SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43be7465276a2148007dd5359821b183e5def7f7a9739b74fa9a7b9dd7e93ca6' 
  AND token = 'pWWerRLIsv5KUV8MhIe3HUYBBhl+YP/P9COXP42rp3w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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