SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e483e4766e3e671abe25ae148d1885749eb7d8853878c9fab28b142c41b2863' 
  AND token = 'hds+ZXhu3SGVpPQTqo7xWiB4Rv2rHIQZ2QOJ6tPggiA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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