SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45213992d631489d6642fbcff219581edd5365887cf1c044151a1df52664f2c3' 
  AND token = 'ShmZuaGLn7D1KtK9lqeSAjIac048Fh5dQbrUwh7+5dE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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