SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e8a455e7708d8f2be6eece74e3e5071d4c13ee1ac1fa4fc87da7166ad2c7388' 
  AND token = 'jSimpljFPZIvAzhcxqEHtQEMUnWFvHgxDaKPig8glFk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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