Arcobaetis sumatrensis, Kaltenbach & Kluge & Gattolliat, 2023
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publication ID |
https://dx.doi.org/10.3897/zookeys.1168.104844 |
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publication LSID |
lsid:zoobank.org:pub:28A21391-A433-4E80-8845-E5C0996EFAF0 |
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persistent identifier |
https://treatment.plazi.org/id/D595E315-4847-481C-9297-1792ADF392D4 |
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taxon LSID |
lsid:zoobank.org:act:D595E315-4847-481C-9297-1792ADF392D4 |
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treatment provided by |
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scientific name |
Arcobaetis sumatrensis |
| status |
sp. nov. |
Arcobaetis sumatrensis sp. nov.
Figs 6 View Figure 6 , 7 View Figure 7 , 8 View Figure 8 , 9 View Figure 9 , 19 View Figure 19
Type material.
Holotype. Indonesia • female larva (premature); Sumatra Barat, Harau Canyon, stream near Ikbal’s cottage, UN11; 00°06'26"S, 100°40'22"E; 520 m; 23.vi.2012; leg. M. Balke; on slide; GBIFCH00592617; MZB. Paratypes. 1 larva; same data as holotype; on slide; GBIFCH00975679; MZL • 1 larva; Sumatra Barat, Bukit Barisan, above Padang, creek, UN3; 00°56'44"S, 100°32'44"E; 1047 m; 8.xi.2011; leg. M. Balke; on slide; GBIFCH00975704; MZL.
Diagnosis.
Larva (Table 1 View Table 1 ). The following combination of characters distinguish A. sumatrensis sp. nov. from other species of Arcobaetis gen. nov.: A) distal margins of segments in middle part of flagellum without enlarged spines; B) labial palp segment III sub-rectangular, at base smaller than distal margin of segment II (Fig. 7h View Figure 7 ); C) hind protoptera absent; D) claw with single row of denticles, ca. six distalmost denticles larger, other denticles minute (Fig. 8b View Figure 8 ); E) tergalii present on abdominal segments II-VII (Fig. 8c-h; F View Figure 8 ) posterior margin of tergum IV with triangular spines, wider than long (Fig. 7i View Figure 7 ).
Description.
Larva (Figs 6 View Figure 6 - 9 View Figure 9 ). Body length ca. 4.6 mm.
Cuticular colouration (Fig. 6a-c View Figure 6 ). Head, thorax, and abdomen dorsally brown, ventrally ochre. Legs ochre, joining of femur and tibia dark brown; middle part of tibia pale brown. Caudalii pale brown.
Hypodermal colouration. Abdomen dorsally with narrow reddish transverse stripes on intersegmental membranes (Fig. 6a View Figure 6 ).
Antenna. Flagellum in middle part without enlarged spines at distal margin of segments.
Labrum (Fig. 7a View Figure 7 ). Length 0.7 × maximum width. Dorsally with sub-median seta and sub-marginal arc of two simple setae.
Right mandible (Fig. 7b, c View Figure 7 ). Incisor with five denticles; kinetodontium with three denticles.
Left mandible (Fig. 7d, e View Figure 7 ). Incisor with four denticles; kinetodontium with three denticles.
Hypopharynx and superlinguae (Fig. 7f View Figure 7 ). Lingua as long as superlinguae, longer than broad. Superlinguae distally straight; lateral margins rounded; fine, long, simple setae along distal margin.
Maxilla (Fig. 7g View Figure 7 ). Galea-lacinia ventrally with two simple setae just proximad of canines. Medially with one pectinate, spine-like seta and ca. five short to long, simple setae. Maxillary palp approx. 1.5 × as long as galea-lacinia; palp segment II approx. 1.2 × as long as segment I; setae on maxillary palp fine, simple, scattered over surface of segments I and II.
Labium (Fig. 7h-j View Figure 7 ). Inner margin of glossa with ca. ten spine-like setae; apex with three long and one medium robust setae; outer margin with ca. nine spine-like setae; paraglossa ventrally with ca. two medium, simple setae in anteromedial area; dorsally with arc of ca. ten long, spine-like setae in distal area. Labial palp with segment I 0.8 × length of segments II and III combined. Segment II dorsally with row of ca. four spine-like setae. Segment III sub-rectangular; at base narrower than distal margin of segment II; ventral surface with short, spine-like, simple setae and short, fine, simple setae.
Hind protoptera absent.
Legs (Figs 8a, b View Figure 8 , 9a-c View Figure 9 ). Long and slender, middle, and hind legs slenderer than fore leg. Ratio of leg segments: fore leg 1.4:1.0:0.8:0.2, middle legs 1.3:1.0:0.6:0.2 and hind legs 1.2:1.0:0.6:0.1. Femur. Length of fore femur ca. 4.4 × maximum width, outer and inner margins almost parallel; length of middle and hind femora> 5 × maximum width, outer margins slightly concave. Outer margin with row of ca. seven short, curved, spine-like setae, on fore leg larger than on middle and hind legs. On ventral side of fore leg with short, spine-like, pectinate, pointed setae; nearly absent on middle and hind legs. Tibia. Short, stout, pointed, pectinate setae irregularly near inner margin. Inner margin with row of short, curved, spine-like, pectinate setae, on apex two longer, curved, spine-like, pectinate setae. Outer margin with one apical, spine-like seta; on fore leg without other spine-like setae, on middle and hind legs with few medium, spine-like setae. Patella-tibial suture on proximal ¹/4 of tibia on all legs. Tarsus. Inner margin with row of short, curved, pectinate, spine-like setae; outer margin without spine-like setae. Claw with single row of denticles, ca. six distalmost denticles larger and directed distad, other denticles minute.
Abdominal terga (Fig. 8i, j View Figure 8 ). Posterior margin of terga: I smooth, without spines; II-IV with short triangular spines, wider than long; V with triangular spines approx. as wide as long; VI-IX with triangular spines longer than wide, sharply pointed; row of spines on tergum IX interrupted by smaller spines in middle part behind bases of submedian setae (similar to Fig. 15j View Figure 15 ).
Abdominal sterna. Posterior margins of sterna: I-V smooth, without spines; VI-IX with triangular spines.
Tergalii (Figs 8c-h View Figure 8 , 9d View Figure 9 ). Present on abdominal segments II-VII. Tracheation partially extending toward inner and outer margins. Margins with minute denticles intercalating short, simple setae.
Paraproct (Fig. 8k View Figure 8 ). Posterior margin with ca. 13 stout spines. Surface scattered with scale bases and micropores.
Caudalii (Fig. 9f View Figure 9 ). Cerci and paracercus with small, rather wide, triangular, pointed spines on posterior margin of each segment; on outer side of cerci two somewhat longer spines on each 2nd segment, no such longer spines on paracercus.
Etymology.
The specific epithet refers to the type locality in Sumatra (Indonesia).
Distribution.
Indonesia: Sumatra (Fig. 12b View Figure 12 ).
Biological aspects.
The species was found at altitudes of 520 m and 1050 m.
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.