SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '170be294fb53160a07580c5521c14de3f09c0c59b5f222d9c137746995d65417' 
  AND token = 'sCg+4iW1NcOGQmrg/6HPEoW1y6WpOa4fPATUiBt8iOQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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