SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '810308679336d986c2af1dc933fc4e7792f1346a3b04b8b379966154d82617a0' 
  AND token = 'JNRwWe+94dO5h+n59gz2DMTEzLnUTyneBJDupwFPGNk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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