SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a73c4d935cd54bfa25392291133545d0232f378a1c13e930c9c98a489c5327ff' 
  AND token = 'h8bzLopD8c3+X2PIV4XpIpKT9oZKq786B8JCVWuxH6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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