Paramacrobiotus pius, Lisi, Oscar, Binda, Maria Grazia & Pilato, Giovanni, 2016

Lisi, Oscar, Binda, Maria Grazia & Pilato, Giovanni, 2016, Eremobiotus ginevrae sp. nov. and Paramacrobiotus pius sp. nov., two new species of Eutardigrada, Zootaxa 4103 (4), pp. 344-360: 351-359

publication ID

http://doi.org/10.11646/zootaxa.4103.4.3

publication LSID

lsid:zoobank.org:pub:03887B27-2220-4F28-9889-B39E9789406B

persistent identifier

http://treatment.plazi.org/id/03D087EB-1B54-A71D-C5E0-F957F820FEFB

treatment provided by

Plazi

scientific name

Paramacrobiotus pius
status

sp. nov.

Paramacrobiotus pius   sp. nov.

( Fig. 5 View FIGURE 5 )

Type locality. Gangi (Palermo, Sicily), 37 ° 48 ′00″ N 14 ° 12 ′ 00″E. Former monastery of Gangivecchio (Gangi, Palermo) at 850 m a.s.l.: moss sample collected on rock by Pilato & Binda in August 2002.

Material examined. Holotype (slide no. 5562), 7 paratypes (slides no. 5562 – 3; 5704, 5706– 7), and 10 eggs (slides nos. 5562–5563; 5705–5707); some with fully developed embryos.

Paramacrobiotus pius   sp. nov. No. Slide 5562 paratype 5706

newborn 5704 paratype

5562 holotype 5704 paratype Body length??? 270? Buccal tube length 30.1 30.2 31.1 31.5 34.3 External buccal tube width 5.9 6.1 5.8 6.1 7.3 pt 19.6 20.2 18.6 19.4 21.3 pt stylet supports insertion point 77.7 77.9 76.9 77.2 77.9 First macroplacoid 3.9 4.8 4.4 4.4? pt 13.0 15.9 14.1 14.0? Second macroplacoid 3.1 3.4 3.4 3.6? pt 10.3 11.3 10.9 11.4? Third macroplacoid 4.4 4.3 4.5 4.5? pt 14.6 14.2 14.5 14.3? Microplacoid 2.4 2.3 2.4 2.5? pt 8.0 7.6 7.7 7.9? Placoid row 16.1 16.0 17.4 17.7? pt 53.5 53.0 55.9 56.2? Macroplacoid row 12.5 12.5 13.4 13.2? pt 41.5 41.4 43.1 41.9? External claw I 8.2? 8.7 8.6? pt 27.2? 28.0 27.3? Internal claw I 7.7? 8.5 8.1 8.7 pt 25.6? 27.3 25.7 25.4 External claw II 8.3? 8.9 9.2? pt 27.6? 28.6 29.2? Internal claw II 7.7?? 8.2? pt 25.6 ?? 26.0? External claw III 8.3? 8.9 9.2? pt 27.6? 28.6 29.2? Internal claw III 7.7?? 8.2? pt 25.6 ?? 26.0? Posterior claw IV??? 9.7? pt? ?? 30.8? Anterior claw IV??? 8.9 9.7 pt ??? 28.3 28.3

Specific diagnosis. Colourless; eye spots absent (also in living specimens), cuticle smooth. Bucco-pharyngeal apparatus of the Macrobiotus   type similar to that of Paramacrobiotus richtersi   ; three macroplacoids and a microplacoid (at a distance from the third macroplacoid) present. Well developed claws of the hufelandi   type with accessory points on the main branches and lunules present. Eggs, free laid, with reticulated trunco-conical processes with short terminal thorns; egg shell areolated with clearly sculptured areolae.

Description of the holotype. Body length 270 µm long, colourless; cuticle smooth without pores (only very small dots are present on the legs); eye spots absent; bucco-pharyngeal apparatus of Macrobiotus   type (buccal tube rigid with ventral lamina) ( Fig. 5 View FIGURE 5 A), mouth terminal with 10 peribuccal lamellae; buccal armature composed of an anterior band of small teeth, a posterior ring of small triangular teeth and, more caudally, three dorsal and three ventral transverse ridges. Rigid buccal tube 31.5 µm long and 6.1 µm wide externally (pt = 19.4) ( Table 3); stylet supports inserted on the buccal tube at 77.2 % of its length (pt = 77.2). Pharyngeal bulb with apophyses, three macroplacoids, of almost the same length, and the microplacoid set at a distance from the third macroplacoid, which is a character of the Paramacrobiotus richtersi   group ( Fig. 5 View FIGURE 5 A); first macroplacoid 4.4 µm long (pt = 14.0); second 3.6 µm (pt = 11.4); third 4.5 µm (pt = 14.3); small microplacoid 2.5 µm long (pt = 7.9); the entire placoid row 17.7 µm long (pt = 56.2); the macroplacoid row length 13.2 µm (pt = 41.9). The first macroplacoid does not appear to have a central constriction.

