SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10732de2ea0670a08b00951ac384d22748f923227a6e44d275f9b7546bb31ed5' 
  AND token = '8NxJbOjFqoioX/BCriuZukBaSNrNZCxDWgeCBT41U5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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