The ammonoids from the Gattendorfia Limestone of Oberrödinghausen (Early Carboniferous; Rhenish Mountains, Germany) Author Korn, Dieter 286CA4F3-7EBC-4AEF-A66A-B2508D001367 Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstrasse 43, 10115 Berlin, Germany. dieter.korn@mfn.berlin Author Weyer, Dieter A09A1738-C70E-4F22-A069-8B7DB4A1753D Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstrasse 43, 10115 Berlin, Germany. dieter.weyer@t-online.de text European Journal of Taxonomy 2023 2023-07-19 882 1 230 http://dx.doi.org/10.5852/ejt.2023.882.2177 journal article 58033 10.5852/ejt.2023.882.2177 57d1d191-2bf5-4229-a0f5-9ab472a114a6 2118-9773 8177581 67C909E4-C700-4F8D-B8CE-5FD9B2C5D549 Zadelsdorfia zana sp. nov. urn:lsid:zoobank.org:act: 8ABDDAC1-F889-4E3B-8F43-00DCB44E17CA Tables 81–82 Gattendorfia crassa – Bockwinkel & Ebbighausen 2006: 109 , text-figs 26, 27g –j. Diagnosis Species of Zadelsdorfia with a thickly discoidal, very evolute conch at 5 mm dm (ww/dm ~0.50; uw/ dm ~0.62); conch at 15 mm dm thinly pachyconic, subevolute (ww/dm ~0.65; uw/dm ~0.35). Whorl profile in the juvenile stage crescent-shaped, at 20 mm dm weakly depressed (ww/wh ~1.45); coiling rate moderately high (WER ~1.85). Venter broadly rounded throughout ontogeny, umbilical margin narrowly rounded in the adult stage. Weak constrictions with concavo-convex course. Suture line with lanceolate, weakly pouched external lobe and lanceolate adventive lobe. Table 81. Conch measurements, ratios and rates of Zadelsdorfia zana sp. nov. from Mfis (Anti-Atlas), from Bockwinkel & Ebbighausen (2006) .

specimen	dm	ww	wh	uw	ah	ww/dm	ww/wh	uw/dm	WER	IZR
MB.C.3832.3	19.65	12.53	8.79	5.16	6.19	0.64	1.43	0.26	–	0.30
MB.C.3832.2	17.88	11.63	8.16	4.85	6.09	0.65	1.43	0.27	–	0.25
MB.C.3832.8	11.31	7.32	4.74	4.02	2.85	0.65	1.54	0.35	1.79	0.40
MB.C.3832.5	10.62	7.63	3.85	4.11	2.45	0.72	1.98	0.39	1.69	0.36
MB.C.3832.1	10.28	7.36	4.40	3.31	3.02	0.72	1.67	0.32	–	0.31
MB.C.3832.4	9.01	5.86	3.08	3.93	2.04	0.65	1.90	0.44	1.67	0.34

Table 82. Conch ontogeny of Zadelsdorfia zana sp. nov. from Mfis (Anti-Atlas)

dm	conch shape	whorl cross section shape	whorl expansion
3 mm	discoidal; very evolute	strongly depressed; moderately embracing	very low
(ww/dm ~0.45; uw/dm ~0.60)	(ww/wh ~2.20; IZR ~0.20)	(WER ~1.45)
8 mm	thickly discoidal; evolute	moderately depressed; strongly embracing	low
(ww/dm ~0.55; uw/dm ~0.50)	(ww/wh ~1.90; IZR = 0.35)	(WER ~1.55)
15 mm	thinly pachyconic; subevolute	weakly depressed; moderately embracing	low
(ww/dm ~0.65; uw/dm ~0.35)	(ww/wh ~1.45; IZR ~0.25)	(WER ~1.65)

Etymology Acronym for a Zadelsdorfia species from North Africa. Material examined Holotype MOROCCO • Anti-Atlas , Mfis near Taouz , bed 7; Becker Coll.; illustrated byBockwinkel & Ebbighausen (2006: text-fig. 27g –h); MB.C.3832.2. Paratypes MOROCCO • 7 specimens ; Anti-Atlas , Mfis near Taouz , bed 7; Bockwinkel & Ebbighausen Coll.; MB.C.3832.1, MB.C.3832.3 –8 . Description The species newly described here has been worked on in detail by Bockwinkel & Ebbighausen (2006) , so reference can be made here to that description. Remarks Zadelsdorfia zana sp. nov. resembles Z. crassa , but the ontogenetic transition from the initial serpenticonic stage to the more involute subadult stage occurs at a smaller diameter of the conch (uw/ dm ~0.25 at 20 mm dm) compared to Z. crassa (uw/dm = 0.35–0.45 at 20 mm dm). In addition, G. zana has constrictions, which are straight on the flank, whereas in Z. crassa they are directed backwards.