Metaclimacograptus asejradi Legrand, 1993

Metaclimacograptus asejradi Legrand, 1993

Figures 8B View FIGURE 8 ; 9H, I View FIGURE 9

1989 Paraclimacograptus sp. ; Rodríguez Núñez et al., pl. 2, fig. 5.

1993 Metaclimacograptus (?) asejradi nov.

sp.; Legrand, p. 423, fig. 5e, f.

1998a Metaclimacograptus asejradi, Legrand 1993 ; Štorch, pl. I, fig. 1; text-fig.3, fig. 9.

1998 Metaclimacograptus cf. asejradi Legrand ; Gutiérrez-Marco and Štorch, pp.

87–88, fig. 10e, f.

2003a Metaclimacograptus cf. M. asejradi Legrand, 1993 ; Lenz, Cuerda, and Peralta, p. 1200, figs. 3.7–3.9.

2003b Metaclimacograptus cf. asejradi Legrand, 1993 ; Lenz, Cuerda, and Peralta, figs. 3.1–3.3; 4.6–4.8

2012 Metaclimacograptus cf. asejradi Legrand, 1993 ; Tortello, Uriz, Alfaro, Cingolani, Bidone and Inchausti, p. 293–294, figs. 8.6, 8.7, 9.1.

2015 Metaclimacograptus asejradi Legrand ; Loydell, Frýda, and Gutiérrez-Marco, p.

766, fig. 16AB.

2023 Metaclimacograptus asejradi Legrand, 1993 ; López and Kaufmann, fig. 3C–3D.

Holotype. specimen no. 1815 al, figured by Legrand (1993, fig. 5e); Tioukeline Claystones, north-

west of Ouallene (Asejrad, Algeria); turriculatus s.

l. Biozone (early Telychian)

Material. 23 specimens, mostly complete, both mature and juvenile tubaria, preserved as flattened impressions, rarely in very low relief.

Diagnosis. The tubarium with an asymmetrical proximal end of normalograptid appearance, markedly widening from 0.7–0.9 mm at the first thecal pair to 1.2–1.4 mm at about th 4. Median septum undulating. Thecae are densely spaced, sharply geniculated, with short (0.4–0.5 mm), parallel-sided supragenicular wall and deep and relatively broad apertural excavation perpendicular to the tubarium. Two thecae repeat distance of 1.3–1.4 mm proximally, and up to 1.7 mm distally.

Description. The tubarium is relatively robust. The length commonly varies between 7–8 mm. One exception was a specimen that was 13 mm long. The sicula is almost completely covered, with an aperture width of 0.35 mm. The proximal end is blunt, rounded and slightly asymmetrical. The virgella is 0.3–0.78 mm long, usually preserved. Dorso-ventral width (DVW) varies between 0.7 and 0.9 mm at the level of the 1 st thecal pair and gradually increases through 1.2–1.3 mm at the third thecal pair to the maximum 1.3–1.4 mm attained at the fifth thecal pair. Thecae are sharply geniculated, and their double sigmoidal curvature is rarely visible. Short and slightly convex supragenicular ventral walls are 0.4–0.5 mm long at th 5 and parallel to the tubarium axis. Each of the relatively narrow and deep apertural excavations without apparent hoods occupies approximately one-quarter to one-third of the tubarium width at th 5. The 2TRD varies between 1.3 and 1.4 mm at th 2 and th 5. The 2TRD 10 is about 1.7 mm. The median septum undulates, but details are not visible. The nema is occasionally preserved.

Remarks. In comparison to other species of Metaclimacograptus from the linnaei and lower turriculatus biozones, Metaclimacograptus asejradi is a well-recognizable species even in flattened specimens. It is characterized by its wide tubarium, short ventral supragenicular walls, regularly pronounced undulation of the median septum and slightly but distinctly asymmetric proximal end. Metaclimacograptus undulatus , described by Kurck (1882), is much smaller and narrower, with more closely spaced thecae and a rounded, symmetrical proximal end of the parallel-sided tubarium. The specimens studied here correspond to the description of Štorch (1998a) and Gutiérrez-Marco and Štorch (1998). However, the strongly undulating medium septum is poorly visible in most, flattened specimens.

Several authors recorded M. asejradi from the region of South America (see synonymy). López and Kaufmann (2023) recently described M. asejradi from Argentina from levels assigned to the Stimulograptus sedgwickii Biozone of the Aeronian age. Thus, its stratigraphic range may be longer than has been recorded so far.

Family NORMALOGRAPTIDAE Štorch and Serpagli, 1993, p. 14

Genus CLINOCLIMACOGRAPTUS Bulman and Rickards 1968 , emend. Bulman and Rickards 1968 and Maletz, 2019

Type species. Clinoclimacograptus retroversus Bulman and Rickards 1968 ; by original designation; from the Llandovery of Tommarp, Sweden.