SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '911a9c5d0669173ddf9436740aba3eb75729762265383d2e45297765887fe786' 
  AND token = 'pwDsdgNcSzMJFLhMYyI+uDEndcay4hpYB3/YY+J/IaY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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