Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6adbaa3a768253945091b0311da021e6dd4f040e73a7fe22081af1c907928f77' 
  AND token = 'C+sw/ldmSdRckt4MemXKqFuJzrwyf562tUcqajOoxIk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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