SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '433d4a5ee47c27fe52600892e1104d2470563fb10912579de58ac5e7a1057be0' 
  AND token = 'Vens/VfmDkOnSbazIJ3SpDR2vvVVEKpHVRIYvn/i3AE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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