Dautzenbergia Chevreux, 1900

Zettler, Michael L., Hendrycks, Ed A. & Freiwald, André, 2022, A new amphipod species of the bathyal genus Dautzenbergia Chevreux, 1900 (Amphipoda, Calliopioidea, Pontogeneiidae) associated with cold-water corals off Angola, Zootaxa 5213 (1), pp. 49-63 : 51-62

Genus Dautzenbergia Chevreux, 1900

Dautzenbergia Chevreux, 1900: 73 ; J.L. Barnard 1961: 106; Barnard & Karaman 1991: 316

The generic status of the type species of Dautzenbergia has changed frequently. The species was originally placed in Amphithopsis , then to Sympleustes to Dautzenbergia (by Chevreux 1900). Sexton (1909) moved the species back to Sympleustes with the synonymy of Dautzenbergia to Sympleustes . J.L. Barnard (1961) recognized the non-pleustid form of the lower lip and cleft telson and consequently revived and transferred it back to Dautzenbergia .

Amended diagnosis. (see Barnard & Karaman 1991 and Bellan-Santini et al. 1998). Antenna 1 longer than antenna 2. Accessory flagellum absent or with a minute article. Head with short rostrum. Body dorsally smooth, urosome 2 not shortened. Coxa 1 strongly directed anteriorly, apically pointed. Gnathopods subchelate, grossly unequal (gnathopod 1 much smaller than gnathopod 2), inner margin of dactylus of gnathopod 1 toothed; carpus of gnathopod 1 subequal to propodus, carpus of gnathopod 2 very short, with small short ventral lobe. Pereopods 3–7 dactyls smooth or toothed, pereopods 5–7 homopodous, basis expanded. Labrum bilobed, slightly incised. Labium with inner lobes small or obsolescent. Maxilla 1 inner plate with few terminal setae (2). Maxilla 2 with inner and outer plates subequal. Mandible with strong columnar, triturative molar, palp article 3 long. Maxilliped, palp 4- articulate, powerful with long dactyl. Uropods long, lanceolate, serially spinose, uropods 1–2 rami apices lacking spines, outer rami not strongly shortened. Telson slightly cleft, not ventrally keeled.

Type species. Amphithopsis grandimana Chevreux, 1887: 570–571

Included species. Dautzenbergia includes 5 species: Dautzenbergia grandimana ( Chevreux, 1887) ; Dautzenbergia megacheir ( Walker, 1897) ; Dautzenbergia dentata ( Chevreux, 1919) ; Dautzenbergia comitari ( Myers & Hall-Spencer, 2004) new comb.; Dautzenbergia concavipalma sp. nov.

Key to Dautzenbergia species

1. Pereopods 3–7, dactyls toothed.......................................................................... 2

- Pereopods 3–7, dactyls smooth.......................................................................... 3

2. Gnathopod 1, propodus narrow, length 2.6 x width; gnathopod 2, propodus posterior margin shorter than palm, palm straight, strongly setose; epimeron plate 3, weakly subquadrate, without posteroventral cusp; telson, oval, length 1.4 x width, split 15 % of length, lobes rounded, without distal inset spine.......................... D. comitari ( Myers & Hall-Spencer, 2004)

- Gnathopod 1, propodus broad, length 1.6 x width; gnathopod 2, propodus posterior margin subequal to palm, palm evenly convex, lined with small spines; epimeron plate 3, posteroventral corner with a small cusp; telson, subtriangular, length ~ 2 x width, split 9 % of length, lobes slightly angular, with small distal inset spine............ D. grandimana ( Chevreux, 1887)

3. Gnathopod 2, propodus dorsal margin strongly convex, length 3.36 x width (female 2.6 x), palm strongly concave and setose, occupying nearly the complete length of the propodus, with a strong tooth at the posteroproximal corner and posterodistal margin with a strong, flanged cusp near insertion of dactylus; pereopod 7, basis broad, length 1.4 x width; telson, length 1.4 x width, split 17 % of length........................................................... D. concavipalma sp. nov.

- Gnathopod 2, propodus dorsal margin slightly convex, length 1.8–2.6 x width, palm not occupying the complete length of the propodus, palm not strongly setose, lacking a tooth at posteroproximal corner; pereopod 7, basis narrower, length> 1.5 x width; telson, length> 1.7 x width, split> 20 % of length........................................................... 4

4. Gnathopod 2, propodus palm concave proximally, slightly setose, distal half of palm with 3 tubercles, the first rounded and followed by a deep sinus; pereopod 7, basis length 1.8 x width; telson, length 2.1 x width, split 25 % of length, lobes rounded, lacking distal inset spine.......................................................... D. dentata ( Chevreux, 1919)

- Gnathopod 2, propodus palm nearly straight proximally, spinose, distal half of palm with 2 tubercles, the first broadly rectangular and preceded by a deep sinus; pereopod 7, basis length 1.5 x width; telson, length 1.8 x width, split 20–25 % of length, lobes pointed, with fine distal inset spine................................................. D. megacheir ( Walker, 1897)