SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '621b8bb4bf064e20cda4b130bb7f68e34df04425283ff9f2409a1a67dbacf1fc' 
  AND token = 'BmVngeP35HI5gb4Oe6eHDb0MSJeNC+ObA6SLEDU5A6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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