SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7fcb5379cc3499a0f7f94d29f7a1d3f5ec70dffad5d64c046876d2c261e0315b' 
  AND token = 'JJTMFOCbL2T6AszgBazBSJLRPuZYyXr75foBs/n9nS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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