SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7762bd9a4df50c0479f8acc9989ba01db718b7e93ba70160f5336cdc3acf9943' 
  AND token = 'jzJuC0LiAjI1XISUIhlV21r0pAlYENo5WHEB4kIRrAw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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