SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eef6a701984dad4a20a736b21e170daaac17c0fd6002e0d9d3e02117ec4ec517' 
  AND token = 'nF5OKsho2unZxXYBaDGOMPY05nrWhEOxnFZxOc+XYCw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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