SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b97455073ae6476fa0678febd2763620124a3d5e45a243d8adc1779fff9a83c2' 
  AND token = 'u6b5gPpd5z1OXj8Jk/s51hj7Uw6R0N46Bx7yDYP6jTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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