SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bffeb1fd71bd14c83356c61e62ede8952e2be0169fc12063688b06e0790f86f' 
  AND token = 'PtJYNhe50hz5pk6uJQDstIooKzmWNtRyKvNT/83s8DE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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