SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06732b017196f17441779489a2d071105aa1f311ebf1977f55299c33cc4a7b6d' 
  AND token = 'spJfoYRq/UirGmneD5mZJXE4bLrO7gqmy4mnZguMvZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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