SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '125629aa7c81c2802f30c39d72199f23b76d39546dbe33890e1d4cb3c58bf3de' 
  AND token = 'TZA+CgPNSaCL0F/mqLk/QUw9ayBO3VetJ6vyfPrgRv4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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