Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b996c1c780304f7855798a80cab1ae6c5918fee3588ddbca3a34c3466fa37d93' 
  AND token = 'yLXwl0kNZpCUADqbRv3stHVchOciw36Xf0Z7dGuAWQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}