SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46d6a3207547344bf75eab50276531301044998ddcf922a09b6189abb6568226' 
  AND token = 'AfnKqUduGS0Ozw2gSp58U3xUICciYgMshd8NE1an10s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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