SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2f61935c371ca83548144d72637f2260babed167af9e8ddbc796c4e5a2c76d95' 
  AND token = '8vwKWflrqzFRfdbyKknkPCDu9fVdpV1MJM8T0KSQxgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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