SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e96eeb6f3beee08a85998d2b5a41f96310ac5517d29b6bfa95c73c30dc1a70fb' 
  AND token = '7nDBfN59oDSX8Da0tW2jxXYUmvayLCKoPlK+j6rxFRQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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