Labiobaetis sumbensis, Kaltenbach, Thomas & Gattolliat, Jean-Luc, 2019

Kaltenbach, Thomas & Gattolliat, Jean-Luc, 2019, The tremendous diversity of Labiobaetis Novikova & Kluge in Indonesia (Ephemeroptera, Baetidae), ZooKeys 895, pp. 1-117 : 1

publication ID

https://dx.doi.org/10.3897/zookeys.895.38576

publication LSID

lsid:zoobank.org:pub:11350FE9-21E6-4D7A-B1F9-16CE4639F406

persistent identifier

https://treatment.plazi.org/id/A6C2AB9F-9EBC-434A-AD50-84D31BF4F74B

taxon LSID

lsid:zoobank.org:act:A6C2AB9F-9EBC-434A-AD50-84D31BF4F74B

treatment provided by

ZooKeys by Pensoft

scientific name

Labiobaetis sumbensis
status

sp. nov.

3. Labiobaetis sumbensis sp. nov. Figures 6 View Figure 6 , 7 View Figure 7 , 47c View Figure 47 , 52b View Figure 52 , 54a View Figure 54

Diagnosis.

Larva. Following combination of characters: A) dorsal surface of labrum with submarginal arc of 1 + 5 long, simple setae; B) labial palp segment II with a large, lobed distomedial protuberance, segment III oblong; C) fore femur rather broad, length ca. 3 × maximum width, dorsal margin with a row of ca. ten curved, spine-like setae; D) fore claw with 12-14 denticles; E) paraproct distally not expanded, with 19-24 stout marginal spines.

Description.

Larva ( Figs 6 View Figure 6 , 7 View Figure 7 , 47c View Figure 47 , 52b View Figure 52 ). Body length 4.4 mm; antenna approximately twice as long as head length.

Colouration. Head, thorax, and abdomen dorsally brown, head and thorax with bright median, dorsal suture, thorax and abdomen with pattern as in Fig. 47c View Figure 47 , forewing pads with brown striation. Head, thorax, and abdomen ventrally brown, femur with dorsal and ventral brown streaks, proximally connected, distally brown and with a distomedial brown spot ( Fig. 52b View Figure 52 ), tibia and tarsus light brown. Caudal filaments light brown, with a dark brown band at ca. 2/3 of cerci.

Antenna with scape and pedicel subcylindrical, with well-developed distolateral process at scape; flagellum with lanceolate spines and fine, simple setae on apex of each segment.

Labrum ( Fig. 6a View Figure 6 ). Rectangular, length 0.7 × maximum width. Distal margin with medial emargination and a small process. Dorsally with long, fine, simple setae scattered over surface; submarginal arc of setae composed of 1 + 5 long, simple setae, the first two setae after the central seta are closely together. Ventrally with marginal row of setae composed of lateral and anterolateral long, feathered setae and medial long, bifid, pectinate setae; ventral surface with six short, spine-like setae near lateral and anterolateral margin.

Right mandible ( Fig. 6b, c View Figure 6 ). Incisors fused. Outer and inner sets of denticles with 4 + 3 denticles and one minute 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. 6d, e View Figure 6 ). Incisors fused. Outer and inner sets of denticles with 3 + 3 denticles. Prostheca robust, apically with small denticles and comb-shaped 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 absent.

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

Hypopharynx ( Fig. 6f View Figure 6 ). Lingua approx. as long as superlingua. Lingua longer than broad; medial tuft of stout setae well developed, short; distal half not expanded. Superlingua rounded; lateral margin rounded; fine, long, simple setae along distal margin.

Maxilla ( Fig. 6g View Figure 6 ). Galea-lacinia with three 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 1.3 × as long as length of galea-lacinia; two segmented; palp segment II 1.2 × length of segment I; setae on maxillary palp fine, simple, scattered over surface of segments I and II; apex of last segment rounded, with slight excavation at inner distolateral margin.

