SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41fa484f564706a68c774f0906bb3511192ede71fffdf8701df60049d9510763' 
  AND token = 'X35Z+lWSXX/1JhoulUZBOlKCmmRR0vAYUFURzgPq0/8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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