SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '163a9159bf26f41f75a1aa0e9fffe21130fd7eca58848a30e1306ff8b8b2d665' 
  AND token = 'PrJApZFbMYW6Ni7+hqA9FjcZW4/vklFj1fhuxHo/qYw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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