SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eada55ab8269f81592dbd24279b98dace43cc7c4a4e27fded476403f10606687' 
  AND token = 'T5BEU7lHpwa0bR7rcVIXUxLXOX7U0knRrU5EAk/a0q8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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