SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bcbc1393df9f9e1d5b838bad4da4b06be55ed9ac3b376747c0a2eddcf624bc7a' 
  AND token = 'FDZMKri8x8DQzz76gyij7Oa9wNgQQyCAWnmMaGYtztw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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