NANNASTACIDAE Bate, 1866

Artüz, M. Levent & Sakinç, Mehmet, 2020, Marmacuma samimei gen. et sp. nov., (Peracarida; Cumacea; Nannastacidae) from Tarantian (Upper Pleistocene) sediments from the Sea of Marmara, Turkey, Zootaxa 4718 (1), pp. 134-144 : 136-138

Family NANNASTACIDAE Bate, 1866

Marmacuma Artüz & Sakınç, gen nov.

LSID. urn:lsid:zoobank.org:act:D96F213B-61E0-493E-B4CA-213230F8604E

( Figure 2 )

Type species: Marmacuma samimei sp. nov., by monotypy.

Diagnosis: Based on a fossil carapace with characteristics of the family Nannastacidae Bate, 1866 , which differs by tubercles, spines and continuously strong serration on anterolateral, lateral, and posterolateral margins of carapace from the other genera of the family.

Description. The material studied consists of twenty-one specimens collected in a period of two years from five localities ( Figure 1 ) in the Upper Pleistocene sediments in the Sea of Marmara. Most of the specimens represent parts of the carapace, except for one nearly complete carapace. In all specimens no ventral structures are present nor are there any indications of the pleon and pleopods. This is not surprising when one considers that generally modern cumaceans have abdomens that are less calcified than the cephalothorax.

Carapace with pronounced anterolateral processes, with numerous blunt or acute tubercles and spines. Anterolateral, lateral, and posterolateral margins of carapace are strongly serrated.

Etymology. The generic name refers to the location of the sediments from which the specimens were collected, coupled with the generic name Cumacea .

Species. Type species only.

Geographic and geologic distribution.

Specimens referred to this taxon were recorded as been collected from five localities.

The holotype, LA60-001.00, and paratypes, LA60-001.01and LA60-001.02, were collected at locality 40°45.167’N / 027°32.850’E (Station A-2), off Uçmakdere, in the sediment core sample from western deep basin (Tekirdağ Basin), at the depth of 1100 m, on August 2009, in the Sea of Marmara.

Paratypes, AK14-009.00 and DG20-005.00, were collected at locality 40°43.300’N / 029°21.233’E (Station 1), in the sediment core sample from the entrance of the İzmit Bay, at the depth of 90 m, on August 2008 in the Sea of Marmara .

Paratypes, AK21-006.00; AK26-006.00 and AK26-006.01, were collected at locality 40°44.000’ N / 028°00.000’E (Station 2), in the sediment core sample from north off the Kapıdağ Peninsula, at the south part of the Tekirdağ Basin, at the depth of 1042 m, on August 2008, in the Sea of Marmara .

Paratypes, LA14-002.00; LA14-002.01; LA14-002.02; LA16-003.00; LA18-004.00; LA18-004.01; LA18- 004.02; LA20-004.00; LA20-004.01and LA20-004.02, were collected at locality 40°46.767’N / 027°26.983’E (Station 6), in the sediment core sample from off Tekirdağ, (western deep basin), at the depth of 1100 m, on August 2008, in the Sea of Marmara .

Paratype, LA44-001.00, was collected at locality 40°33.017’N / 027°15.367’E ( Station 7), in the sediment core sample from the connection of Dardanelles with the Sea of Marmara, (on the shelf between Karabiga and Şarköy), at the depth of 92 m, on August 2008, in the Sea of Marmara .

Geologic range. Based on the new fossils (present study), the Geologic Range of Nannastacidae is Upper Pleistocene to present.

Figures

FIGURE 1. Map of the Sea of Marmara from which the sampling locations of the sediment cores of Marmacuma samimei gen. et sp. nov., were collected.

FIGURE 2. Cephalothorax of Marmacuma samimei gen. et sp. nov. (A) Holotype (LA60-001.00) carapax from dorsal; (B) Holotype (LA60-001.00) cephalothorax in ventro-lateral view; (C) Paratype (LA16-003.00) cephalothorax lateral right side; (D) Paratype (AK26-006.01) cephalothorax front region from inside lateral; (E) Paratype (AK29-003.00) cephalothorax left side lateral; (F) Paratype (AK29-003.00) inside of cephalothorax left side lateral (scale bars 200 μm).