraglossa sub-rectangular, curved inward; apex rounded; with three rows of long, robust, apically pectinate setae; dorsally with row of six medium, simple setae; ventrally with three long, spine-like setae near inner margin. Labial palp with segment I 0.7 × length of segments II and III com bined. Segment I covered with micropores dorsally and ventrally with fine, simple setae along margins. Segment II with a large, lobed distomedial protuberance; distomedial protuberance 0.6 × width of base of segment III; inner margin with few fine, simple setae; outer margin with few short, fine, simple setae; dorsally with a row of three long, spine-like setae. Segment III slightly pentagonal; 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. 15 a–d). Ratio of foreleg segments 1.1:1.0:0.4:0.1. Femur. Length ca. 5 × maximum width. Dorsal margin with a row of ca. nine robust, slightly spatulate, apically rounded setae and four spine-like, apically pointed setae on basal area length of setae 0.17 × maximum width of femur. Apex rounded; with one pair of robust, slightly spatulate, apically rounded setae and some short, stout, apically rounded setae. Many stout, broad lanceolate, apically rounded setae along ventral margin; femoral patch absent. Tibia. Dorsal margin with a row of stout, broad lanceolate, apically rounded setae. Ventral margin with a row of curved, spine-like setae and some longer, spine-like, bipectinate setae and a tuft of long, fine, simple setae on apex. Anterior surface scattered with stout, lanceolate setae. Tibio-patellar suture present on basal 1/3. Tarsus. Dorsal margin bare with a tuft of long, fine, simple setae on apex (Fig. 15d). Ventral margin with a row of curved, spine-like setae. Tarsal claw with one row of 12-13 denticles; distally pointed; with four stripes; subapical setae absent.

Tergum (Fig. 15e). Surface with irregular rows of U-shaped scale bases and scattered micropores. Posterior margin of tergum IV with rounded or triangular spines, wider than long.

Gills (Fig. 15f). Present on segments II–VII. Margin with small denticles and long, fine, simple setae. Tracheae extending from main trunk to inner and outer margins. Gill IV as long as length of segments V and VI combined. Gill VII as long as length of segments VIII, IX and 1/2 X combined.

Paraproct (Fig. 15g). Distally expanded, with many marginal, stout spines. Surface with U-shaped scale bases and scattered fine, simple setae and micropores. Postero-lateral extension (cercotractor) with small marginal spines.

Etymology.

Refers to the type locality in the Papua Province of Indonesia.

Distribution.

New Guinea.

Biological aspects.

The specimens were collected at an altitude of 774 m a.s.l.

Type-material.

Holotype. Nymph (on slide, GBIFCH 00465170), Indonesia, Papua, Road Nabire-Enarotali KM 55, 774 m, 22 Oct 2011, 03°29.80'S, 135°43.89'E, Balke (PAP09). Temporary deposited in MZL before definitely housed in MZB. Paratype. 1 nymph (on slide, GBIFCH 00465171, deposited in MZL), same data as holotype.