SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc08d7656097f70179f5c6e45bd5504bb3730050d1a5650900ab7e005744bf9d' 
  AND token = 'V45Dnyq6dQ4dsDiSvWzVq9YIR+t1KtTws2F8Ffc9nQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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