SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06a2cebfa57e30136ed4a5e6190ab41625d290377350dfa3de5050fd92c910f8' 
  AND token = 'vv3Pkq0qUWbZKP6BSpZQ54+mQKgbypG9Rtj9CG3AcJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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