SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a5be053aaa2a6fa38010fe456be3e88479f25277068be4eb8d98e9e96c5fb40b' 
  AND token = 'fKVpF3ZyQlGBVgrjw+BJmlq2Q0XgrQOYrraU72YsT0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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