SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '24028f599dde89a8afefe7f4c0f4dc1c81533afbeb9e36f40a6089be630969d5' 
  AND token = '2a72fiTwV5lww1Gqd/mCCTRKbTo3huQgyXdMUafeWVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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