SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd57adb33017b11750e07393dc518b5db9c826d1d72a61e22ba54009c92997e6b' 
  AND token = 'X8HAC6m6B8sVvG4BB8kpzeMjpRfkqhgFuhOCIwZKPKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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