SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '6078e641e531399266c898dc8a775ec6d8b179ef0be8a2dc07d9034807b74bed' 
  AND token = 'u0iG/fl/yzaNKMfMFkdnJJ4bOGRo3ghFqBzA5rmIHoA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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