SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e5bd5619e28d7db3e5629fd6ffc03591159cd076e77148c00d0feff5ff6a014' 
  AND token = 'bRjK1qFlSfqfBfHTHuX6pPYk956xkaX4rIdQWBzi4ls=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}