SELECT 
  1 
FROM 
  csscart_lock_keys 
WHERE 
  key_id = 'c8d0a530d4f7be9c64aae7cb33dce37fce1c9e06eddf0239b788678c9dbd3876' 
  AND token = 'rAjMzfZQq+mTNKHp55UfBVIYjKxYW1nTg/NGN/UzMgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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