SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7cc9ecd04b9424dc314885ee1563bbf8e889a3e3492711b47b61ae6f953798a1' 
  AND token = 'Fm35plTlTR+vL9hdHp7ej7W3TnsOI6iUTuGRCkeaC9o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}