SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd470c3594585542561ab7fa7fb1a345c6fd8d24599f1ef1d173709a1cb611d72' 
  AND token = 'ZatjMyf/9N0kXiurW6IekX2Amh66WPhm5zGasfzXKYI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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