SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fca717ddfba6c5171cc94d7fc92ae38a1b8cad33b6596caf7a3f092088591967' 
  AND token = 'U3W70WMYDNerfPii4iiVdAPXGrEOVoZqCbSP41/ZiSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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