Corvospongilla lampaoensis Ruengsawang & Sangpradub & Cubeddu & Pronzato & Manconi 2024, sp. nov.
Creators: name: Ruengsawang, Nisit
name: Sangpradub, Narumon
name: Cubeddu, Tiziana
name: Pronzato, Roberto
name: Manconi, Renata
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Porifera
Demospongiae
Spongillida
Spongillidae
Corvospongilla
Corvospongilla lampaoensis

description: Corvospongilla lampaoensis Ruengsawang & Manconi sp. nov.
urn:lsid:zoobank.org:act: 0682FDF8-7972-43B8-B42D-F1AE3989CEF0
Figures 1–6
Materials. Holotype CNR-POR-FW 120, 14.vi.2018, leg. N. Ruengsawang, type locality near Thepsuda Bridge (16°42’42.1”N, 103°27’00.6”E) of Lam Pao Reservoir, Lower Mekong Basin, 163 m above sea level (asl), Nong Bua, Nong Kung Si District, Kalasin Province, Thailand. Paratype CNR-POR-FW 121-12, dry specimen, ibidem, 14.vi.2018, leg. N. Ruengsawang. Specimens, slides and SEM stubs are preserved in Collection Nisit Ruengsawang (CNR-POR-FW), Bangkok. For topotypes collected in November 2023 and January 2024 the registration CNR-POR-FW is in progress.
Comparative materials. Genus Corvospongilla, 15 species. C. becki Poirrier, 1978, USNM dry topotypes, RM & RP-FWPOR 919, 920, 921, Duck Lake, Louisiana, USA; C. burmanica (Kirkpatrick, 1908), BMNH 82.3.22.1–3, box 6, dry, type, RM & RP-FWPOR 420 schizotype, Myanmar; C. burmanica (?), BMNH 86.10.29.1, RM & RP-FWPOR 636, River Kuano, NE India; C. caunteri Annandale, 1911, BMNH 14.11.24.27 ex-ZEV 4776/ 7 paratype, RM & RP-FWPOR 637 schizotype, Lucknow, NE India; C. lapidosa (Annandale, 1908), BMNH 08.2.11. 1 paratype, RM & RP-FWPOR 638 schizotype, River Godavery Nasik, S-India; C. lemuriensis Manconi & Pronzato, 2019 MSNG 60893a holotype, RM & RP-FWPOR 807 schizoholotype, RM & RP-FWPOR 804 topotype, Farihy Amboromalandi Reservoir,NW Madagascar; C.loricata (Weltner, 1895), ZMB 2093 SE325-SE37– 41 type, RM & RP-FWPOR 511 schizotype, locality unknown, Africa; C. mesopotamica Manconi & Pronzato, 2004, MSNG 51766 holotype, RM & RP-FWPOR 574 schizotype, River Diyala, NE Iraq; C. moochalabrensis Manconi & Erpenbeck, 2021, WAM Z29235 holotype, RM & RP-FWPOR 853 schizotype, Moochalabra Dam, NW Australia; C. siamensis Ruengsawang and Manconi, 2012, MSNG 56533 holotype, Ban Huai Sai, Pong River, Mekong Basin, NE Thailand; C. thysi (Brien, 1968), MRAC 1311 type, RM & RP-FWPOR 472 schizotype, Lake Barombi-ma-Mbu, Cameroun, W-Africa; C. ultima Annandale (1910), BMNH 14.11.24.29 ex-ZEV 4906/7, RM & RP-FWPOR 639 fragment, SIndia; C. ultima var. spinosa, BMNH 14.11.24.30 ex-ZEV 5106/7, RM & RP-FWPOR 640, Satara District, SE-India; C. zambesiana (Kirkpatrick, 1906), BMNH 1906.2.28. 2, 13 IIIC, RM & RP-FWPOR 623 (exDTRG), River Zambezi, E Africa; Palaeocorvospongilla cretacea Pronzato, Manconi and Samant, 2021 PGDG / BGVN /1/18,2/18,3/18,4/18, Upper Cretaceous (Maastrichtian), Deccan, Central India.
Diagnosis. Megascleres exclusively spiny oxeas in skeletal network and gemmular cage. Gemmuloscleres spiny to tubercled strongyles and strongyloxeas. Gemmular theca sessile. Outer layer scantly developed and strongly armed by multilayered gemmuloscleres to quite developed and armed by few gemmuloscleres. Pneumatic layer thin, continuous with dense, minute rounded chambers and few gemmuloscleres, or as scantly chambered patches among dense multilayered gemmuloscleres, to not chambered pneuma as thin scattered laminae lining the upper portion of theca. Inner layer ranging, in the same theca, from well developed, smooth, compact, lining the basal part of theca to thin, scattered, small laminae irregularly arranged directly adhering to gemmuloscleres layer inner surface at theca’s middle-upper portion.
