SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '867e16fa6314d03e2107c6c08d6fd4ae6481063d859f11fa6602935487458691' 
  AND token = 'dNlh/Ngy94QNqL9w6i9hvmZI8yJpiQ/w2VI7COWAjs4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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