SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95ad65390c5afb1a75f5737b048b17b0f0476aa9ae3719051d190fa987158ca7' 
  AND token = 'S42doaK2Ze/1x+8NfVrSHwpNHj8vxWeRYkMv+inycR4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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