SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8c0c3f1b3ff051c6976a95ebef20741979ab705a57ca99a0014777437d7414c3' 
  AND token = 'mBNWAEJKGkyPsxvAqSuB4hgnd+SATIYJ1M02Kx/RSI4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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