SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4ce89f0c7962112f037ee22a926cba0ded5b029933f17b7a49dab3b1979cc9fe' 
  AND token = 'wwSNV/NUshcKDFLM7lZfO+J38PM9tDI6QASKvwaXcJ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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