SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '949b4d56f4b79693a293b1728dbe68cd491dccc62e6c2031670c0be7370ebb1d' 
  AND token = 'XlJzwANZgPCC20N7ktsNRU0pO/TNjjHE0LJJ3JRy5cc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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