Branchiobaetis minangkabau, Kaltenbach & Kluge & Gattolliat, 2022
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publication ID |
https://dx.doi.org/10.3897/zookeys.1135.93800 |
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publication LSID |
lsid:zoobank.org:pub:0915A6D8-A8C5-4C7A-9560-1D6EF9E14B0F |
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persistent identifier |
https://treatment.plazi.org/id/B434954C-6136-4B65-9810-804B6B5581C9 |
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taxon LSID |
lsid:zoobank.org:act:B434954C-6136-4B65-9810-804B6B5581C9 |
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treatment provided by |
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scientific name |
Branchiobaetis minangkabau |
| status |
sp. nov. |
6. Branchiobaetis minangkabau sp. nov.
Figs 20 View Figure 20 , 21 View Figure 21 , 25a View Figure 25 , 26d View Figure 26 , 28b View Figure 28
Type material.
Holotype. Indonesia • Sumatra, volcano Talamau, River Pularian; 00°02'15"S, 99°59'24"E; 960 m; 01.IV.2014; leg. M. Gueuning; larva on slide; GBIFCH00592524; MZL. Paratypes. Same data as holotype; larva on slide; GBIFCH00422480; MZL; 18 larvae in alcohol; GBIFCH00406299, GBIFCH00406308, GBIFCH00406398, GBIFCH00406407, GBIFCH00422240, GBIFCH00422245, GBIFCH00422247, GBIFCH00422257, GBIFCH00422262, GBIFCH00422269, GBIFCH00422481, GBIFCH00422527, GBIFCH00422534, GBIFCH00423110, GBIFCH00980904; MZL. Indonesia • West Sumatra, Sawahlunto, Talawi Hilir, Dusun Talimato, UB Farm; 0°35'52"S, 100°43'02"E; 305 m; 25.X.2013; leg. M. Balke; larva on slide; GBIFCH00763628; MZB (temporarily housed in MZL); larva on slide; GBIFCH00592445; MZL; 2 larvae in alcohol; GBIFCH00975608, GBIFCH00980900; MZL.
Differential diagnosis.
Larva. Following combination of characters distinguish B. minangkabau sp. nov. from other species of Branchiobaetis gen. nov.: A) labial palp segment II with small protuberance; segment III slightly pentagonal, apically slightly concave, with projecting point (Fig. 20h View Figure 20 ); B) dorsal margin of femur with row of long, spine-like setae, denser in basal area (Fig. 21a View Figure 21 ); C) posterior margin of tergites: I smooth, without spines; II-IV with rounded spines, wider than long, partly fused at base; V-IX with triangular spines, narrower and longer towards last segment (Fig. 21d View Figure 21 ); posterior margin of sternites: I-VI smooth, without spines; VII and VIII with small, spaced, triangular spines; IX with small, triangular spines; D) paraproct without short, stout, apically rounded setae along posterior margin (Fig. 21f View Figure 21 ).
Description.
Larva (Figs 20 View Figure 20 , 21 View Figure 21 , 25a View Figure 25 , 26d View Figure 26 ). Body length 6.5-8.5 mm. Cerci: ca. 2/3 of body length. Paracercus: ca. 1/2 cerci length. Antenna: ca. 2.5 × as long as head length.
Colouration (Fig. 25a View Figure 25 ). Head, thorax and abdomen dorsally brown, abdominal segments I and X lighter, abdomen laterally on segments II-IX whitish; head, thorax and abdomen ventrally light brown. Legs with dark brown coxae, femur light brown, apically and dorsally along margin dark brown, with large, medial, dark brown spot; tibia light brown; tarsus basally light brown, dark brown in distal half. Caudalii light brown, primary swimming setae dark brown.
Precursors of turbinate eyes (Fig. 25e View Figure 25 ) in male last instar larvae representing a pair of egg-shaped maculae; in the middle of this macula, a smaller, round, elevated area with well-expressed facets, ca. eight facets in diameter; peripheral area of the macula with indistinct facets.
Antenna (Fig. 21g View Figure 21 ). Scape distally and outside distolaterally with short, stout, apically rounded setae.
