SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04430aac463bf687b98826a1765373aeca9a4864e799b41903f7916fa9f76a77' 
  AND token = 'sZcHUlXj27Gxo5ZaPZRHBNjY97BQtEiGwNMSb88N+WQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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