SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e359f3f128925f206b574b8fd9cd566406d302af137473d63f5f781593643a57' 
  AND token = 'JUld8/XFc8XN3+2f4loZfbbnLXtOfPNqx1ulgWXByTk=' 
  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"
    }
  }
}