SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '81652fc6404d0c036d04985d33f53fd444b9cfd275ee502b2dbe50476754a6f7' 
  AND token = 'Y2AtQzI5NBhQ72oTc1vh0Hdsb7iRKoWP2YP4xXSl/yw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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