SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e356d0db5d0617c3d4515a9798cc0768ecf32b706745494933f2752b09655f98' 
  AND token = 'C9X1CM95KJVIFluQFknSjXdxEw7OBa02JbFUOS83aMo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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