SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af2d898805daf7de7b37c5036b47fdc007516db79f1cb3d905f3d78332226c24' 
  AND token = 'ngg98TkYu6Bz2HIKJ/eiWlWSsy71P1jsmj6VSzIH/ZA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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