SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ae481122f5fda4216433d03d27d1e3b045cc4e30e9b157aec62c562d2c831da' 
  AND token = 'nNPrZ98P31BXWpjpkOeF3Zt3Q3mJeo3Fnsy0f79jc50=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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