SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84445bef4c117ccacf027c29b228d955a20cad1e7ccc907d4ba65a74b4566aad' 
  AND token = 'T6B7+OFC4zW+dEiuQpVAZ28yknWRzc86CBiSffFNLUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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