Dispio bescanzae, Delgado-Blas, Víctor Hugo & Díaz-Díaz, Oscar, 2016
|
publication ID |
https://doi.org/ 10.11646/zootaxa.4178.2.1 |
|
publication LSID |
lsid:zoobank.org:pub:C533EE2A-5831-49A2-A4ED-2E7CD94EC663 |
|
DOI |
https://doi.org/10.5281/zenodo.5661065 |
|
persistent identifier |
https://treatment.plazi.org/id/CA1187AD-CA44-E859-FF30-A738DEA1FD12 |
|
treatment provided by |
Plazi |
|
scientific name |
Dispio bescanzae |
| status |
sp. nov. |
Dispio bescanzae View in CoL sp. nov.
( Figure 5 View FIGURE 5 A–Z)
Material examined. Atlantic coast of Venezuela, Güiria , 10º33′58″N, 62º44′21″W, shallow subtidal, soft bottom, 0.015 m 2 PVC corer, coll. Oscar Díaz-Díaz, March, 2006, holotype ( ECOSUR 0178 View Materials ); same data for seven paratypes ( ECOSUR 0179 View Materials ). Non type material: 12 specimens ( MOBR I-1270) from El Peñon, Sucre state GoogleMaps , Venezuela 10º27′02″N, 64º05′21″W, very fine sand 0.5 m of deep, 0.015 m 2 PVC corer, coll. Oscar Díaz-Díaz, March 2014 GoogleMaps ; 21 specimens (CB OM-UC 105) from El Peñón, very fine sand 0.5 m deep, 0.015 m 2 PVC corer, coll. Oscar Díaz-Díaz, February 2015.
Description. Holotype incomplete, anterior fragment with 77 chaetigers, 26 mm long, 1.0 mm wide at chaetiger 15. Complete paratypes with 38–188 chaetigers (longest specimen in five fragments) plus 1–3 final segments with no chaetae; 8.0– 49 mm long, 0.7–1.3 mm wide at chaetiger 15; incomplete paratypes with an anterior fragment with 36–89 chaetigers, 6.0– 28 mm long, 0.7–1.0 mm wide at chaetiger 15. Color in alcohol yellowish white.
Prostomium hourglass-shaped, widest subterminally, bluntly pointed on anterior margin ( Fig. 5 View FIGURE 5 A–B), posteriorly tapered, with a long, triangular, raised, caruncle ( Fig. 5 View FIGURE 5 A–C) to end on posterior margin of chaetiger 1 ( Fig. 5 View FIGURE 5 A–C). With two pairs of subdermal, black eyes, arranged in a straight line ( Fig. 5 View FIGURE 5 A): one pair of small, lateral, kidney-shaped eyes and one pair of rounded, medial eyes, or arranged in a trapezoid, first pair rounded, and posterior pair reniform ( Fig. 5 View FIGURE 5 B) (eyes not observed in holotype). Peristomium long, collar-like, surrounding prostomium, separated from chaetiger 1, forming moderate lateral wings ( Fig. 5 View FIGURE 5 A–C). Proboscis not observed. Palps short ( Fig. 5 View FIGURE 5 B, C) extending to chaetigers 3–10 (chaetiger 5 in holotype); palps with single band of transverse rows of cilia on one side of ventral ciliated groove. Palp sheaths large, smooth, fused to base of palps ( Fig. 5 View FIGURE 5 B).
