SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c26fe379e7ad4c874171402d1124a01f7b9604f72539d119536c5f2dc5fe20db' 
  AND token = '3pOS5CKUJU/DEeKUTg/hJ1IPEF3z9UZxHj4v+Q1Er8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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