SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b065b6a509b1b83139a135dc5d0c4a0bff2745a261684733241ecb670593450d' 
  AND token = 'AkvpyTEHWbKlvMb7afXBaRLeMz7OtTv7IpC248ZVB88=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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