SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5442a85ce759426fa0c7488d311664f0031e92e3eb49713f98911ef9a84d1a55' 
  AND token = 'd+miNahO06voMiwEqaUt8nfw3cOm1KVA9rz1I9RHnXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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