SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87788bb54d7802f1febc0232de503590fc6bda6117cf0499287eed1a604e543c' 
  AND token = 'keY0M8H/LgZlZrAdo9ipTfmyytXM26uFTX26gAaw5SY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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