Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5f4261e6b87afe96b7f85d176bbe3d6d2a851b7c5ddce9afaf254a350abe4d8' 
  AND token = '+tuNU7FnRLSH6vezFkZtmYbWwHg/UQx7DSeNc1KrU8k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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