SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '539f0a757baa5eae1ede2cb44857ffdb8a3edaf98b1071bd7c1c5b05e13c9cf1' 
  AND token = 'I8zu3JL6x32QzSseC2BSpp8HgejU0WloEE01QnHSmvc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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