SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '63f663c60cef21863419a7242c68ee1bdfd88afb1592850187642fbaed51948b' 
  AND token = '/TRMCA4fVr0Oexp7NFjRvJ0srn3Vzd5krSVL83wuOw0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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