SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a105c8acd05b475d833e871599b88da1bf98f8dd468bd9d6defa4579ecc6accc' 
  AND token = 'lStPR0BdeGB4bHuVdBVTEbKsgXqkDDCU85zhVEPYrcA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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