SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ffd204116a8730eec360574a0b8af64cb286a0416646424144427d839f270b5' 
  AND token = 'zz0QLjqUzFCNR59nVhyFnbuyu8wm7Cg9KSyHe7cIaYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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