SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f84b7d712e603bdbbdb049604aab3e22e0ce7e2c6664d887334531f01e7d6d62' 
  AND token = 'byh+B9imPoWxi/astHlTDNsSizz2qjQ1Toalyxgv1oY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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