Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a99e886f6e95a8d45cdafba3de4df06d879731285f84ca60162983247b95a207' 
  AND token = 'rCz6EtRvYhKygoqeahYIpXKmif+A7SPmzEtP784KZXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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