SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfab3352bccdc69fc2b6df9f0c43d92359351ec033b74cfdede596aaab7c03ec' 
  AND token = 'Bxl4SuYrpSMWwNZCiiwLusAVfv5GTkwub1YmbXDk5Cg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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