SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f09d20d802b1dacd33550626bf17b29e9b52880384c1b10b9fa60f8527ad2aca' 
  AND token = 'Mm3n/6ds3v9+TwvDGFtYyeYT711qIoPKIg7lw8lQX8k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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