Paracaprella carballoi sp., 2014

Sánchez-Moyano, J. E., García-Asencio, I. & Guerra-García, J. M., 2014, Littoral caprellids (Crustacea: Amphipoda) from the Mexican Central Pacific coast, with the description of four new species, Journal of Natural History 49 (1), pp. 77-127 : 108-115

Paracaprella carballoi sp. nov.

( Figures 19–22 )

Type material

Holotype male plus 5 slides ( MNCN 20.04 /9231) , Allotype female ( MNCN 20.04 / 9232) . Paratypes: 2 males ( MNCN 20.04 /9233-34) , 4 females ( MNCN 20.04 / 9235-38) .

Additional material examined

St1: 20 males, 19 females, 15 juveniles.

Type locality

Isla de los Pájaros (Mazatlán), México, 3–6 m, on the seaweed Zonaria cf. farlowii with epiphytic hydroids.

Etymology

The species is dedicated to Dr José Luis Carballo for his important contribution to the knowledge of the benthic fauna from the Pacific coast of México.

Diagnosis

Head rounded. Pereonite 2 with a rounded and narrow anteroventral projection in adult males, absent in females. Mandibles with molar process and palp reduced to a long seta. Flagellum of antenna 1 nine-articulate. Propodus of gnathopod 2 palm with rectangular projection proximally, carrying two proximal grasping spines and a distal robust tooth. Pereopod 3 and 4 two-articulate. Pereopod 5–7 without grasping spines. Abdomen with a pair of setose uni-articulate appendages.

Description

Male holotype. Body length: 5 mm.

Lateral view ( Figure 19 ): Head rounded. Pereonite 1 fused with head, suture present. Body dorsally smooth, except anterodorsal blunt protuberance on pereonite 2 (absent in immature males). Pereonite 2 with a rounded and narrow anteroventral projection. Pereonite 3 the longest. Pereonite 7 the shortest.

Gills ( Figure 19 ): Present on pereonites 3–4, oval. Gills on pereonite 3 about twice as long as those on pereonite 4.

Mouthparts ( Figure 20 ): Mandibles with molar process and palp reduced to a long seta; incisor and lacinia mobilis five-toothed; left and right mandibles with three and two pectinated setae, respectively. Maxilla 1 outer lobe carrying six robust-stout setae; distal article of the palp with three robust-stout setae and three marginal setae. Maxilla 2 inner lobe oval, carrying four distal setae, and outer lobe elongated, with five apical setae. Maxilliped inner plate rectangular carrying three setae apically; outer plate with six submarginal and two apical setae; palp four-articulate, setose; third article provided with a large distal process and setose apically; terminal article with a row of setulae on grasping margin, and one seta subdistally. Upper and lower lip lost in dissection.

Antennae ( Figures 19 and 21 ): Antenna 1 shorter than the combined lengths of head and pereonite 2–3. Peduncle scarcely setose; flagellum nine-articulate. Antenna 2 a little shorter than peduncle of antenna 1; proximal peduncular article with a small acute projection distally; swimming setae absent; flagellum two-articulate, proximal article c. 2.5 times the length of the distal one.

Gnathopods ( Figure 21 ): Gnathopod 1 basis as long as ischium, merus and carpus combined; propodus palm with a single proximal grasping spine; grasping margin of propodus serrated with setae; distal ventral margin of dactylus with one tooth. Gnathopod 2 inserted on the anterior half of pereonite 2; basis elongated slightly shorter than pereonite 2, with two distal short processes on lateral margin; propodus length about twice width; propodus palm with rectangular projection proximally, carrying two proximal grasping spines and a distal robust tooth; grasping margin setose; dactylus thickened medially and setose.

Pereopods ( Figures 19 and 22 ): Pereopod 3 and 4 two-articulate, both with four setae apically on distal article and two setae subdistally on basal article. Pereopod 5–7 increasing in length, six-articulate and attached to the posterior end of the pereonite, with several plumose setae. Palm of propodus of pereopod 5 with a proximal short knob bearing a small spine; palm of pereopod 6–7 with several proximal short knobs, each bearing a small spine. Grasping spines absent.

Penes ( Figure 22 ): Penes short, situated laterally.

Abdomen ( Figure 22 ): A pair of setose uni-articulate appendages, a pair of lateral lobes, and a single dorsal lobe.

Allotype female. Body length: 4.4 mm. Similar to male except for the following morphological characteristics ( Figures 19 and 21 ): oostegites present, being slightly setose on pereonite 3 and 4; anterolateral projection on pereonite 2 absent; flagellum of antenna 1 eight-articulate; propodus of gnathopod 2 oval, with a proximal knob bearing a grasping spine, dactylus not setose. Abdomen with a pair of lateral lobes and single dorsal lobe carrying two setae ( Figure 22 ).

Habitat

Paracaprella carballoi was mainly found attached to the seaweed Zonaria cf. farlowii with abundant small hydroids on underside of thallus, between 3–6 m depth. On these substrates it was relatively abundant. Also it has been found on the gorgonian Leptogorgia rigida , although in low densities. Other caprellids on these substrates were Aciconula acanthosoma , Caprella mendax , C. pitu and Liropus isabelensis .

Distribution

Paracaprella carballoi has been found so far from the type locality, Isla de los Pájaros (Mazatlán), México .

Figures

Figure 19. Paracaprella carballoi sp. nov. Lateral view, holotype male and allotype female. Scale bar: 1 mm.

Figure 20. Paracaprella carballoi sp. nov. Holotype male mouthparts. Scale bar: 0.05 mm.

Figure 21. Paracaprella carballoi sp. nov. Holotype male antennae, gnathopod 1 and 2. Allotype female gnathopod 2. Scale bar: x (Gn1-2): 0.4 mm; y (A1, A2): 0.2 mm.

Figure 22. Paracaprella carballoi sp. nov. Holotype male pereopods 3–7 and abdomen. Allotype female abdomen. Scale bar: x (P3-4): 0.05 mm; y (Ad): 0.05; z (P5-7): 0.1 mm.