SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd604ba684065c0f1588f9d6c3b3b6d4b178c5be57ac5b89958e4eef131adb58b' 
  AND token = 'kQ/cevtatqzlAv8BNJYP1BGzLgVGgqvgURPISWhCQa4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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