SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '373755ac090b727ce84728918797725266e043c8c91e501862dcaa1c7d0d64aa' 
  AND token = '4HKQ51d5JRzjm3CFr3eJCXvBlr2+wP/S6FUfhKH+hcA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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