SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cae9c6536ea45dfbb172f497fb6a3dff7794b4e5fd5898b1c2788a9a8048c32' 
  AND token = 'kHU4hsrTxJfOEpK4DFpE9ZghGHKMj8Hv8nF6d8n4xXs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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