SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9ee96a6b45304c980e22c3adaa1df3acc0954196be53fd85f1de60f36747a0f2' 
  AND token = 'SUgw9YND7WaIhyDHjVGZjM+BH7Oofc/KzPGpHqmI1Ns=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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