SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6b34d6357208a2dd1b36e3f71976553492eea41c7bb715b65c386baa8addf2bf' 
  AND token = 'QEUBeKYyxoktzMVUqKU17eoX6jiTfojq5y1vDajDDME=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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