SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82e781f03d45ff1ad25c2106c9d6ad6d0d5ffdf8b361aedbcb7959caa3c1eabf' 
  AND token = 'S+9RvC5ZZf74rwg7UTS65+uWAAKlTHjf2IGaPhOUZNA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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