SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aac8c3c5b2569bd90d1e25feb4bbcb651ae106f3706a217a413606abfdb91ca0' 
  AND token = 'ePMHy0SWQpolD/1oOdh5tqdTlNTofG6ZQMFTxTH4Rgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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