SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa29f739c980e014b865614f22fcc15bd5a30b3b37b40f5d35207a827adaf5de' 
  AND token = 'JD8VcDnZQw9QiGsrTuWYTFhKEh4B7Kq4ySFcddCqAKw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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