SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab5cc72adec1ab9cae3b9597d41e7039c965dfb6f7c8a74a95c5fda9d324da64' 
  AND token = 'Y9MSznlmw6fsUISpQGPJoba64OZmKH+nhVg8Y19wt+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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