SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8aabe3bd3f71980886f873593bcb921d6116130b7e78bef419d0929036adfc6' 
  AND token = 'TyfC0VqePcUnsjYTYaOM80rKvSiyMERAmlujjkONNgI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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