SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e84a5de1535767c9cc4b29897a34e06947c38e33ac6cd53a5d5d9510a640e68f' 
  AND token = 'ZPu47kDYuzh0pWdMM62c4C7n4Mtb68+aeHm7B1QtStk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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