Agelas tubulata Lehnert

Parra-Velandia, Fernando J., Zea, Sven & Van Soest, Rob W. M., 2014, Reef sponges of the genus Agelas (Porifera: Demospongiae) from the Greater Caribbean, Zootaxa 3794 (3), pp. 301-343 : 321-322

Agelas tubulata Lehnert & van Soest, 1996

Fig. 8

Etymology from Latin, meaning little trumpet shape.

Agelas tubulata Lehnert & van Soest, 1996: 53; Zea et al. 2009; Messing et al. 2009; Muricy et al. 2011: 40.

Agelas conifera ; Wintermann-Kilian & Kilian 1984: 132; Zea 1987: 212 (in part, only material from Santa Marta see pl. 13, Fig. 1 ). Humann 1992: 22 (in part, only left photo p. 22 and upper photo p. 23); Erhardt & Moosleitner 1995: 78 (in part, only Fig. p. 79); Gómez 2002: 75; Alcolado 2002: 61 (in part); Díaz 2005: 470; Collin et al. 2005: 650.

[Non: Agelas conifera ( Schmidt, 1870) (a valid species)]

Agelas sp.; Goreau & Hartman 1966: 343; Rützler 1978, Fig. 1 a, 3b; Rützler & Macintyre 1982, pl. 4; Erhardt & Moosleitner 1995: 82.

Agelus sp. A and B; Colin 1978, Figs. pg. 57 and 82.

? Agelas sp. 1; Pulitzer-Finali 1986: 113, Fig. 32.

Material and distribution. Holotype examined at the Zoölogisch Museum Amsterdam ( ZMA – POR 11323), collected at Jamaica, Discovery Bay, Long-Term Study Site (LTS), 83.8 m. The material reviewed here includes (but is not restricted to) specimens from the Bahamas (INV– POR 817, INV– POR 935), Jamaica (INV– POR 1008), Belize (INV– POR 949), San Andres Island (INV– POR 979), Rosario Islands (INV– POR 971) and Santa Marta (INV– POR 871).

Other records: Gulf of Mexico (Xahuayxol, Gómez 2002), Florida East coast ( Messing et al. 2009), the Bahamas (Zea et al. 2009), Cuba ( Alcolado 2002), Jamaica ( Goreau & Hartman 1966; Colin 1978), Panama (Díaz 2005; Collin et al. 2005), Old Providence (two specimens mentioned by Zea 1987: 214), San Andrés Island ( Erhardt & Moosleitner 1995), Belize ( Rützler 1978; Rützler & Macintyre 1982), and NE Brazil (to 20° S, Muricy et al. 2011). The species seems absent from Barbados and Curaçao, pending confirmation. From the above, we consider A. tubulata as a tropical western Atlantic species. Our specimens were found at 7–37 m depth, abundant at 10– 18 m.

Description. This species forms single tubes or clusters, fused along their sides ( Fig 8 B), some thin-walled and long (8C, 8H), some stout and robust ( Fig 8 G), arising from a common, generally narrow base ( Fig 8 E); when branching, they usually do so from the base of another tube, and branching is usually not repeated. The whole specimen is 40–60 cm in diameter; each tube can be 20–40 cm high and 3–6 cm in diameter. External colour is orange yellow to reddish or pinskish light brown; internal colour is orange yellow to orange. Surface even, microrugose; pinacoderm rests on tracts of spicules.

Robust specimens can have irregular grooves that may penetrate deep inside the tube wall ( Fig 8 G); there are no oscules on the external surface. Pseudatria 2 to 4 cm in diameter, with a collar-like membrane; oscules (5–15 mm) scattered in the internal wall of the atrium. Consistency of the sponge is elastic, hard to tear and cut. Very hard when dry. The choanosome is dense with narrow channels (<6 mm).

