Protoaeginella verrucosa, Guerra-García, 2004
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publication ID |
https://doi.org/ 10.5281/zenodo.5393370 |
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persistent identifier |
https://treatment.plazi.org/id/03853225-FFBD-7E21-CF9B-C9E4FC91AABF |
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treatment provided by |
Marcus |
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scientific name |
Protoaeginella verrucosa |
| status |
sp. nov. |
Protoaeginella verrucosa View in CoL n. sp.
( Figs 12-15 View FIG View FIG View FIG View FIG )
TYPE MATERIAL. — Holotype: stn 64, (MNHN- Am 5254). Allotype: stn 64, (MNHN-Am 5255). Paratypes: stn 126, 1 (MNHN-Am 2947), and stn 64, 4, 9 (MNHN-Am 5256).
ETYMOLOGY. — The specific name is descriptive of the numerous small tubercles on the body.
DISTRIBUTION. — So far, only known from the Azores.
DESCRIPTION
Holotype, male (6.9 mm)
Lateral view ( Fig. 12A View FIG ). Body densely covered with numerous small tubercles. Eyes absent but there is an indistinct ocular spot. Pereonite 1 fused with head although the suture between them is very distinct. Pereonites 2 to 5 increasing in length. Pereonites 4 and 5 curved. Pereonite 7 the shortest.
Gills ( Fig. 12A View FIG ). Present on pereonites 3-4, elongate, length about four times width.
Mouthparts. Upper lip ( Fig. 13E View FIG ) symmetrically bilobate, without setullae apically. Mandibles ( Fig. 13B, C View FIG ) with three-articulate palp; distal article of palp with a row of five setae on left mandible ( Fig. 13C View FIG ) and three setae on the right mandible ( Fig. 13B View FIG ); mandibular molar present, strong; incisor five-toothed in both mandibles; left mandible with lacinia mobilis five-toothed followed by a row of three setae; right mandible with lacinia apparently four-toothed, although irregularly dentate, followed by two plumose setae; molar flake present in right mandible, elongate. Lower lip ( Fig. 13D View FIG ) inner and outer lobes well demarcated, without setulae; inner lobes rounded. Maxilla 1 ( Fig. 13F View FIG ) outer lobe carrying seven spiniform setae; distal article of the palp with four robust setae apically and one plumose seta medially. Maxilla 2 ( Fig. 13G View FIG ) inner lobe rectangular, carrying five setae distally; outer lobe rectangular, 1.2 times as long as inner lobe, with eight apical setae. Maxilliped ( Fig. 13A View FIG ) inner plate carrying two nodular setae (short and robust, like a tooth), and four plumose setae; outer plate oval, 1.8 times as long as inner plate, with two or three nodular setae, one distal apical simple seta and one simple lateral seta; palp four-articulate, second and third article setose.
Antennae. Antenna 1 ( Fig. 14A View FIG ) about one sixth of body length; distal article of the peduncle provided with a small accessory flagellum which carries two distal setae; flagellum seven-articulate. Antenna 2 ( Fig. 14B View FIG ) without swimming setae; proximal peduncular article with acute distal projection; flagellum two-articulate, setose.
Gnathopods. Gnathopod 1 ( Fig. 14C View FIG ) basis a little longer than ischium to carpus combined; propodus palm with a pair of grasping spines proximally; grasping margin of propodus palm with small setulae on the anterior half; dactylus serrate. Gnathopod 2 ( Fig. 14D View FIG ) inserted on the anterior half of pereonite 2 ( Fig. 12A View FIG ); basis 0.7 times as long as pereonite 2, with rows of tubercles; ischium rectangular; merus rounded; carpus short and triangular; propodus elongate, almost as long as basis; palm with proximal projection provided with a single spine, followed by another projection medially and scarcely serrate margin on distal half; dactylus with smooth margin, provided with a row of tiny setulae.
Pereopods. Pereopods 3, 4 and 5 absent; a tiny knob without setae instead of the pereopod 5 ( Fig. 12A View FIG ). Pereopods 6 and 7 missing in male holotype ( Fig. 12A View FIG ) described from a male paratype (MNHN-Am 5256). Pereopod 6 ( Fig. 15A View FIG ) attached to the posterior end of the pereonite 6, six-articulate, basis without carina, ischium short and rectangular; merus and carpus palm carrying row of fine setae; propodus palm with a row of robust acute setae. Pereopod 7 ( Fig. 15B View FIG ) similar to pereopod 6.
Penes ( Fig. 15C View FIG ). Penes large and wide, almost as long as wide, situated laterally.
Abdomen ( Fig. 15C View FIG ). Abdomen with indistinct dorsal suture line, apparently two-segmented. Two pairs of appendages. The first pair apparently two-articulate; distal article three times as long as the proximal article, with a seta medially and ending in minute spines. Second pair of appendages smaller, one-articulate, with one medial seta and ending in minute spines. Lateral lobes with a big seta and dorsal lobe with two plumose setae.
Allotype, female (4.8 mm)
Oostegites 3 and 4 setose ( Fig. 12B View FIG ). Genital papillae ( Fig. 12B View FIG ) with a seta medially. Basis of gnathopod 2 with few tubercles; palm of gnathopod 2 without the projection medially and not distally serrated ( Fig. 12E View FIG ). Abdomen ( Fig. 15D View FIG ) also with two pairs of appendages, as in the male. REMARKS
The body length measured for the males of P. verrucosa n. sp. was 6.50 ± 0.54 mm (mean ± standard deviation) (range 5.83-7.21 mm). For the females it was 4.58 ± 0.32 mm (4.00- 5.01 mm). In connection with the intraspecific variation, the morphological characters of antennae, mouthparts, gnathopods, pereopods and abdomen are constant in all the specimens examined, except for the setal formula of the mandibular palp (1-x-1) where “x” can be 1, 2 or 3. Furthermore, the number of robust setae distally in the palp of the maxilla 1 can be three or four.
The new species Protoaeginella verrucosa n. sp. superficially resembles P. muricata described by Laubitz & Mills (1972); the lateral view is extremely similar due to the presence of abundant small tubercles on the body. Nevertheless, both species can be easily distinguished by checking the abdomen which is very different in both species. The abdomen is five-segmented in P. muricata , bearing only a pair of minute appendages ( Laubitz & Mills 1972), whereas it is two-segmented in P. verrucosa n. sp., bearing two pairs of appendages. According to the presence of two pairs of appendages in the male and female abdomen, we could justify the erection of a new genus for P. verrucosa n. sp., since the remaining species of Protoaeginella have only one pair of appendages. However, although the abdomen of P. muricata and P. spinipoda are different enough to consider two different genera, Laubitz & Sorbe (1996) preferred to consider both species in the same genus based on the similarities in antennae, pereonites, pereopods and mouthparts. In the case of P. verrucosa n. sp. we have also considered it in the genus Protoaeginella mainly based on the presence of accessory flagellum in antenna 1 and absence of pereopods 3, 4 and 5.
As far as it is known, there are only two other caprellid genera which have the accessory flagellum on antenna 1, Parvipalpina Stephensen, 1944 and Protellina Stephensen, 1944 . In these two genera, pereopod 5 is present (although very reduced in Parvipalpina ) whereas it is absent in Protoaeginella ( Stephensen 1944) .
So far, the genus Protoaeginella is restricted to deep waters of the North Atlantic ( Laubitz & Mills 1972; Laubitz & Sorbe 1996; present study).
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.