SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ab85ff954736198cf80a851ab3dbf8946789cf15235fbd377820b74b6634518' 
  AND token = 'O2sED0KgqGhmHY8qI7z1VQ9+4k44SQziHT3U01FkMcc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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