SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb720006c4606242ad827970b915bb177b291a415c9956639e4802297e78095a' 
  AND token = 'IGZuwE8BOlcxiyNCe91LfMmOQJpoO+h6mKkw4prQYQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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