SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdf3af47ef12c367a9e6e111efebca48718bd2c0945663aa7fb2871d3ca17b20' 
  AND token = '/NgPYpNzM1IyPm3FWTBENWQsigD1Z6+JS3pl1cnSnXA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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