Labrum (Fig. 20a View Figure 20 ). Length 0.6 × maximum width. Submarginal arc of setae composed of 11-13 long, simple setae.
Right mandible (Fig. 20b, c View Figure 20 ). Incisor and kinetodontium distally cleft. Incisor blade-like with three denticles; kinetodontium with four denticles. Minute setae outside laterally on first denticle (present on fresh mandibles only). Margin between prostheca and mola straight, with minute denticles.
Left mandible (Fig. 20d, e View Figure 20 ). Incisor blade-like with three denticles; kinetodontium with three denticles. Minute setae outside laterally on first denticle (present on fresh mandibles only). Margin between prostheca and mola straight, with minute denticles towards subtriangular process.
Both mandibles with lateral margins almost straight.
Hypopharynx and superlinguae (Fig. 20f View Figure 20 ). Lingua as long as superlinguae. Lingua longer than broad; medial tuft of stout setae well developed, long. Superlinguae distally rounded; lateral margins rounded; fine, long, simple setae along distal margin.
Maxilla (Fig. 20g View Figure 20 ). Galea-lacinia ventrally with one simple, apical seta under canines. Medially with one pectinate, spine-like seta and three or four medium, simple setae. Maxillary palp as long as galea-lacinia; palp segment II 1.1 × as long as segment I; setae on maxillary palp fine, simple, scattered over surface of segments I and II.
Labium (Fig. 20h View Figure 20 ). Inner margin of glossa with approx. eight spine-like setae, increasing in length distally; apex with two long and one medium, robust setae; outer margin with two or three spine-like setae; Paraglossa with one simple seta in posterolateral area; dorsally with two 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 small, distomedial protuberance; distomedial protuberance 0.3 × width of base of segment III; ventral surface with short, fine, simple setae; dorsally with 6-9 spine-like setae near outer margin, not always in a row. Segment III slightly pentagonal, apically slightly concave, with projecting point; length approx. maximum width; ventrally covered with short, spine-like, simple setae and short, fine, simple setae.
Foreleg (Fig. 21a-c View Figure 21 ). Ratio of foreleg segments 1.4:1.0:0.6:0.2. Femur. Length ca. 3 × maximum width. Dorsal margin with row of 15-20 long, curved, spine-like setae, basally denser. Many short, stout, apically rounded setae scattered along ventral margin. Apex rounded, with pair of long, spine-like setae and some short, stout setae. Tibia. Dorsal margin with row of short, stout setae. On surface few such setae along patella-tibial suture. Ventral margin with row of short, curved, spine-like setae, on apex a tuft of fine, simple setae. Tarsus. Dorsal margin with row of short, stout setae. Claw with one row of eight or nine denticles.
Terga (Fig. 21d View Figure 21 ). Surface with irregular rows of U-shaped scale bases. Posterior margin of tergites: I smooth, without spines; II-IV with rounded spines, wider than long, partly fused at base; V-IX with triangular spines, narrower and longer towards last segment. Posterior margin of sternites: I-VI smooth, without spines; VII-VIII with small, spaced, triangular spines; IX with small triangular spines.
Tergalii (Figs 21e View Figure 21 , 26d View Figure 26 ). Tracheae not reaching inner and outer margins; indistinct broad, light brown band along main trunk of tracheae on anal side. Tergalius I as long as 2/3 of segment II, tergalius IV as long as length of segments V and 2/3 VI combined, tergalius VII as long as length of segments VIII and 1/3 IX combined.
Paraproct (Fig. 21f View Figure 21 ). Posterior margin with 14-24 stout spines. Without short, stout setae near posterior margin. Surface scattered with scale bases, micropores and fine, simple setae.
Etymology.
Dedicated to the indigenous Minangkabau people, who live in the area of Sumatra where the specimens were collected.
Distribution.
Indonesia: Sumatra (Fig. 28b View Figure 28 ).
Biological aspects.
The specimens were collected on altitudes of 300 m and 960 m, most of them in a stream with the following physical conditions: slope 25%, width of stream 3-20 m, depth ca. 1.5 m, velocity slow in pool and 0.8 m/s in cascade, pH 8, stream bed dominated by bedrock and stones with patches of sand.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.