SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2048cd7bcd72319a5f8662bd56d2855545363dec6e1251e75ac40117a9c6c77' 
  AND token = 'LiCaOwnMkwpibdcHmnqWNIOFTBrIK1J6zdlts8RFq4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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