SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'db83eb239a9bd52f01534a3da98e5e8e6667cda09c2ef6bfe7bd99166607e95e' 
  AND token = 'vvwbph4cmje/ZHjkNAM8TkI1KvEqPYRn49TElVTP/Pk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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