SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e89924fd3c855912b053cf6fafc09da6c6bcdb668d29f4eb969b7d20f30e1f6' 
  AND token = 'QW+pDawrNZBmv+OA+d24Ck1VpCHc0TD/3xy/Ym6ZNW4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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