SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69e7e198d00af9385ba9a13e4c39047dfd10af6078766c8be30e59c7df7ba1d4' 
  AND token = 'XqTPVdFUkw2o8y7BPXIpBecgFzzYwZkS19FbzatD6eg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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