SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0caf317be7648e3b98f4cab1311a34daa5fb6a0f752917f54beaea9d20de61e5' 
  AND token = '/YUQUwlkD6tKwWudz5OVagU/XXhSBWiugxMb6wLxF3Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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