SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf94b4252cb93d39f71616a320af65708b82dba3fc4d679c4c9f4a881f4056ff' 
  AND token = 'oDEkWubsrVz/ntYBAxhsrOZwHwmRMiONbs5zN4zFitY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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