Skeleton with primary fibres cored (0–5 spicules per cross section) and echinated, 60–120 Μm in diameter; secondary fibres echinated, 40–90 µm in diameter. Tertiary fibres are not evident. The acanthostyles are straight with whorls of 5–8 spines; length 84–198 (114±23.7) µm, width 4–11 (6±1.5) µm and 11–24 (15±3) whorls per spicule. Detailed lengths, widths and average number of whorls are shown in Table 2.

Remarks. In Belize and Jamaica the A. tubulata tubes tend to be smooth and long; in San Andres and Rosario Islands they tend to be robust and somewhat grooved. Orange brown to orange-yellow long tubes were early recognized as a species of Agelas , related to but different from A. conifera (see Colin 1978 and Zea 1987). However, intermediate morphotypes also led to the confusion of these two species (e.g., Zea 1987; Gómez 2002; Collin et al. 2005).

In a closer view, characteristics like colour, pinacoderm, skeleton arrangement and spicule architecture, this species is similar to A. cerebrum ( Fig. 14 ), A. conifera and A. sceptrum , which are indeed related species according to molecular phylogeny ( Parra-Velandia, 2011). Indeed, Dr. P.M. Alcolado (pers comm., and see Alcolado 2002) considers A. conifera , A. tubulata and A. cerebrum variations of the same species (see remarks under A. conifera ). We decided to maintain them as separate species until further study. A. tubulata differs from A. cerebrum ( Fig. 14 ) in the general shape ( A. tubulata tubes vs. A. cerebrum barrel/vase-like thickened tubes), smooth and even surface in A. tubulata vs. thoroughly grooved and uneven in A. cerebrum (robust tubes of A. tubulata have grooves, but they are scattered as seen in Fig. 12 G). Compared to A. conifera , the differences are the body size/cone-tube length relation, higher in A. conifera , lower in A. tubulata (for more details see remarks under A. conifera ). A. sceptrum differs from A. tubulata in the presence of tubes in the latter and its complete absence in the former.

Following this model, a photograph presented in Gómez (2002:74, as A. conifera ) clearly shows this species. Zea (1987) mentioned two specimens from Old Providence (N of San Andrés Island) referred by Klaus Rützler to this species when it was still undescribed. Agelas sp. 1 (specimen not seen) as described by Pulitzer-Finali (1986) could belong to A. tubulata . A comparison of specimens should solve the issue.

With respect to colour, the underwater photographs of the holotype show a yellow colour and the description states orange-yellow. In the Bahamas, Belize and Jamaica the colour is amber to yellowish, darker in San Andres Islands and continental South America.

Figures

FIGURE 1. SEM images of Agelas. A) Spicules of A. conifera holotype. B) Spicules of A. clathrodes holotype. C) to D) Fibre skeleton with primary and secondary fibre echination, in A. citrina (C), A. dispar (D, curved fibres) and A. conifera (E). F) Detail of the skeleton of A. conifera showing coring spicules in a broken primary fibre. G) Detail of the skeleton of A. citrina with its long spicules.

FIGURE 8. Photographs of Agelas tubulata. Note the position of oscules with respect to the growing axis plane. A) Holotype at ZMA. B) Jamaica. C) H. Lehnert image from ZMA photographic archives. D) Jamaica. E) Solitary tube, Belize; note the little tube bud at the lower left. F) Detail of the previous specimen. G) Robust tubes with irregular grooves at San Andrés Island, Colombia; note the even surface between grooves. H) Slender group of long tubes at San Andres Island; note predation marks.

FIGURE 12. Photographs of Agelas schmidti. A) Small round, tapered finger from Belize. B) Minute open tubes from Rosario Islands, Colombia. C) Fouled finger, the Bahamas (center only). D and E) Holotype at USNM (courtesy of K. Ruetzler and C. Dietrich).

FIGURE 14. Photographs of Agelas sventres. A) Two small masses, the Bahamas. B) Massive specimen from Curacao; note the surface aspect and the two different kinds of oscules. C) Massive specimen from Jamaica. D) Round, ball specimen from Barbados. E) Holotype from Jamaica (courtesy of J. Xavier).