SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '852b6d43cb1b9ba11b9cdfe4308b7ce5f237a8c51f7e100ade964fe544d12dc7' 
  AND token = 'gQbTw8/KhYCbe5JJHWrww8cR5ejfHVzJj5w9JqDAnt8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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