SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee7bc19bf557517356967d405990e26e57453d97c018a92bcc77dc8dba780f82' 
  AND token = 'TRfKY2ryD+ZVSc6U8gUD08AIzlmeLlARAmbbjPfGUK8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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