SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8c88a44b504eec0c975c19eb94eb97a5a581ca68d24a8c152f3906264231a2d' 
  AND token = 'WEAHcOLoZV9nv0PrTrLRmWZRIizNUJM0kl+KkMvCIE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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