SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c7e62b4db8042bffa6d1c0ae405a1fd1e0f50d57f6fa5d6af5bb0df5906635e' 
  AND token = '7muFO4KjdaStNcde52Pjmw6wvg59+EO5VgQovv62BQw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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