Placospongia giseleae, Mácola & Menegola, 2021

Mácola, Rosa & Menegola, Carla, 2021, A new species of Placospongia Gray, 1867 (Porifera, Demospongiae, Placospongiidae) and new record of P. ruetzleri van Soest, 2017 from Northeast, Brazil, Zootaxa 5072 (1), pp. 12-22 : 14-16

publication ID	https://doi.org/ 10.11646/zootaxa.5072.1.2
publication LSID	lsid:zoobank.org:pub:1106D210-A032-4196-9236-63FEDA36A74E
DOI	https://doi.org/10.5281/zenodo.5728935
persistent identifier	https://treatment.plazi.org/id/038CF27A-F44D-9B4C-FF74-FC0BF415F9B3
treatment provided by	Plazi
scientific name	Placospongia giseleae
status	sp. nov.

Treatment

Placospongia giseleae View in CoL sp. nov.

( Fig. 2 View FIGURE 2 ; Tab. 1 View TABLE 1 )

Material examined. Holotype. UFBA 4051 , Praia de Aratuba , Recife das Caramuanas, Vera Cruz, 13º08’S – 38º45’W, Bahia State, Brazil, 1–2 m deep, January 30, 2013, coll. Cavalcanti, F. & Neves, E. GoogleMaps

Paratype. UFBA 4050 , Paciência de Terra , Baía de Camamu, Maraú, 13°57’29.19”S – 38°54’47.95”W, Bahia State, Brazil, 18–20 m deep, October 23rd, 2012, coll. Menegola, C. & Guimarães, R. GoogleMaps

UFPE POR 1446 , Cabo de Santo Agostinho , Praia Enseada dos corais, 8º19’0.34’’S – 34º56’51.92’’W, Pernambuco State, Brazil, intertidal zone, November 29th, 2012, coll. Pinheiro, U. GoogleMaps

Diagnosis. Megascleres tylostyles I range from 650 to 1200 µm; Tylostyles II range from to 220 to 740 µm. Microscleres selenasters and acanthomicrorhabds.

Description. Encrusting sponge (Based on Holotype UFBA 4051 measurements: 72.31 150 mm length x 55.09 mm width and 4.05 mm thickness), covered by smooth and rigid cortical plates, separated by contractible grooves. Color in life light brown or dark brown ( Fig. 2A View FIGURE 2 ), retained after alcohol preservation ( Fig. 2B View FIGURE 2 ). Consistency is hard like a stone. Texture rugose, due to cortical plates. Oscules retracted after collection.

Skeleton. Cortex composed of densely packed selenasters, with acanthomicrorhabds in ectosomal surface, over the selenaster crust. Choanosome with tylostyle bundles outwardly disposed, supporting the cortex, emerging from a basal layer of selenasters. Selenasters in different developmental stages and acanthomicrorhabds widely scattered in choanosome ( Fig. 2C View FIGURE 2 ).

Spicules. Megascleres. Tylostyles in two size categories. Tylostyles I ( Fig. 2D View FIGURE 2 ), large, straight, with prominent tyles ( Fig. 2E View FIGURE 2 ) and blunt points ( Fig. 2F View FIGURE 2 ) (860–1033.5–1200 µm/7.5–11.9–15 µm). Tylostyles II ( Fig. 2G View FIGURE 2 ), small, straight, with hastate ends ( Fig. 2I View FIGURE 2 ) (220–402.9–740 µm / 5–6.9–10 µm).

Microscleres. Selenasters in distinct growth stages, bean-shaped, oval or spherical ( Fig. 2J View FIGURE 2 ) (35–59.5–71 µm / 22–45.1–52 µm) and young selenasters ( Fig. 2K View FIGURE 2 ) (20–26.9–33 µm/8–13.2–20 µm). Curved/sinuous or straight acanthomicrorhabds ( Fig. 2L View FIGURE 2 ), densely spined (6–9.1–11 µm/2–2.2–3 µm).

Ecology. Encrusting sponges, found on the underside of rocks, at 0–20 m depths.

Distribution. Southwest Atlantic, Brazil. Recorded from Northeast Brazil, Bahia State, Baía de Todos os Santos (Vera Cruz, Recife de Caramuanas, Aratuba beach) and south coast (Baía de Camamu, Maraú, Paciência da Terra). Pernambuco State, south coast (Cabo de Santo Agostinho, Praia Enseada dos Corais).

Etymology. The specific epithet is dedicated to Dr. Gisele Lôbo Hajdu, for her important contribution in teaching/guiding dozens of biology students from South America and Europe since the 90’s, in phylogeography, ecology, taxonomy and molecular biology of sponges.

Remarks. Placospongia giseleae sp. nov. is similar to the Pacific species P. santodomingoae , because of the similar spicule categories, showing tylostyles I with blunt ends and tylostyles II with hastate ends like and microscleres selenasters and acanthomicrorhabds are present. Nevertheless, the new species is unique by tylostyles I having twice the size (860–1033.5–1200/7.5–11.9–15µm) in comparison to the Pacific species (430–605.5–660/13– 15.5–20 µm). In addition, in P. giseleae sp. nov., tylostyles II are considerably longer (220–402.9–740 / 5–6.9–10 µm), when compared to tylostyles II of P. santodomingoae (240–290/5–8 µm).

Microrhabds are considerably smaller in Brazilian species (6–9.1–11/2–2.2–3 µm), than in P. santodomingoae (8–12.3–18/2.5–2.7–3.5 µm) ( Table 1 View TABLE 1 ). Selenasters measurements are also different, in the new species 35–59.5– 71/22–45.1–52 µm, being approximately the minimum size of the Pacific species (80–84.8–90/60–67.3–75µm).

Besides the morphological differences between these two species P. giseleae sp. nov. is found at coral reefs from tropical regions, while P. santodomingoae is exclusively found in anchialine pools from Indonesia. Therefore, the considerable distance between the Southwestern Atlantic and the Indo-Pacific Ocean, gives further evidence of specific distinctness, considering the limited dispersal ability of this genus ( Nichols & Barnes (2005).

The differences between the species recorded to the Caribbean Sea and the new species are mainly related to additional microscleres: (1) P. caribica presents spherasters, spirasters and oxyasters; (2) P. melobesioides shows spherules; (3) P. intermedia has spherasters and spirasters; (4). Furthermore, P. ruetzleri and the Brazilian species P. cristata has as additional microscleres, spirasters and spherasters, respectively. P. giseleae sp. nov. differs from all previous species by having only selenasters and acanthomicrorhabds as microscleres in spicule composition.