SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '052a9d129d1537735e0476ca267d99f78fe24669582b465cc3eb9588263404b0' 
  AND token = 'rlOe9YagnV8n/tk/0ZvGtlsneLqHWmWQ0R2qHboT+Ic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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