SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82ceb047cf7c785c4aab4a746ec504a98f9fa692d7544766e8b2caf0d190f471' 
  AND token = 'FcwbeI1Ay9eYQnLgnkIGCHbAdkrLDxHWWFnVhz495wI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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