SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f80c8f11e32f4e658c5a577c0e815bff5b9beb198c014396cf6b86982c1b7e40' 
  AND token = 'nm5wz20qfkHgvQ3TZOnXEhNSYV5JPm8lYmFr3FzVMmM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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