Sellanucheza ancorata sp. nov.
Figs 11, 12, 13
Type material.
• Holotype ♂ (SM-08), Laos, Khammouane Province, 2.5 km west-northwest of Ban Tathot, Tham Kamouk, large halled limestone cave, 200 m a. s. l., 17°37'53.5"N, 105°07'25.7"E, 06. 08. 2016, leg. P. Jäger.
Diagnosis.
The new species is distinguished from all congeners by the unique, anchor-shaped (trifid) solenophore tip. Somatically, it differs from the two other Laotian new species above by its intermediate size (ca 21 mm) and uniform brown yellowish coloration (vs small and pallid in S. laotica sp. nov.; large and dark in S. longispina sp. nov., lacking the specific sternal modifications found in either species). The gonopods (Figs 13, 14) are highly characteristic: process pb short, stout and laminiform (vs large, laminiform and bifid in S. longispina sp. nov., long and subunciform in S. jaegeri, or small and acute in S. tenebra); process pa distinctively long, slender and spiniform with an acute tip directed ventromesad (vs shorter, spiniform and suberect in S. laotica sp. nov., or large and acute in S. grandis) and the solenophore tip is split into three distinct prongs (central straight, lateral recurved), a characteristic unique to this species.
Description.
Length 20.8 mm (♂), width of midbody pro- and metazona 1.6 and 2.1 mm (♂), respectively.
Coloration of alcohol material after nine years of preservation uniform brown yellowish (Fig. 12 A – G); legs and antennae a little paler, tip of antenna dark brown.
Clypeolabral region and vertex sparsely setose, epicranial suture distinct. Antennae moderately long, reaching body ring 3 (♂) when stretched dorsally. In width, head <ring 3 <4 <collum <ring 2 <5 <6 <7–17 (♂); thereafter body gently and gradually tapering.
Collum with three transverse rows of setae: 4 + 4 anterior, 2 + 2 intermediate and 3 + 3 posterior; lateral margin with a small incision in posterior half; posterior corner of paraterga very narrowly rounded, slightly declined ventrad, extending past tergal margin (Fig. 12 A, B).
Tegument smooth and shining, prozona very finely shagreened, metaterga smooth and faintly rugulose (Fig. 12 A – G); surface below paraterga finely microgranulate (Fig. 12 B, D, E). Postcollum metaterga with two transverse rows of setae: 2 + 2 in anterior (pre-sulcus) and 3 + 3 in posterior (post-sulcus) row. Tergal setae long, strong, slender, ca 1 / 3 metatergal length. Axial line faint, barely traceable on metaterga.
Paraterga well developed (Fig. 12 A, C, F), set high (at upper 1 / 3 of body), subhorizontal, lying below dorsum; anterior edge broadly rounded and narrowly bordered, fused to callus; lateral edge without incisions; posterior corner very narrowly rounded, not extending past tergal margin except for rings 17–19 where it becomes increasingly pointed (Fig. 12 E, F); posterior edge nearly straight. Paraterga 2 broad, slightly upturned posteriorly, anterior edge rounded, lateral edge with a small incision in anterior half; posterior edge concave (Fig. 12 B). Calluses on paraterga narrow, each demarcated by a sulcus only dorsally. Ozopores evident, lateral, each lying in an ovoid groove at ca 1 / 4 metatergal length in front of posterior corner (Fig. 12 B, D, E).
Transverse sulci distinct (Fig. 12 A, C, F), complete on metaterga 6–18, narrow, line-shaped, shallow, not reaching the bases of paraterga, smooth at bottom, incomplete and nearly wanting on ring 5. Stricture between pro- and metazona narrow, beaded at bottom down to base of paraterga (Fig. 12 A, C). Pleurosternal carinae complete crests on anterior rings, thereafter gradually reduced posteriad until ring 16 (♂) (Fig. 12 B, D, E).
Epiproct (Fig. 12 E – G) conical, rounded dorsoventrally, with two small and evident apical papillae; tip subtruncate; pre-apical papillae small, lying close to tip (Fig. 12 F, G). Hypoproct roundly subtriangular (Fig. 12 G), setiferous knobs at posterior edge well-separated and evident.
Sterna sparsely setose, cross-impressions shallow, without modifications; a single, linguiform, densely setose, sternal lobe between ♂ coxae 4 (Fig. 12 H, I). Legs moderately long and slender, midbody legs ca 1.1–1.3 × as long as body height; ♂ prefemora without modifications; tarsal brushes present until ♂ ring 16.
Gonopods (Figs 13, 14) simple. Coxite long, stout, subcylindrical, relatively straight, but slightly curved dorsally, with a dense group of setae distodorsally (Figs 13 A, 13 B, 13 C, 14 A, 14 B). Prefemorite (pfe) densely setose, as usual, relatively short, ca 1 / 3 length of acropodite (Figs 13 A, 13 B, 13 C, 14 A, 14 B). Femorite (fe) stout, relatively long, suberect, with a distinct. clearly visible lateral suture (Figs 13 A – D, 14 A, 14 B). Distal part of femorite supplied with two distinct processes: process pb (pb) short, stout, laminiform, elevated dorsally, with a rounded apical margin (Figs 13 A – C, 13 G, 13 F, 14 A, 14 B); process pa distinctively long, slender, spiniform, clearly curved, with an acute tip directed ventromesad (Figs 13 A, 13 B, 13 D, 13 G, 14 A). Solenophore (sph) long, slender, directed anteriad and slightly curved; tip highly characteristic, trifid; central prong straight to slightly curved, while two lateral processes recurved and pointing basally (Figs 13 A – G, 14 A, 14 B). Solenomere long, slender, almost entirely sheathed by solenophore, forming a distinct anchor shape (Figs 13 G, 14 A, 14 B).
Remarks.
It seems noteworthy that the natural structure of the gonopod is clearly shown in Fig. 14, 13 G. The structure depicted in most other views of Fig. 13 exhibits a distortion caused by the drying of the specimen during preparation. This process caused the solenomere (sl) to dislodge from the solenophore sheath and project posteriorly, an artifact that does not reflect the true morphology of the species. Geographically, Sellanucheza ancorata sp. nov. is currently known only from the type locality in Khammouane Province. This is a large-halled limestone cave (Fig. 15 D, E) which is not visited by tourists, although it is occasionally used by villagers as a shortcut between villages. The end of the cave features a ceiling breakdown with massive litter accumulation from the forest above (Fig. 15 C). In the rainy season, a river flows through the cave, and bats are present. The species appears to be narrowly endemic to its limestone karst system of the area, a pattern characteristic of many members of this genus in the Indochinese Peninsula.
Etymology.
To emphasize the characteristic anchor-shaped (trifid) tip of the solenophore; adjective.
Publication Date: 2026-06-23