SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a2b3b4203e3eee4abadeee0c1528c014257b136d48425115c9f8336c71a484c4' 
  AND token = 'GuWndd6oQY4Rp5SljxRA5UcZNuLrrJdQ4WWYCwMMFKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}