SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59067bca53e747a4261cb1652e5483fae5d7a2fceedf3421e4d812f0d8597246' 
  AND token = 'Osiw3GNRh/tqGShZO3l+jZqtZPUV50fMr6doBeS9F98=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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