SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '866f0b54ff2e2b501b763b943bace21b30cefad5601d03e3df35dbc0ae8fc357' 
  AND token = 'Tezs5Aj0xapn+PTindgaQQaqJnyt31Yecrt2LXwmwcw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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