SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '722212d733100e95e683a0541a3e8debec190cddd2f9882750b5a4fc9650669d' 
  AND token = 'u2kgZMAOe7yYx9OTQZ6ZzPrf3DPgGMysZcrdVsEbEQs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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