Notopodial postchaetal lamellae of chaetigers 1–2 shifted dorsally and deeply serrated. Lamellae of chaetiger 1 bearing 4 – 9 (7 in holotype) digitiform papillae along distal and middle margins ( Fig. 5 View FIGURE 5 A–B, D), basal margin rounded ( Fig. 5 View FIGURE 5 D). Notopodial lamellae of chaetiger 2 with 8 – 11 (8 in holotype) digitiform papillae along margin ( Fig. 5 View FIGURE 5 A, E); lamellae of chaetigers 3 – 6 with 6 – 10 (6 – 7 in holotype) digitiform papillae ( Fig. 5 View FIGURE 5 A, F) along margin; lamellae of chaetiger 7 with 1–8 (2 in holotype) digitiform papillae along margin ( Fig. 5 View FIGURE 5 A, G); lamellae of chaetigers 8 – 10 with up to 5 digitiform papillae, although some specimens with lamellae on chaetigers 8/11 – 37/44 (8–37 in holotype) with ruffled margin ( Fig. 5 View FIGURE 5 H); lamellae of chaetigers 37 – 44 and subsequent chaetigers with pointed ventral border ( Fig. 5 View FIGURE 5 H–J). Ventral and dorsal edges of notopodial and neuropodial lamellae overlapping or touching only on posterior chaetigers ( Fig. 5 View FIGURE 5 I–J, L). Notopodial prechaetal lamellae, small, subtriangular on chaetigers 1 – 2 (Fig. D–E), thereafter increasing in size, wider, continuing through anterior chaetigers and around chaetiger 43 becoming slender, long and triangular (Fig. I, J), thereafter diminishing in size through posterior chaetigers. Each segment with a pair of dorsal J-shaped double bands of cilia arranged obliquely with a transverse band of cilia between them ( Fig. 5 View FIGURE 5 K). Lateral organs between notopodial and neuropodial postchaetal lamellae visible but small on middle chaetigers ( Fig. 5 View FIGURE 5 L).
Neuropodial postchaetal lamellae of chaetigers 1–3 serrated and shifted dorsally. Neuropodial lamellae of chaetiger 1 with 1 – 5 (1–5 in holotype) digitiform papillae along margin ( Fig. 5 View FIGURE 5 D), lamellae of chaetigers 2 – 3 with 1 – 5 (1–4 in holotype) digitiform papillae ( Fig. 5 View FIGURE 5 E–F), lamellae of chaetigers 4 – 28/39 rounded and smooth ( Fig. 5 View FIGURE 5 G) (one specimen with 2 digitiform papillae on right lamellae from chaetiger 4), later becoming wider on chaetigers 29 – 40 (38 in holotype) forming a pointed upper border ( Fig 5 View FIGURE 5 H–I), gradually diminishing in size on subsequent chaetigers ( Fig. 5 View FIGURE 5 J). Neuropodial prechaetal lamellae small, rounded and wide ( Fig. 5 View FIGURE 5 D–F); larger in mid region but decreasing gradually in size on posterior chaetigers ( Fig. 5 View FIGURE 5 J). All neuropodial prechaetal lamellae not basally fused with neuropodial postchaetal lamellae.
Branchiae present from chaetiger 1 ( Fig. 5 View FIGURE 5 B, D) to end of body ( Fig. 5 View FIGURE 5 J); branchiae tapered, elongate, smooth; fused along length of notopodial lamellae, branchial tips free, distally pointed on all anterior chaetigers and slightly longer than notopodial lamellae ( Fig. 5 View FIGURE 5 D–F). Branchiae on middle and posterior chaetigers smaller than notopodial lamellae ( Fig. 5 View FIGURE 5 I–J). Each branchia with a band of cilia along inner edge. Accessory branchiae present from chaetigers 13 – 30 (16 in holotype), initially with a single, short digitate lobe that arises from dorsolateral side of body behind notopodial base, with number of lobes increasing to seven in posterior chaetigers ( Fig. 5 View FIGURE 5 M) arranged in two rows.
Notochaetae of chaetiger 1 arranged in a dorsal tuft and a ventral fascicle; dorsal tuft with about 30 to 40 very long, slender ( Fig. 5 View FIGURE 5 A, C), alimbated, smooth capillaries ( Fig. 5 View FIGURE 5 N) directed upwards ( Fig. 5 View FIGURE 5 A, C), longer than ventral fascicle; ventral fascicle arranged in two rows; anterior row comprised of stout, moderately reticulated, granulated, unilimbated capillaries ( Fig. 5 View FIGURE 5 O), and posterior row of slender, smooth, alimbated capillary chaetae ( Fig. 5 View FIGURE 5 P), longer than chaetae of anterior row, and less numerous than those comprising dorsal tuft. Notochaetae of chaetiger 2 and subsequent chaetigers arranged in three groups; first group with 2 or 3 uppermost wider, smooth, alimbated, capillaries, diminishing gradually in size and number to an anterior row of stout moderate reticulated, granulated, unilimbated capillaries ( Fig. 5 View FIGURE 5 Q), and a posterior row of slender, very slightly granulated, unilimbated capillaries ( Fig. 5 View FIGURE 5 R), longer than those of anterior row. Middle chaetigers with same structure of anterior chaetae except for an anterior row of reticulated, long, slightly bilimbate, very pointed capillaries ( Fig. 5 View FIGURE 5 S). Posterior chaetigers with dorsal tuft of slender, long, smooth, distally unilimbated capillaries ( Fig. 5 View FIGURE 5 T), and posterior row of slender, smooth, alimbated capillaries. Notopodial hooded hooks absent.