Labium ( Fig. 6h View Figure 6 ). Glossa basally broad, narrowing toward apex; shorter than paraglossa; inner margin with eight spine-like setae, distalmost seta much longer than other setae; apex with two long and one medium, robust, pectinate setae; outer margin with six spine-like setae; ventral surface with short, fine, simple setae. Paraglossa sub-rectangular, curved inward; apex rounded; with three rows of long, robust, distally pectinate setae in apical area and two medium, simple setae in anteromedial area; dorsally with a row of five long, spine-like setae near inner margin. Labial palp with segment I approx. as long as length of segments II and III combined. Segment I ventrally with short, fine, simple setae. Segment II with large, lobed distomedial protuberance; distomedial protuberance 0.7 × width of base of segment III; inner and outer margin with short, fine, simple setae; dorsally with a row of five long, spine-like, simple setae near outer margin. Segment III oblong; apex rounded; length 1.1 × width; ventrally covered with short and medium spine-like, simple setae and short, fine, simple setae.

Hind wing pads absent.

Foreleg ( Fig. 7a, b View Figure 7 ). Ratio of foreleg segments 1.2:1.0:0.6:0.2. Femur. Length ca. 3 × maximum width. Dorsal margin with a row of ca. ten curved, spine-like setae; length of setae 0.16 × maximum width of femur. Apex rounded; with one pair of curved, spine-like setae and some short, stout setae. Many stout, lanceolate setae scattered along the ventral margin; femoral patch reduced to a few setae. Tibia. Dorsal margin with a row of short, stout setae and fine, simple setae; on apex one longer, spine-like, apically rounded seta. Ventral margin with a row of curved, spine-like setae, on apex several spine-like, partly bipectinate setae and a tuft of fine, simple setae. Anterior surface scattered with stout, lanceolate setae. Patellotibial suture present on basal 1/2. Tarsus. Dorsal margin with a row of short, stout setae and fine, simple setae. Ventral margin with a row of curved, spine-like setae. Tarsal claw with one row of 12-14 denticles; distally pointed; with five stripes; subapical setae absent.

Tergum ( Fig. 7c View Figure 7 ). Surface with irregular rows of U-shaped scale bases and micropores. Posterior margin of tergum IV with triangular spines, approx. as long as wide.

Gills ( Fig. 7d View Figure 7 ). Present on segments I–VII. Margin with small denticles intercalating fine simple setae. Tracheae extending from main trunk to inner and outer margins. Gill I ca. 3/4 length of segment II. Gill IV as long as length of segments V and VI combined. Gill VII as long as length of segments VIII and 1/2 IX combined.

Paraproct ( Fig. 7e View Figure 7 ). Distally not expanded, with 19-24 stout marginal spines. Surface scattered with U-shaped scale bases, fine, simple setae and micropores. Cercotractor with numerous small marginal spines.

Etymology.

Refers to the island Sumba, where the specimens were collected.

Distribution.

Indonesia: Sumba.

Biological aspects.

The specimens were collected in streams at an altitude of 400 m and 470 m and in waterholes at an altitude of 150 m.

Type-material.

Holotype. Larva (on slide, GBIFCH 00657749), Indonesia, Sumba, Waikelo, stream, 400 m, 27.IX.2011, 09°35.75'S, 119°20.42'E, M. Balke leg. (SUA04). Temporary deposited in MZL before definitely housed in MZB. Paratypes. 1 larva (on slide, GBIFCH 00592193, deposited in MZL), same data as holotype; 3 larvae (2 on slides, GBIFCH 00592191, GBIFCH 00592192, deposited in MZL; 1 in alcohol, GBIFCH 00515346, deposited in ZSM), Indonesia, Sumba, forest stream, 470 m, 27.IX.2011, 09°38.62'S, 119°40.93'E, M. Balke leg. (SUA07); 1 larva (on slide, GBIFCH 00235825, deposited in MZL), Indonesia, Sumba, Waitabula env., waterholes nr. limestone well, 150 m, 26.IX.2011, 09°26.06'S, 119°18.53'E, M. Balke leg. (SUA01).

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Ephemeroptera

Family

Baetidae

Genus

Labiobaetis