SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34927c3e9c7c8d62e1f19b9084fb7233068559214d591aee0f6b28fc68132a4a' 
  AND token = 'XjBfG0x+jgpzPf/sFoWWaaEz2iq0vW4zk1vuLFIgRxU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}