SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc9bb1cdff18812f7e4d7229af90b934466f097ac361f75163786bbd090b2926' 
  AND token = 'sBPiRVqTEeIp/J5+47cft+WM+pxz4wTV6HxPLRSZ15s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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