SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd9e7d4c67b43ae9ee9fba38a4e958b22fbd6512164757476f4df1e2e20a0cc2' 
  AND token = 'xGJSwRVIX0+PUl5MblgF/nGfs/yOoHX7ZYFMmTZ4KnI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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