Neurochaetae of chaetiger 1 similar to notochaetae of chaetiger 1, arranged in two rows: an anterior row of stout, moderate, reticulated, granulated, unilimbate capillaries ( Fig. 5 View FIGURE 5 U), and a posterior row of shorter, slender, unilimbate, smooth capillary chaetae ( Fig. 5 View FIGURE 5 V), capillaries of anterior row shorter than those of posterior row; in addition, a ventral tuft of 4 – 5 shorter, slender, smooth, alimbated capillaries located in position of sabre chaetae. Chaetigers 2–9 similar to chaetiger 1 but with long, reticulated, slightly granulated, alimbated sabre chaetae; on chaetigers 10 – 15 (11 in holotype) sabre chaetae longer, stouter, heavily reticulated ( Fig. 5 View FIGURE 5 W), 2 – 3 per fascicle. Unidentate neuropodial hooded hooks ( Fig. 5 View FIGURE 5 X–Y) (one specimen with one bidentate hook on a posterior fascicle) replacing anterior row of capillary neurochaetae from chaetigers 20 – 27, up to six per neuropodium, accompanied by a row of smooth, slender, unilimbated capillary chaetae ( Fig. 5 View FIGURE 5 Y). Hooded hooks distally entire, slightly curved and hood extended distally to, or slightly beyond tip ( Fig. 5 View FIGURE 5 X–Y).
Pygidium with midventral flap and two long cirri ( Fig. 5 View FIGURE 5 Z).
Remarks. Dispio bescanzae sp. nov. is very similar to D. uncinata and D. panamensis sp. nov. Dispio bescanzae sp. nov and D. uncinata have branchiae of the same length and similarly shaped anterior postchaetal notopodial and neuropodial lamellae on the first three chaetigers, all serrated. However, Dispio bescanzae sp. nov. can be distinguished from the type material of D. uncinata , in that the former has a hourglass-shaped prostomium without lateral emarginations, notopodial lamellae on chaetigers 4 – 7/10 with digitiform papillae along margin, lamellae of chaetigers 8/11 – 37/44 with ruffled margin, lamellae of chaetigers 37 – 44 and subsequent chaetigers with pointed ventral border, ventral and dorsal edges of notopodial and neuropodial lamellae overlapping or touching only on posterior chaetigers, neuropodial lamellae of chaetigers 4 – 28/39 rounded and smooth, a pair of dorsal J-shaped double bands of cilia, anterior notopodial chaetae on posterior row with smooth, alimbated capillary chaetae, anterior neuropodial chaetae on anterior row with unilimbate capillaries, a posterior row of shorter, unilimbate, smooth capillary chaetae, hooded hooks slightly curved and sub-distally entire, the hoods open and extend distally or slightly beyond the tip of the hook. Dispio bescanzae sp. nov. is similar to D. panamensis sp. nov. in having deeply serrated anterior notopodial and neuropodial lamellae with papillae, a short caruncle, peristomium of the same length and lateral wings. However, D. bescanzae sp. nov. differs from D. panamensis sp. nov. in that the former has a hourglass-shaped prostomium, bluntly pointed anteriorly, a long, triangular caruncle, branchial tips distally pointed on all chaetigers, and the notopodial and neuropodial lamellae overlapping on posterior chaetigers.
In this species we observed one bidentate hooded hook on the posterior chaetiger of one adult specimen. See remarks about bidentate hooks in D. lenislamellata sp. nov. Further differences between this new species and the other species examined are provided in the key and Table 1.
Etymology. This species is named after Díaz-Díaz’s mother-in-law, who recently passed away, and is dedicated to her and all the women in the Bescanza family.
Type locality. Güiria , Venezuela.
Ecology. Specimens were collected in shallow water (1.5 m deep) in fine, medium and coarse sands.
Geographical distribution. Venezuela (Güiria and El Peñón).
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.