Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b838ab16d0d8adbd91a724f7d7ffae2ad87d053dfe81d9beaa2bf6f6ee1bca2' 
  AND token = '7jk/IxqB4gQjbTy+sxvjp4fhCx/nVxh53Pa1Zcjod4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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