SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a5b97daaa70233b560e0ce7600fce0d578752e08fc8e8778a3a606ddabbf62d' 
  AND token = 'zPhvalwbDuZp6UJmugkhpMDX4FLaNHc6cQgUTpcfY8A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}