SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e179a771b5f6f39131fde35124258b4338890e77327004191574635c916e5add' 
  AND token = 'vZcQDOYm4e10zjpY05ku/LXe1tSW8zvTHCUlkdEyx7g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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