Claws of the Macrobiotus hufelandi   type, well developed, slender, with a long basal portion ( Fig. 5 View FIGURE 5 B,C). External and internal claws of the first pair of legs 8.6 µm long (pt = 27.3) and 8.1 µm long (pt = 25.7) respectively; those of the second and third pairs of legs 9.2 µm long (pt = 29.2) and 8.2 µm (pt =26.0) long respectively ( Table 3); posterior and anterior claws of the hind legs 9.7 µm long (pt = 30.8) and 8.9 µm (pt = 28.3), respectively. Main branches of all claws with thin accessory points ( Fig. 5 View FIGURE 5 B, arrow). Smooth lunules present, well developed on the hind legs ( Fig. 5 View FIGURE 5 C, arrows); a cuticular bar is present near the base of the claws on the first three pairs of legs.

Remarks. The paratypes are similar to the holotype in both morphological and metric characters; the measurements of some structures of the holotype and four paratypes are given in Table 3.

Eggs: The eggs, free laid, are areolated and have trunco-conical processes (10 around the circumference, 21-22 per hemisphere) ( Fig. 5 View FIGURE 5 D). The diameter is 82-88 µm excluding the processes, 105-111 µm including these structures, which are 11.8-12.3 µm high with a basal diameter ca. 20 µm or slightly wider ( Table 4). Short spines are more or less visible on the apices of the processes ( Fig. 5 View FIGURE 5 D). The processes have a reticular ornamentation ( Fig. 5 View FIGURE 5 E) with an elongated mesh (with slightly sinuous margins) near the base, and an isodiametric mesh near the apices; the areolae are sculptured with obvious small tubercles ( Fig. 5 View FIGURE 5 F).

.

Etymology. The name pius   (meaning: holy, devoutly religious) refers to the fact that the population was found in a moss sample collected in the neighbourhood of the ancient former monastery of Gangivecchio (Gangi, Palermo).

Differential diagnosis. As is known, the species of the Paramacrobiotus richtersi   group are all very similar and it is often very difficult to identify them without eggs.

Paramacrobiotus pius   sp. nov. has a smooth cuticle (only very small dots are present on the legs) and therefore differs from Paramacrobiotus corgatensis   (which has very fine dots over dorsal and ventral cuticle) and Paramacrobiotus danielisae   (which has a sculptured cuticle, with small polygons); stylet supports are inserted on the buccal tube in a slightly more cephalic position (pt = 76.9-77.7 in Paramacrobiotus pius   sp. nov., 80.2-80.7 in Paramacrobiotus corgatensis   , 80.2-81.2 in Paramacrobiotus danielisae   ); higher values of the pt index relative to the claw length ( Table 5), and in having conical and shorter egg processes ( Figs. 5 View FIGURE 5 D and 6 A and 6 B). It also differs from Paramacrobiotus corgatensis   in the lack of eye spots.

The new species differs from Paramacrobiotus halei   by having a smooth cuticle, stylet supports inserted on the buccal tube in a slightly more cephalic position (pt = 76.9-77.7 in Paramacrobiotus pius   sp. nov., 81.5 in Paramacrobiotus halei   ) and higher values of the pt index relative to the claw lengths ( Table 5).

The new species differs from Paramacrobiotus savai   , Paramacrobiotus danielae   and Paramacrobiotus peteri   by having higher values of the pt index relative to the claw lengths ( Tables 5 and 6), and by having sculptured egg areolae. In addition, it differs from Paramacrobiotus savai   and Paramacrobiotus danielae   by lacking eye spots, from Paramacrobiotus danielae   by having a smooth cuticle and stylet supports inserted on the buccal tube in a slightly more cephalic position (pt = 76.9-77.7 in Paramacrobiotus pius   sp. nov., 79.9-80.5 in Paramacrobiotus danielae   ); it differs from Paramacrobiotus peteri   also in the shape of the egg processes ( Figs. 5 View FIGURE 5 D and 6 C).

The lack of eye spots distinguishes Paramacrobiotus pius   sp. nov. from Paramacrobiotus priviterae   and Paramacrobiotus sklodowskae   ; in addition, it differs from the former species by the claw shape ( Figs. 5 View FIGURE 5 B,C and 6 D), and from Paramacrobiotus sklodowskae   by a lower value of the pt index relative to the stylet supports insertion point (76.9-77.7 in Paramacrobiotus pius   sp. nov., 81.8-85.2 in Paramacrobiotus sklodovskae   ).

The new species differs from Paramacrobiotus magdalenae   by lacking eye spots, by having higher values of the pt index relative to the claw lengths ( Table 6), and by characters of the eggs (shape of processes and shorter processes).

