SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '142ad2237208a8a565aaf7cfb75ec17563eb4dcf76fc91688375c72214d160b3' 
  AND token = 'UcwAVMYBC6Y8zijTyRNRbh0F7kdEEqrNZiSnv3SeF8Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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