SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb4dc549fb9f97e066b6cf84a4f837719578f4367bff1af153950e026abbf20e' 
  AND token = 'Rt8Oosgaoh1TOdv1BwtH/tRsYVG3qXGsRh83fPSo0Sc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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