SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1c7edf1339a64fa33848eb2c60389dffc061201d28f0a680b693edf71daeb1e8' 
  AND token = 'Z5tGmLj3pzAvAgStcY5ZCSlqjXPG/6BsG9ofUEtYtKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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