SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d30540d1258663c0428d7bacff87445a2a151f196d414990c04456cee494947' 
  AND token = 'n6fD0gsNCOyVIrQMJISku86NG/05xy6yU3lNGB2oV2s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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