SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e971e81f2a75a01d5821e67d463cccc4f43073b4cb55831fc85e6198a20dfb1' 
  AND token = 'aQvAYWqBwZcgMS5gMMQoTnX6LTFNbHs+gShqf03/ZwQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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