SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a31c9ed3b9952a4f295f361e7ce20ff62c871103c4562d692d8da11d8564a9b6' 
  AND token = 'rk8CFSIhlh2UgsR5eCKJbACvavjXWqLnN2wovf5m7eY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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