SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5ea65997660fb75607ac127c72963fa7d839266a9807d3d5e0cfd9c142fd4d86' 
  AND token = 'KcKSJT6bMBXm5f/Hhft+/hEMPjFTtpgA6wBgJnNiQzI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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