Description
Growth form encrusting, irregular (~4.5 x 8.5 cm in diameter, ~ 0.7 cm in thickness). Colour brown to light brown in dry condition (Figure 2) and green-brownish in vivo. Consistency hard, fragile in dry condition. Oscules inconspicuous in dry specimens. Surface densely to irregular and slightly hispidate (Figure 3). Ectosomal skeleton hispid with no special architecture supporting the dermal membrane. Choanosomal skeleton as loose isotropic to anisotropic reticulate network of rounded to polygonal meshes, paucispicular to multispicular fibres/tracts with scanty spongin, and ill-defined, irregular skeletal network towards the basal portion (Figure 3). Spongin scanty in skeletal network and well developed at the level of gemmular theca and basal spongin plate (Figures 3, 5, 6). Basal spongin plate armed by megasclere oxeas loosely arranged. Megascleres dominant acanthoxeas (137.6– 160.1 x 7.3–11.5 m, n = 50), slightly curved with abruptly pointed tips and variably dense microspines. Styles and malformations rarely present. Rare slender, spiny oxeas with larger spines probably belonging to larvae (Figures 3 E-F). Microscleres few, scattered in the skeletal meshwork, variably curved micropseudobirotules (14.7–30.4 x 0.9–1.5 µm, n = 50) with thin smooth shaft bearing smooth pseudorotules at tips (4–9 µm in diameter) with 4–6 long, smooth recurved hooks (Figures 3F, 4). Gemmular cage as scattered not abundant acanthoxeas megascleres (Figure 5F) with irregularly distributed small spines (87.5–153 x 6.5–10 µm, n = 11) diverging for outline and spines from skeletal megascleres, and long acanthostrongyles with tubercles (67–88.5 x 7.8–12.2 µm, n = 4). Gemmules hemispherical variably flattened at the lower portion to subspherical (400–800 µm in diameter); abundant, sessile in large to small dense groups, variably adhering to the basal spongin plate, and sometimes partly sharing the gemmular thecas/cages (Figures 3, 5, 6). Foramen rarely evident, rounded with simple collar and a short porous tube. Gemmular theca bilayered to trilayered with tangential gemmuloscleres variably embedded and oriented and with layers variably developed and spatially arranged (Figures 5, 6). Outer layer from strongly armed by gemmuloscleres multilayers to scantly armed by few gemmuloscleres (Figures 5, 6). Pneumatic layer of dense, minute rounded chambers ranging (also in the same theca) from thin and continuous to as small patches in-between gemmuloscleres, or scantly developed to almost absent (Figure 6). Inner layer ranging (also in the same theca) from scattered trabeculae to compact smooth laminae, to multilayered laminae with smooth surface lining the basal part of theca and partly as thin, small trabeculae directly adhering to gemmuloscleres at the middle-upper part of theca (Figure 6). Gemmuloscleres frequently curved (~158°) acanthostrongyles (blunt tips) and acanthostrongyloxeas (acute tips) with ornamentations as small tubercles/spines, irregularly scattered, grouped or singly, along the shaft and denser at tips (Figures 5, 6). Dominant acanthostrongyles (56–104 x 8.5–12 µm, n = 50), less abundant acanthostrongyloxeas (80.5–113 x 7.5–11.5 µm, n = 50). Rare acanthoxeas (92–119 x 7–10 µm, n = 11) frequently curved (~162°). Malformations frequently present.
Etymology. The specific epithet lampaoensis is derived from the Lam Pao Reservoir, where Corvospongilla lampaoensis sp. nov. was discovered near the Thepsuda Bridge (type locality). Gender feminine.
Habitat and ecology. The population of Corvospongilla lampaoensis sp. nov. near the Thepsuda Bridge is dominant in lentic, brown, eutrophic shallow water, as large patches with encrusting habitus of variable thickness on hard manmade substrata e.g., fish traps and fish farming (Tilapia) cages structures i.e., plastic buoy, nylon rope, netting, rubble tire (Figure 2). Sponges were not found, until now, on the rare hard natural substrata along the coastline. The site is characterised by notable seasonal variations of water level as also suggested by the persistent presence of abundant gemmules during sampling replicas. Rafts for fish cage culture are seasonally managed and moved within the basin by fishermen according to the weather and water level variations (Figure 2). Aquatic insects, bryozoans, diatoms, and testate thecamoebae were found associated with sponges. Other sponges, with different growth forms, colour and spiculation, were also collected from the Thepsuda Bridge and from the other three sampling sites along the Lam Pao reservoir coastline (identification in progress).
Geographic distribution. Corvospongilla lampaoensis sp. nov. is only known, until now, from the type locality near Thepsuda Bridge (16°42’42.1”N, 103°27’00.6”E), Lam Pao Reservoir, Korat Plateau, Kalasin Province, NE Thailand (Figure 1). The species is endemic to the Mekong Basin, although more sampling effort is required to verify its geographic range also in other Indochina’s hydrographic basins.
description: Published as part of Ruengsawang, Nisit, Sangpradub, Narumon, Cubeddu, Tiziana, Pronzato, Roberto & Manconi, Renata, 2024, Biodiversity assessment of the Lower Mekong Basin: evolutionary novelties in gemmular morphotraits of Genus Corvospongilla (Porifera: Spongillida) with description of a new species from Khorat Plateau, and biogeographic notes, pp. 144-158 in Zootaxa 5529 (1) on pages 146-148, DOI: 10.11646/zootaxa.5529.1.7, http://zenodo.org/record/14022150