SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd2c9238b02acf4f259dec65d6f685cfc027a8f53def92e5057b08fe61e858dbf' 
  AND token = 'e0L5luD5Ro35MOKVQgCLyYmNw+PLCJUqIy4ZBVvmPvY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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