SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '922c77f4834602451c637d48b8c1f3e794b830982342e1cf1cc240603ae35e7f' 
  AND token = 'rumUa27z23yheucUHKHJjiEmc06vzLKsTKXqmFM2vkk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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