SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd76c352b9538f23f84864e5add49817b80d13ee1dbfb98ac6310cfe211d39f77' 
  AND token = 'I5RiymEKOSzS0Ii9m+JweUw18iIPwDFQjU83pbdGPu0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}