SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '618fd20bc8b8d17980b2ff65d0e4e97c82cd8a6897d130405916a0ed975da14d' 
  AND token = 'SzgjPqhcWY/HTcwvYyfXKFiTEB+zgAbXii4o1bhn7/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

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