SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9245451d29e003ffb8cb47c5e82fd1ca1afb5d34293261388eea03a0cb53ae93' 
  AND token = 'B12EIiwhZvenPNaSMaGD3zWoPdFrPlXBwIVAR8ASbuc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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