SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1809088eb1a23a78cea3e9af820fb7c88825e52b8a3af209497cc009c9836a6' 
  AND token = 'CzGr6GDPGHC+miSIp0x3wt5VxChAnoyoQivHhNmKGcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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