Deutella mayeri Stebbing, 1895

Paz-Ríos, Carlos E., Guerra-García, José M. & Ardisson, Pedro-Luis, 2014, REVIEW ARTICLE Caprellids (Crustacea: Amphipoda) from the Gulf of Mexico, with observations on Deutella mayeri, redescription of Metaprotella hummelincki, a taxonomic key and zoogeographical comments, Journal of Natural History 48 (41 - 42), pp. 2517-2578 : 2534-2538

Deutella mayeri Stebbing, 1895

( Figures 6–8 )

Deutella mayeri Stebbing, 1895: 400–402 , pl. 15a. Mayer, 1903: 44–45. McCain, 1968: 54–57, figs 25, 26, 52. McCain and Steinberg, 1970: 48. Ortiz et al., 2002, fig. 30. Guerra-García, 2003b: 1070–1071, fig. 8. Guerra-García, Krapp-Schickel, et al., 2006: 168–171, figs 12, 13.

Material examined

Station 10, two males (one male from this station used for figures, male A; the other male used for figure Gn2″, male B), 17 September 2007, CYMX-11- CY . Station 21, one male, 21 May 2010, CYMX-28- CY . Station 23, one male, two females (1 ovigerous), 22 May 2010, CYMX-29- CY ; one male, two females, 21 July 2010, CYMX-39- CY . Station 24, one male, 18 May 2010, CYMX-27- CY ; one male, 18 June 2010, CYMX-30- CY . Station 27, one male (gnathopod 2 used for figure Gn2′, male C), three females (two ovigerous; one female from this station used for figures), CYMX-34- CY .

Type locality

Antigua, West Indies .

Distribution

Gulf of Mexico; Caribbean Sea ( McCain 1968; Ortiz and Lalana 1996, 2010; Guerra- García 2003b; Guerra-García, Krapp-Schickel, et al. 2006).

Records in the Gulf of Mexico

MEX: Celestun; Celestun Offshore; Sisal Offshore (present study). USA: Southwestern Florida ( Guerra-García 2003b).

Habitat

This species has been found clinging on Thallassia sp., hydroids, algae (Guerra- García, Krapp-Schickel, et al. 2006) and on sandy bottoms from coral reef areas as

well as on muddy sediment from the coast (present study). The depth range is 1–18 m ( Guerra-García 2003b; present study).

Ontogenetic development

The main feature to distinguish this species easily from the remaining species of Deutella is in the striking propodus of gnathopod 2 in males: it has a triangular elongate process proximally provided with a grasping spine ( Guerra-García 2003b). Regarding that, Guerra-García, Krapp-Schickel, et al. (2006) illustrated the morphological variation in the propodus of gnathopod 2 in the male of D. mayeri during its development. In the present study, though only a few specimens were examined, the morphological variation of gnathopod 2 was also observed. In fact, the propodus of the male specimen is stouter and larger than those illustrated by McCain (1968); Guerra-García (2003b) and Guerra-García, Krapp-Schickel, et al. (2006), suggesting a final stage of development, a superadult. Furthermore, based on the material examined, the morphological variation during the development of D. mayeri can also be noticed on the anterolateral projection of pereonites 2 and 3 (rounded when superadult instead of triangular when juvenile or adult), and dorsal surface of pereonite 2 (two pairs of tubercles when superadult instead of smooth when juvenile or adult).

Other morphological characters that also varied with development, and which contrast with the descriptions and observations of McCain (1968) and Guerra-García (2003b) were displayed in the mouthparts, specifically in the maxilla 1–2, and maxilliped. Outer lobe of maxilla 1 bearing seven distal spines (new range: 4–7). Outer lobe of maxilla 2 with nine apical setae (new range: 5–9); inner lobe with eight apical setae (new range: 4–8). Inner plate of maxilliped with 3–7 apical setae of which 1–4 robust and 2–3 plumose, and one robust, short seta like a ‘tooth’.

Remarks

A characteristic observed in the material examined and not reported before for D. mayeri was the uni-articulate pereopod 3 and 4. Usually these pereopods have been described and illustrated with two articles, therefore the present material denotes intraspecific variation in D. mayeri .

The male of D. mayeri is similar to that of Deutella indica Guerra-García, 2002c by the shape of gnathopod 2, but differ by the two pairs of dorsal tubercles on pereonite 2, a simple setal formula and the uni-articulate abdominal appendage. Likewise, D. mayeri is similar to Deutella caribensis Guerra-García , Krapp- Schickel, et al. 2006, Deutella philippinensis Guerra-García, 2002d and Deutella venenosa Mayer, 1890 , the others species of the genus bearing one article on pereopods 3 and 4. Deutella mayeri differs from the first species by the head and pereonites 3 and 4 smooth, and mandibles with setal formula simple; it differs from the second species by the mandibles with setal formula simple, dorsal tubercles on pereonite 2 and male abdomen appendages uni-articulate; it differs from the third species by the head and pereonite 1 smooth, and dorsal tubercles on pereonite 2.

Reports on the occurrence of D. mayeri in the Gulf of Mexico have been occasional and confusing. Ortiz (1979) based on Steinberg and Dougherty (1957) included this species in a checklist of amphipods for the Gulf of Mexico and Caribbean Sea. After that, Posey et al. (1998) in an ecological study reported this species occurring on sandy sediments of the northwestern continental shelf from Florida. More recently Escobar-Briones et al. (2002) included this species in their checklist of amphipods for Mexico; however, the most recent checklist for Mexico made by Winfield (2008) did not include D. mayeri . In a review of the genus Deutella, Guerra-García (2003b) confirmed the record of D. mayeri in the Gulf of Mexico, which was adopted by Winfield and Ortiz (2013) in their checklist of caprellids for the Gulf of Mexico.

Figures

Figure 6. Deutella mayeri Stebbing, 1895. Yucatan, Mexico; male A, CYMX-11-CY; female, CYMX-34-CY. Scale bar for A1 and A2: 0.5 mm; scale bar for male A and female: 1 mm.

Figure 7. Deutella mayeri Stebbing, 1895. Yucatan, Mexico; male A, CYMX-11-CY. Scale bar: 0.1 mm.

Figure 8. Deutella mayeri Stebbing, 1895. Yucatan, Mexico; male A and male B, CYMX-11- CY; male C and female, CYMX-34-CY. Scale bars for P3, P4, AbDv and AbDv of female: 0.1 mm; scale bars for Gn1, Gn1 of female and Gn2 of female: 0.2 mm; scale bar for Gn2 of male A, Gn2′ of male C and Gn2″ of male B: 0.5 mm.