* According to Michalczyk & Kaczmarek (2006). Slide deposited in the Natural History Collections, Faculty of Biology, A. Mickiewicz University, Poznan, Poland.

** Slide deposited in Te Papa Tongarewa, National Museum of New Zealand, Wellington. ***According to Kaczmarek, Michalczyk and Diduszko, 2005.

Paramacrobiotus pius   sp. nov. differs from Paramacrobiotus alekseevi   by higher values of the pt index relative to the microplacoid length (7.7 –8.0 in Paramacrobiotus pius   sp. nov., 4.0– 6.2 in Paramacrobiotus alekseevi   ), different shape of the egg processes, and egg areolae with more obvious ornamentation.

The new species differs from Paramacrobiotus hapukuensis   by lower values of the pt index relative to macroplacoid lengths but higher values relative to the microplacoid length ( Table 6); slightly higher values of that index relative to the claw lengths ( Table 6); egg processes shorter and different in shape, and sculptured egg areolae ( Figs. 5 View FIGURE 5 D and 7 A).

Paramacrobiotus pius   sp. nov. is very similar to Paramacrobiotus gerlachae   but differs by slightly higher values of the pt index relative to the external claws and a more marked difference in length between external and internal claws on each leg ( Table 6); and overall, in some characters of the egg (small apical spines present, egg areolae with obvious ornamentation, which in comparison is very faint in Paramacrobiotus gerlachae   where the central portion of the areolae is thicker than the periphery) ( Figs. 5 View FIGURE 5 F and 7 B).

The new species differs from Paramacrobiotus vanescens   by having smooth cuticle with small dots only on the legs (the original description of Paramacrobiotus vanescens   did not report that the whole cuticle was finely dotted ( Pilato, Binda & Catanzaro, 1991); however, this characteristic was subsequently stressed by Pilato et al. (2001). In addition, the new species differs from Paramacrobiotus vanescens   by having lower values of the pt index relative to the microplacoid (7.7 –8.0 in Paramacrobiotus pius   sp. nov., and ca. 4 in Paramacrobiotus vanescens   : Figs. 5 View FIGURE 5 A and 7 C), and in details of the eggs (less indented apices of processes, and areolae with more obvious sculpture: Figs. 5 View FIGURE 5 D-F and 7 D).

Paramacrobiotus pius   sp. nov. differs from Paramacrobiotus garynahi   by lacking cuticular pores; by having slightly higher values of the pt index relative to the claw lengths ( Table 6); a different shape of the egg processes, and egg areolae with a more obvious sculpture.

The new species differs from Paramacrobiotus richtersi   overall by having slightly lower values of the index pt relative to the stylet supports insertion point (76.9-77.7 in Paramacrobiotus pius   sp. nov., 79.2-81.8 in Paramacrobiotus richtersi   ), and in some characters of the eggs: the egg processes of the new species have small terminal spines ( Fig. 5 View FIGURE 5 D) whereas in Paramacrobiotus richtersi   they have blunt apices; and the entire surface of the areolae has an obvious reticular sculpture ( Fig. 5 View FIGURE 5 F).

Paramacrobiotus pius   sp. nov. differs from Paramacrobiotus lorenae   by a smooth cuticle, lower value of the pt index relative to the stylet supports insertion point (76.9-77.7 in Paramacrobiotus pius   sp. nov. and ca. 81 in Paramacrobiotus lorenae   ), and in some characters of the eggs (processes with neither elongate nor flexible apices, more evident areolae sculpture).

TABLE 3. Paramacrobiotus pius sp. nov.: Measurements in Μm and pt index values relative to some structures for the holotype and four paratypes.

      Paramacrobiotus pius      
  5562 paratype 5706

newborn 5704 paratype

   
pt stylet supports insertion point            

TABLE 4. Paramacrobiotus pius sp. nov.: Egg measurements (in µm) and number of processes of two eggs. Paramacrobiotus pius sp. nov

Height of the processes up to 11.8 up to 12.3
  21.8–24.7

TABLE 5. Comparative measurements in Μm and pt index values relative to some structures of Paramacrobiotus corgatensis (holotype), Paramacrobiotus danielisae (holotype) Paramacrobiotus halei (paratype), Paramacrobiotus savai (holotype) and Paramacrobiotus danielae (holotype).

  4845 holotype 4940 holotype 5192 paratype 4800 holotype 4728 holotype
pt stylet supports insertion point          

TABLE 6. Comparative measurements in Μm and pt index values relative to some structures of Paramacrobiotus peteri (paratype), Paramacrobiotus magdalenae (holotype), Paramacrobiotus hapukuensis (holotype), Paramacrobiotus gerlachae (paratype) and Paramacrobiotus garynhai (holotype).

    P. magdalenae P. hapukuensis    
  3840 paratype     4864 paratype holotype ***
pt stylet supports insertion point