Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4e8bb7eb40b555d0cecc483455b3f227c297511acaec24f3c92107be1f0a8e1' 
  AND token = '+D1HDa6sS3ZMQg8f0F/PJ3uU+NoWupV2xsG6Ps2K0ho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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