SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61bcd064b3e15f79db8e762b13ead33bd69835921405ce5b15358b6327ed7e36' 
  AND token = 'NNWbQgh1IQURvwdPEFl0t1L8pemnsacVowW/qQrcNnI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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