SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b581444b956fea0da92d5a7a8ae0b8e0375e77c0a01d9c534fbb52652fd3df1b' 
  AND token = 'lDxY2cxCt1/xdXkPq0HThiChRU/7PzRtJ06rRWQNLoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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