SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de1a09b47ec35a91cc3c33f49c131e199187cd8415070edea60d98f54910a195' 
  AND token = 'OiaB7T09VZma2e/7uC80DpRj26Z8B1xZuMqV+jh4YXI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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