Penares orbis, Sim-Smith & Kelly, 2019

Sim-Smith, Carina & Kelly, Michelle, 2019, Review of the sponge genus Penares (Demospongiae, Tetractinellida, Astrophorina) in the New Zealand EEZ, with descriptions of new species, Zootaxa 4638 (1), pp. 1-56 : 38-40

publication ID	https://doi.org/ 10.11646/zootaxa.4638.1.1
publication LSID	lsid:zoobank.org:pub:E5A26EB4-1F98-4310-A8D7-A0F933E75D95
persistent identifier	https://treatment.plazi.org/id/03CB87E6-FFB9-F966-FF7B-FA10FBA5FA05
treatment provided by	Plazi
scientific name	Penares orbis
status	sp. nov.

Treatment

Penares orbis sp. nov.

( Fig. 30–33 View FIGURE 30 View FIGURE 31 View FIGURE 32 View FIGURE 33 ; Table 10 View TABLE 10 )

Material examined. Holotype — NIWA 81643 View Materials , NIWA Stn TAN1206/40, Kermadec Ridge, 36.446° S, 177.837° E, 1100–1170 m, 18 Apr 2012 GoogleMaps . Paratypes — NIWA 81648 View Materials , NIWA Stn TAN1206/39, Kermadec Ridge, 36.452° S, 177.846° E, 1030–1255 m, 18 Apr 2012 GoogleMaps ; NIWA 62492 View Materials , NIWA Stn TAN1104/18, Hikurangi Plateau, 36.450° S, 177.840° W, 836–840 m, 4 Mar 2011 GoogleMaps . Other material. Three Kings Ridge: NIWA 43892 View Materials , NZOI Stn Z9025, 31.980° S, 174.265° E, 677–1680 m, date unknown GoogleMaps ; NIWA 43894 View Materials , NZOI Stn U 594, 30.335° S, 172.993° E ( International Waters ), 406 m, 7 Feb 1988 GoogleMaps .

Bay of Plenty: NIWA 52486 View Materials , NIWA Stn TAN0413/177, 37.312° S, 177.066° E, 550–725 m, 16 Nov 2004 GoogleMaps .

Kermadec Ridge: NIWA 81645 View Materials , NIWA Stn TAN1206/39, 36.452° S, 177.846° E, 1030–1255 m, 18 Apr 2012 GoogleMaps ; NIWA 81653 View Materials , NIWA Stn TAN1206/95, 36.451 °S, 177.840 °E, 840–872 m, 24 Apr 2012 GoogleMaps .

Type locality. Southern Kermadec Ridge , New Zealand .

Distribution. Found in northeastern New Zealand; 406–1680 m ( Figure 33 View FIGURE 33 ).

Description. Morphology is a small, amorphous sponge comprised of several lobes ( Figure 30A View FIGURE 30 ), holotype is growing around dead coral branches. The holotype is 40 mm long × 30 mm wide × 15 mm high. Surface is crum- pled, uneven with irregular, shallow depressions all over the sponge, scratchy to the touch. A few large oscules, around 3 mm diameter, are present at the apex of the lobes ( Figure 30C View FIGURE 30 ). Very small, uniporal pores, not visible to the naked eye (130–150 µm in diameter), are densely scattered over the surface of the sponge ( Figure 30D View FIGURE 30 ). Texture is very hard, incompressible. Colour in ethanol is cream, interior is beige.

Skeleton. Cortical skeleton is 300–500 µm thick and consists of a densely packed layer of tangential microxeas ( Figure 31A View FIGURE 31 ). Choanosomal skeleton has a layer of abundant dichotriaenes present, cladomes positioned extend beyond the surface of the sponge ( Figure 30B View FIGURE 30 ) as well as being positioned directly below the cortex ( Figure 31C View FIGURE 31 ). Spherasters are scattered in a band <100 µm thick just below the cortex/choanosome boundary ( Figure 31B View FIGURE 31 ) but are rarely present in the rest of the choanosome. Megascleres are a mixture of oxeas, tylostyles and tylostrongyles, which are present in the inner choanosome. Microxeas are very densely packed throughout the choanosome ( Figure 31D View FIGURE 31 ). Small, round, spherules are scattered throughout the choanosome.

Spicules ( Figure 32 View FIGURE 32 ; Table 10 View TABLE 10 ). Megascleres —tylostyles ( Figure 32A View FIGURE 32 ) are moderately long, slightly curved and of greatly varying width from thin to quite stout; 2376 (1553–3293) × 63 (21–123) µm (n = 56). Oxeas ( Figure 32C View FIGURE 32 ) are a similar size to tylostyles; 2378 (1117–3533) × 51 (16–143) µm (n = 66). Tylostrongyles ( Figure 32B View FIGURE 32 ) are straight and stout; 1997 (1175–2688) × 72 (38–110) µm (n = 21). Dichotriaenes ( Figure 32D View FIGURE 32 ) have a short rhabdome that often has a tylote or bluntly rounded tip ( Figure 32E View FIGURE 32 ). Clads are broad, flattened and leaf-like. Protoclads are much shorter than deuteroclads ( Figure 32F View FIGURE 32 ). One or more clads may be trifurcate ( Figure 32G View FIGURE 32 ). The cladome is approximately twice as wide as the rhabdome length; 645 (390–984) µm long × 1046 (571–1660) µm wide (n = 75).

Microscleres —microxeas ( Figure 32H View FIGURE 32 ) are variable in size with sharply pointed or slightly rounded tips. Some are faintly centrotylote; 97 (33–207) × 6 (3–9) µm (n = 128). Spherules ( Figure 32I View FIGURE 32 ) are small and completely smooth; 11 (5–23) µm in diameter (n = 60). Spherasters ( Figure 32J View FIGURE 32 ) are very small with numerous smooth, conical rays; 10 (7–13) µm in diameter (n = 65).

Etymology. Named after the smooth spherules present in this species ( orbis , globe; Latin).

Remarks. The combined presence of spherules and spherasters differentiates P. orbis sp. nov. from all other Penares species. The presence of either spherules or spherasters in species of Penares is relatively unusual, but not unprecedented. Three species ( P. dendyi ( Hentschel, 1912) from Indonesia, P. metastrosa from Japan ( Lebwohl, 1914), and P. sphaera ( Lendenfeld, 1907) from South Africa) possess spherules but no spherasters, while P. micraster Lévi, 1993 from New Caledonia possesses spherasters but no spherules.