SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e2d245a50bca91edd178dfd9677b096569b3f963e7c8ba5a3f2d6a10b6c5072' 
  AND token = 'f64gy/uryUwf8pxZXo9vynXUsyGzZM17kuJNCTSj4xQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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