SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbd5305e88354458573f4ae31b3f760e28bf3f3ef874e9fa16862790563e235f' 
  AND token = 'E62bj6SWeKrkzeYea71PoVPgSUcTgtUg0I6mMQZTwBQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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