SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b1f96e93b06fedd0b20d56fe54b8f560b46923f74647d6dd20673340f155cc7' 
  AND token = 'YG9VjaJISHBsQJ/U6IjWXLVvX+UVLEMa2502l8jgVec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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