SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b41edd6dc59e7cb3754d2fdbd446fe61bea5cbd9d1c148859800b4a525da7f3' 
  AND token = 'WkG4u6PWkBEq+dLf/8L+VO0Ebj18O/3YaeH/DX7oIZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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