SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '84c991cfe1062dc66a07a72c23e12efb478ae84fd95355c31744dcf043e11a26' 
  AND token = 'mKyADPcRRzf2+tYKfH6KCUCoZiUsY0v8jpVK0JwIZ9A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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