SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd059835139c037e161e552a91d1f48ca70e3fbde72bb3205eb0168d2ae0cf6a8' 
  AND token = 'vY3gRtLjpDzcUxG6j8qDlV4J9RFTYcIRUguFiO7yQG0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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