SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff924b35c0ce02375b1aae1c8b70c119234be2596e5dcead3d9590aa5ff19bfe' 
  AND token = 'iCBg6Nk8RSlC7fxyNQn/hhPOldKCaiKxK3vtbWsuxmE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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