SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bbd46c2d04307f44f83241abb4b073a45e538e65ef5683d37006d381940ffadf' 
  AND token = '2itezPP8Emw5nDdHFlGY14PMRL4N9N8YXwbPEG2z7WI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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