SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '499618106566f0a263a25c997c64208e2a9f5815efe0ba378da31d2244e51ab0' 
  AND token = 'tz7R0QS5OcethagMed4gK3TuwLEcpewKcTenB9/7u/Y=' 
  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"
    }
  }
}