SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4aa81e7641aaf1377cdfc4e23551bf1d9c38474add6531429e95fd1ef15219f4' 
  AND token = 'WGyyB8E/RTmeIh+y1sS06Incs/Z8OXBxMgo7jijFLZE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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