SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '211a530c5a310ba4bdbe2da7d4d069edcfa7086e458bc751afcaa5b2d47921bc' 
  AND token = '3sONlxjVuq19Vc6X9fptK3OSnO+B9XrU88VRYmN5yDc=' 
  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"
    }
  }
}