SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec0c1a539c332fc50e263760d2925bf2d8669115a4084a5533a5b1b80e257106' 
  AND token = '2Uuhb/sHfuaGQKTwJzxOffMHurwFZpEJ8ZZwZJzYuVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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