SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d60cc426b244a12ec74676070825fe2dddace49685af86b7e8bc96b0cf701e7' 
  AND token = 'Whhz7VYkYtLejIhtIr0bW4bfONR1YOPQgJeKAS/scgo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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