SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bcaafcf53240ffa3d20ce1096f158f4fed80c5eddb2252b1b40cabfafb29c260' 
  AND token = '9Nr/FgmLOYVT9JmVK1RsYZhLr99J7vSA+8jxSTGK7ck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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