SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a7ad62e6e86d5320e49d99ae8a4bf848c1de7bebcbcde8509b4aa6cd8781b544' 
  AND token = 'YwQRgVbE49phqd5C7stin4WjYCdJcLRrfpJd2meDxyM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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