SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b5e352a91b23dd7de8d6108f083d9dff7f8d5a209d184b3af8a85077df6ce1b' 
  AND token = 'rzlG1xONYZsaPph8YpSdyD1WbhLGHlhYRPJNrBQ9FiY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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