SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f3aa47c14c23024c0bea2c4043c88bca10f28ed289b6f50f43fa7a26acf96d13' 
  AND token = 'CRQluBEajvdMaKHutV5o3oltvhRnyM2ZOXYsLskY0MI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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