SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c824e97b29458953e92d07de6c84790fd25e9febc72379ec4cdb0577a9078bd' 
  AND token = 'XmCwDrmgohWa6TOZLiN6zi/XpxWhyLQDHbwDKf7ZT44=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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