SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5ea5cbfa6c8362c2bc091ae6f94cccc678caae6ec96c58de466ad2094131210' 
  AND token = 'foy7nTrOasmHoNi5XVYYTHIhzEfNrepTLLZ3PNnOi9k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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