Cucumericrus Temporal range:
| |
---|---|
![]() | |
Trunk appengae of Cucumericrus decoratus | |
Scientific classification
![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Stem group: | Arthropoda |
Genus: | †
Cucumericrus Hou, Bergstrom & Ahlberg, 1995 |
Type species | |
Cucumericrus decoratus Hou, Bergstrom & Ahlberg, 1995
|
Cucumericrus ("cucumber-leg") is an extinct genus of stem- arthropod. The type and only species is Cucumericrus decoratus, with fossils discovered from the Maotianshan Shales of Yunnan, China. [1]
Cucumericrus known from a few poorly preserved specimens. [1] [2] Only fragments of trunk cuticle and corresponded appendages had been revealed, while important taxonomic features such as head structures are unknown. [2] [3] The trunk cuticle possess irregular wrinkles [1] and may had been soft in life. [4] Each of the trunk appendage compose of a dorsal flap-like element and a ventral stubby leg with unknown distal region, [1] structurally comparable to the trunk appendages of gill lobopodians (dorsal flaps and ventral lobopods) and euarthropod biramous appendages (flap-like exopod and limb-like endopod). [3] [5] Anterior margin of the flap lined with ray-like structures, similar to the body flaps of some radiodonts. The legs have been interpreted as somewhere between annulated lobopod legs and segmented arthropod legs. [4] [5]
Cucumericrus was originally described as a radiodont alongside Parapeytoia, a genus with somewhat similar trunk appendages, but later revealed to be a megacheiran [6] [7] [8] [9] being misinterpreted as a leg-bearing radiodont at that time. [1] The radiodont affinity of Cucumericrus remain questionable, since the presence of legs is unknown from any other radiodonts and no other radiodont key features (e.g. frontal appendages; oral cone; head sclerites) had been discovered. Only a few phylogenetic analysis including Cucumericrus, either resolving it in a polytomy between euarthropods and other radiodonts (alongside Caryosyntrips) [10] [11] or closer to euarthropods (as a basal deuteropod) than radiodonts. [12]
Cucumericrus Temporal range:
| |
---|---|
![]() | |
Trunk appengae of Cucumericrus decoratus | |
Scientific classification
![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Stem group: | Arthropoda |
Genus: | †
Cucumericrus Hou, Bergstrom & Ahlberg, 1995 |
Type species | |
Cucumericrus decoratus Hou, Bergstrom & Ahlberg, 1995
|
Cucumericrus ("cucumber-leg") is an extinct genus of stem- arthropod. The type and only species is Cucumericrus decoratus, with fossils discovered from the Maotianshan Shales of Yunnan, China. [1]
Cucumericrus known from a few poorly preserved specimens. [1] [2] Only fragments of trunk cuticle and corresponded appendages had been revealed, while important taxonomic features such as head structures are unknown. [2] [3] The trunk cuticle possess irregular wrinkles [1] and may had been soft in life. [4] Each of the trunk appendage compose of a dorsal flap-like element and a ventral stubby leg with unknown distal region, [1] structurally comparable to the trunk appendages of gill lobopodians (dorsal flaps and ventral lobopods) and euarthropod biramous appendages (flap-like exopod and limb-like endopod). [3] [5] Anterior margin of the flap lined with ray-like structures, similar to the body flaps of some radiodonts. The legs have been interpreted as somewhere between annulated lobopod legs and segmented arthropod legs. [4] [5]
Cucumericrus was originally described as a radiodont alongside Parapeytoia, a genus with somewhat similar trunk appendages, but later revealed to be a megacheiran [6] [7] [8] [9] being misinterpreted as a leg-bearing radiodont at that time. [1] The radiodont affinity of Cucumericrus remain questionable, since the presence of legs is unknown from any other radiodonts and no other radiodont key features (e.g. frontal appendages; oral cone; head sclerites) had been discovered. Only a few phylogenetic analysis including Cucumericrus, either resolving it in a polytomy between euarthropods and other radiodonts (alongside Caryosyntrips) [10] [11] or closer to euarthropods (as a basal deuteropod) than radiodonts. [12]